I have read everything I can find about motor mounts for the M-35, and didn't find any posts of someone here replacing them. So, I invite suggestions.
The same part was used/listed for the M-25XP and several other Universal engines, down to the M-12 (which we had on our Pearson 27-2). The weight difference is about 30lbs from M-35 (335lbs, 30 hp, 4cyl) to M-25XP (285lbs, 23 hp, 3 cyl), and M-12 (175lb, 10 hp, 2 cyl), plus transmission. The part has a base with 4" between slots to mount, and a 5/8" stud to tie to the engine bracket. So, the same isolator is on various engines.
Weserbeke part 300974 (now) and aftermarkets with the same dimensions, and appearance are vastly different prices. WB wants $193.90 each. Toad is a little less for the same part. Western Branch Diesel doesn't have any, and again said WB's computers are down so no price/availability info. Cat.Direct has one at $161.80, and is an aftermarket of unknown manufacture. They explained it works on the M-25XP, and are told the bolt pattern is the key. Toad sells one by Bushings, Inc., DF2205-2 for a mere $56.28.
On the other hand, Vetus. They confuse me. Many posts on putting the KSteun75 or 50 on the M-25XP engines. Vetus info puts the weight limit at 165# for the K75, and 220# for the K100, which is too low for the M-25XP and the M-35, unless the limit is per isolator. It appears the hp rating is fine for these engines by their specs. The mounts don't look anything like the OEM, and I understand those who have used them found the 1/16" difference in bolt mount OK. The price is about $70. I have called Vetus US and await a call back to discuss.
Has anyone experience with the M-35 isolators, the Bushings, Inc or the Catalina Direct units? Anyone put the Vetus on their M-35? Am I missing something on the weight limits? I really don't want to do this twice, but don't want to pay 3x the price if I can reasonably avoid it. $56.28 v. 193.90 is the maximum $ difference, per isolator.
Thank you for any insights, again.
Bill
The original isolators on the C30 XP were the DFs. I would expect they are the same used on the 34 engines.
The weights are per isolator- the manufacturer does not know whether the particular application would have 3, 4, or 6 isolators.
The K75 is the common wisdom for the XP, etc. so if the weight is within the range that's the way to go.
The isolators that WB used on B engines are completely different and problematic replacing w/a non-Wb due to the spacing. I haven't found who supplies those isolators to Wb but they're excellent.
Thank you, Ken. I am going to call Vetus again on Monday to see what they say. The K75's at four of them are well within the weight range. The DF's look identical to the Universal ones on there, and to the CD offering. So, that will be my fall back.
Quote from: WBev on September 26, 2021, 08:54:14 AM
Thank you, Ken. I am going to call Vetus again on Monday to see what they say. The K75's at four of them are well within the weight range. The DF's look identical to the Universal ones on there, and to the CD offering. So, that will be my fall back.
What are you anticipating Vetus to say, "No, don't buy our isolators, install the DFs"?
There's plenty info in the archives that say the K75s are the way to go.
Ken, my questions have to do with, given the weight and HP difference of the engines (the consensus here pretty much refers to the lighter and less HP M-25XP), and considering that difference, which of the isolators they recommend between K75, K80 and K100. The 75 v 80 isolators spec very similarly, with the 80 being slightly stiffer (their chart labels it as "hardness"). These two have the same weight max and dimensional specs. I expect the K100 will be too stiff.
This question arises because I read several posts regarding the K50 being too soft for the M-25XP, and recommendations to use the K75. There is a bigger difference between the 50 & 75, but not much between the 75 and the 80. (I have not looked around for any retailers selling the 80, but did not see it on two websites I looked at.)
I may be over-complicating this, but I do not want to do this twice.
Bill : When I finally got the Vetus mounts for my M25XP engine, I found that the K50 were too soft in the REAR mounts. The K50s in the rear allowed the drive shaft to just touch (buzz - a mild tickity tickity) against the packing gland tube when the engine was idling - not when the engine was at higher than idle rpm!! After I changed to the K75s in the rear the engine was perfect. Then (for simplicity) I just recommended the K75s all the way around.
If I had your engine I'd go for all K75s - which I'm sure will be OK.
A few thoughts
Interesting how the 3-cyl M-30 was 425 lbs and the M-35 is 335 lbs. Wait. Huh?
I don't know that the 80s are (readily) available in the US of A. My distributor shows the K75 in stock but K80s not even listed as available. But I might be able to special order.
Will be interesting to hear what Vetus says but here's my take.
On the 35, the K75s are ok. If you want a titch more peace of mind K75s on the front, K80s on the rear.
With the higher Shore Hardness of the K80, you'd get less movement (i.e., Ron's issue w/ the K50s in the rear) but more vibration transferred to the stringers. If that doesn't bother you, with the relatively little difference between them the K80s might provide a titch more service life (like 3 to 5 yrs.)
I'm looking for a new set of engine mounts for my M35B. My mechanic says that the old ones are too soft and worn out. The engine is moving to the side when put in gear, causing metal-to-metal contact between shaft and stuffing box. Note that the B-series mounts are totally different from non-B-series mounts. The Westerbeke service manual shows the part number is 040510:
https://www.westerbeke.com/Product/ISOLATOR/040510
There is some discussion of these M35B mounts on another old thread: https://c34.org/bbs/index.php/topic,5187.msg31839.html#msg31839
Apparently it is difficult to find alternate designs that match the 5" spacing of the lag bolts, and drilling new holes would probably require removing the engine.
The price for genuine Westerbeke replacement is showing up almost everywhere at $279.70 per mount. There is a place in Annapolis that shows it online at $255.98, though I have not verified whether they have them in stock and/or whether their price is obsolete. This will be painful to buy 4!
I cannot find a comparable design on the Vetus website. I have no idea who might make these mounts for Westerbeke. Do you guys have any suggestions?
I've searched on and off for 3-4 years trying to locate those isolators. No joy.
I'll ask my Ex-Westerbeke distributor if he knows the mfgr, but I doubt he does.
I don't see why a shop couldn't weld a thin plate under the K75 or K100 isolators and redrill at 120mm instead of the 100mm.
Quote from: KWKloeber on October 10, 2021, 02:08:29 AM
I've searched on and off for 3-4 years trying to locate those isolators. No joy.
I'll ask my Ex-Westerbeke distributor if he knows the mfgr, but I doubt he does.
I don't see why a shop couldn't weld a thin plate under the K75 or K100 isolators and redrill at 120mm instead of the 100mm.
Thanks, Ken. I'm really reluctant to experiment with custom modifications for something that undergoes so much stress and can cause so much damage if it isn't the right thing.
By coincidence, I have to be in Annapolis tomorrow morning (about 2.5 hours away from home) and could swing by and purchase the four Westerbeke mounts for about $100 less than everyone else is selling them for, so if you can come up a non-Westerbeke source for the exact same thing before that, I'll hold off.
I sent an email but I don't know if they are closed tomorrow for the holiday. I'll post as soon as I hear.
As far as experimenting, I'm not sure which you refer to but at least I wouldn't consider neither Vetus nor welding experimenting. They're both proven and been around and have worked for at least a few months now. Would welding be more or less resilient and long lasting than the rubber that sits between the stringer and the engine?
Westerbeke isolators are absolute, no question, unadulterated raping of the customer when the should be under $100. I'll NEVER buy them!
Quote from: KWKloeber on October 10, 2021, 10:30:31 AM
I sent an email but I don't know if they are closed tomorrow for the holiday. I'll post as soon as I hear.
As far as experimenting, I'm not sure which you refer to but at least I wouldn't consider neither Vetus nor welding experimenting. They're both proven and been around and have worked for at least a few months now. Would welding be more or less resilient and long lasting than the rubber that sits between the stringer and the engine?
Westerbeke isolators are absolute, no question, unadulterated raping of the customer when the should be under $100. I'll NEVER buy them!
Thanks for checking. I had forgotten about the holiday, since no company that I've worked for over the past 35 years has ever observed it. But now that you mention it, the Annapolis Powerboat/Sailboat shows bracket the holiday, and so the place I was going to visit might actually be closed. I'll have to check the exhibitor list. All this means I might just have to delay and eventually do mail order.
As far as the "experimental" nature of this, the below question about flex couplings, which was apparently never answered, highlights that swapping this part out on a B-series engine may not be as simple as expected. Have any of your clients, or anyone else here (or maybe on the C36 forum), ever actually done this proposed Vetus swap-out with the welded plate modification on a M35B, M40B, or M50B? Exactly which model of Vetus isolator was used? Until all of these questions are answered, I'll have to consider this whole thing as "experimental", and not sure I want to be the guinea pig. It is not apparent to me that John Langford or anyone else has actually done this with a non-Westerbeke part.
Quote from: John Langford on August 28, 2009, 10:49:46 AM
Here is information that won't make Canadian Mk II owners very happy. Westerbeke Canada wants $297.29 for each engine mount for the M35B. And I was trying to get used to the American price of $182! (since increased to US $280 as of Oct 2021)
It's a lovely engine but being at the mercy of Westerbeke is painful. There has got to be another mount out there that we can substitute. I went to the site recommended by Roc and it does have a lot of mounts. But sorting out which mount would be a good substitute is a problem.
Ron, did you have a view on the question of whether the Vetus K75 requires that then engine have a flex coupling?
Just update reply #7, my stocking distributor verified that the K80s are not available, except by special order (that currently could take several months to manufacture.)
My recommendation based on additional weight for a 4 cylinder are K100 on the rear and K75 on the front.
Guys : I don't believe that any engine mounts I've seen require a flexible coupling!??!
I've just always had a flex-coupling because I'm lazy and want my engine/drive shaft to stay in alignment!! For a few bucks - why NOT??? :thumb:
A few thoughts
It looks like Bushings has a very wide variety of engine mounts:
https://www.bushingsinc.com/119-2/
Many of them are 5" hole spacing, but they are all for larger, heavier motors. The ones for motors like the M35B are typically 4" hole spacing. I don't know whether they have any customization capabilities, but it would be nice if they could mix&match some parts to come up with a 5" hole spacing with the right hardness of rubber and stud spec. to work with the 352 lb. M35B. I think I'll give them a call and see what capabilities they have to come up with something like a DF-2205-2 with a larger base plate with 5" hole spacing. With their "competition" pricing their parts at $280 each, it would seem that they have a lot of potential profit margin with this design.
Quote from: Breakin Away on October 10, 2021, 06:19:29 PM
It looks like Bushings has a very wide variety of engine mounts:
https://www.bushingsinc.com/119-2/
Many of them are 5" hole spacing, but they are all for larger, heavier motors. The ones for motors like the M35B are typically 4" hole spacing. I don't know whether they have any customization capabilities, but it would be nice if they could mix&match some parts to come up with a 5" hole spacing with the right hardness of rubber and stud spec. to work with the 352 lb. M35B. I think I'll give them a call and see what capabilities they have to come up with something like a DF-2205-2 with a larger base plate with 5" hole spacing. With their "competition" pricing their parts at $280 each, it would seem that they have a lot of potential profit margin with this design.
But then on the other hand...
https://forums.sailboatowners.com/threads/anyone-tried-these-motor-mounts.140689/#post-916087
Still researching what to do.
There's NO comparison btwn Vetus and DF, hands down they are in different leagues. I'd never replace my DF's on my 25 with the same. No reason to when the cost is essentially the same.
Verus has 5" also, but just for monster HP engines.
Are you aware that a proper weld is stronger than the metal welded? The metal next to it will fail before a weld does.
One benefit is that the slot could be custom-sized for necessary lateral adjustment. Another is that the thickness of the plate could be set tsp the engine mount sits at the lower third of the isolator stud.
Here's, unfortunately, the reply
"Believe that these were Westerbeke' s own design & you can only get them from Westerbeke. Thx, JD"
Breaking : How many hours do you have on that engine? that you now need to change out mounts because they are "Too Soft" ?? :shock:
A question
808 hours
Quote from: Breakin Away on October 11, 2021, 02:42:44 PM
808 hours
Wait a minute -- Bad after 800 hrs and you want to replace them with the same?
I think I am going to do some additional inspection and measurements before buying anything. When placed into gear, the torque of the motor pushes the shaft up (slightly) and to port (mostly), causing shaft-to-nut contact
at about 2 o'clock when looking aft toward the nut. I want to measure how far up the adjustment nuts currently are on the studs, since lateral movement would be reduced by 75% if I can raise the mounts enough to for the mounting flange to rest halfway lower on the studs. It may be that I can solve this problem by raising up the current mounts with spacers. But first I need to measure, and I will not be able to get to the boat until at least next weekend.
A few additional facts:
I originally discovered this issue when I put a white tissue under the stuffing box to help detect dripping water, and found fine bronze particles. At that time I did not know how long the problem had been happening. I've been putting down the tissues periodically for awhile, but this time I happened to have some sunlight hit the tissue at just the right angle to see some shiny specs, which led me to get out a magnifying glass and take a closer look.
Alignment appears to be fine when the motor is in neutral or not running. The packing nut is well centered on the shaft in this state, with an even 0.01" gap. The issue only appears when in forward, and gets worse at higher RPM (due to higher torque on the mounts).
The stuffing box was replaced in early 2019, along with original bronze shaft (Aquamet G22 upgrade), strut, prop, and coupler. I just inspected the old stuffing box and shaft that were removed at the time, and can clearly see wear patterns that suggest that this issue had been present (and undetected) for quite awhile before 2019. I purchased the boat in 2016, and not sure the surveyor would have detected this.
There are no vibrations in the system, except for idling below 900 RPM (according to the console tach). I have it on my list to recheck the idle RPMs using a strobe on the motor - it might actually be below the M35B spec of 800-1000 (Service Bulletin #236). Getting up to 950-1000 immediately eliminates the vibration. The <900 RPM vibration happens in neutral, so it appears to be unrelated to running gear or alignment.
I appreciate all your suggestions. However, the boat is 20 years old, and synthetic rubber can dry out and/or lose resiliency over time, even with low engine hours (oxidation in air and evaporation of plasticizers). Based on what I've read, it's not uncommon to replace mounts after less than 20 years. However, I understand that it is not a sure thing that my mounts are bad, or that new ones would be any better, which is why I am going to do some stud measurements and, if the motor is mounted too high on the studs, consider spacers under the current mounts as a first attempt before shelling out money for new mounts and/or custom welding.
[edited]
Well that's a ton more info.
Good info. It does sound like more "study" is a wise path to follow.
Could you first observe the isolators/engine mount interaction and whatnot else while under different torques, maybe video it? To nail down precisely what's happening?
Then IIWMB I think before I did more (depending on what I saw and where all the mounts sit on their isolator studs) my next step might be to remove one (or more) and determine their condition.
Note that Wbeke uses the same isolators on the XPB and on the 35B [ and 40B.] Food for thought.
Breaking : The first thing that I'd try is to replace the fwd port mount (incase oil from changing the filter may have gotten on the "rubber") and see if that helped. Do you know if any of the "Prestone" internal coolant might have dripped on any of the mounts (while changing to new hoses?).
A few thoughts
You guys suggested that 808 hours was a short lifetime for engine mounts. I talked to a mechanic today who said that Westerbeke says to replace them every 500 hours. I've been unable to find this in my manual. He also said that lateral motion should be impossible unless the studs are broken. Comments?
Quote from: Ron Hill on October 12, 2021, 01:17:41 PM
Breaking : The first thing that I'd try is to replace the fwd port mount (incase oil from changing the filter may have gotten on the "rubber") and see if that helped. Do you know if any of the "Prestone" internal coolant might have dripped on any of the mounts (while changing to new hoses?).
A few thoughts
In the time I've owned the boat, there has never been a drip of oil or Zerex on any of the mounts. It is not difficult to ensure this never happens. I'm not sure that replacing only one mount would be a good use of time, since you need to redo the whole alignment with each change.
PS If you are looking at sizing other than Wb isolators the rule of thumb is 60-70% of the weight sizes the rear ones, 30-40% the front.
I remember some forum post where a westerbeke owner made an adapter plate for 4" CushyFloats - not welded but bolted to the plate and plate drilled at 5". Interesting approach, but not how I would go.
The Wb isolators "encapsulate" the rubber -- so long as the rubber is "totally intact" (theoretically) one can't move sideways. But if the rubber is compromised, not competent, then (theoretically) they can move sideways.
You only know you can show. Why not ask him where he got that info about the hours - page and line number.
This is what I am saying -- you need to get your head down in there and nail down precisely what's going on.
I never automatically trust someone else who has a vested interest in separating me from my cash when that person knows I am ignorant about what s/he's telling me.
Quote from: KWKloeber on October 12, 2021, 05:23:13 PM
PS If you are looking at sizing other than Wb isolators the rule of thumb is 60-70% of the weight sizes the rear ones, 30-40% the front.
Are these percentages for each isolator (65%+65%+35%+35%=200% total) or for the sum of front/rear (65%+35%=100% total)?
As you might know, Westerbeke specs the same for all 4 corners. P/N 040510 is 75-125 lb. With a 352 lb engine, that's 21-35% of the engine weight for each mount (or 84-140% total), so that's a lot less support than your first suggestion.
I'm calling people about potential haulout facilities for this fall (might change from my current yard), and I'm working in a discussion about motor mounts as part of that discussion. The guy I spoke to today took over ownership of the marina from his parents and has been doing engine repairs for his whole life. He seemed very knowledgeable, rattling off all sorts of facts from memory (including key differences between C34MkI and C34MkII, and differences between Wb B-series and prior motors). His statement of 500 hour replacement interval was from his memory. As you can probably tell, this guy also seemed a little arrogant and snarky (in other words, too much like me :razz: ), so I did become a little suspicious of him. Among his "hot button" issues is user forums, which he insists I am wasting my time with. However, he also rattled off some of my neighbors as regular customers of his service department, and I'll check with them about whether this guy is as good as he seems to think he is. While I am considering DIY for this job, I'm also considering hiring it out since I may get in over my head and need to buy an awful lot of tools (and spend dozens of hours making trips back and forth to my boat in accumulating the needed tools).
The 35B engine is probably 370 - 375 wet weight.
375 *(40%) / 2 = 75 static lbs. ea. front
375 *(60%) / 2 = 113 static lbs. ea. rear
Understand this is rule of :thumb: - you would need to know the center of gravity of the M35B/tranny but it's close (give or take.)
I know there's a way to make an adapter plate, even w/o welding.
QuoteI talked to a mechanic today who said that Westerbeke says to replace them every 500 hours.
Using that Shamrock would be on it's 3ed set. Something to consider. Estimating cars, 500 hours @ 50mph would be 25,000 miles. Don't know of any cars that call for motor mount replacement intervals. Not saying that your motor mounts don't need changing, just think that would be very short life unless some harm was done to them or they were defective.
Jim
Quote from: KWKloeber on October 12, 2021, 09:36:58 PM
The 35B engine is probably 370 - 375 wet weight.
375 *(40%) / 2 = 75 static lbs. ea. front
375 *(60%) / 2 = 113 static lbs. ea. rear
Understand this is rule of :thumb: - you would need to know the center of gravity of the M35B/tranny but it's close (give or take.)
I know there's a way to make an adapter plate, even w/o welding.
If I go with Westerbeke, should I do the rear ones with #040511 (125-220 lb)? The mechanic seemed to want to go stiffer.
PS: When staying crap I'm talking parts direct from the factory in some instances. Literally at least 25% were 'less than a seamless experience.' Like Wb shipping a clearly defective part, refusing to believe it, even with pictures, having to pay to ship parts back, getting another defective of the same part, and finally having to hunt down a distributor that had a good one and beg him to ship outside his district. There was no QC on incoming parts that were made who knows where, and all they did was pick a part out of a bin and ship it w/o looking at it, even after being notified the parts were defective. This happened too many times. And customers I've told to just order direct have had similar issues.
Quote from: Breakin Away on October 13, 2021, 12:31:13 PM
Quote
The 35B engine is probably 370 - 375 wet weight.
375 *(40%) / 2 = 75 static lbs. ea. front
375 *(60%) / 2 = 113 static lbs. ea. rear
Understand this is rule of :thumb: - you would need to know the center of gravity of the M35B/tranny but it's close (give or take.)
If I go with Westerbeke, should I do the rear ones with #040511 (125-220 lb)? The mechanic seemed to want to go stiffer.
First, I don't typically recommend a Wb product if there's a better or even equal alternative. I've seen the quality (or lack thereof) many times. I could show you pictures of their (not Kubota) nightmares. I was a Wb dealer and I've seen parts that were crap, so after my stocking distributor (who would sell me anything that I wanted for a Wb engine) gave up repping Wb, I'd have to give a customer an inferior part over a better non-Wb part, so I won't do that and wouldn't sign a dealer agreement w/ Wb.
2nd, understand the above are static loads. You need to know the rating of the Wb isolators for dynamic loading?
Guys : What a blast!!! - when you think that the Atomic 4 was bolted directedly to the stringers - no mounts!!
A thought
Quote from: KWKloeber on October 13, 2021, 01:55:44 PM
First, I don't typically recommend a Wb product if there's a better or even equal alternative. I've seen the quality (or lack thereof) many times. I could show you pictures of their (not Kubota) nightmares. I was a Wb dealer and I've seen parts that were crap, so after my stocking distributor (who would sell me anything that I wanted for a Wb engine) gave up repping Wb, I'd have to give a customer an inferior part over a better non-Wb part, so I won't do that and wouldn't sign a dealer agreement w/ Wb.
I get it, Ken. You don't like Westerbeke. We went through this when I had a raw water pump problem, and everyone was all gung ho about using a ground-down Oberdorfer. This time, just as then, I will consult multiple sources, and go with the advice that seems most technically feasible. Like before, it will be impossible for me to choose a path that all the conflicting parties are suggesting. In that case I had Depco rebuild my Sherwood pump because Depco showed data that the Oberdorfer was sufficient pumping capacity for the M25 motors, but not sufficient capacity for the M35B. Had I gone with the crowd who sang the praises of Oberdorfer with their smaller engines I might have been happy for awhile, but I'd likely be "on the edge" in mid-summer when Chesapeake Bay water temperatures climb into the mid-80s. It wasn't right for me.
Now, as then, I am looking for advice specifically for my M35B, which has different mounts from the non-B motors. Why did Westerbeke make this change when it would have been so easy to keep the same mounts as before? I am open to considering your suggestion, but once again I want advice specific to my M35B. First, in order to avoid being a "guinea pig", I'd like to hear from anyone here who has actually used the modified Vetus mounts and will attest that they are indeed superior to Westerbeke's junk. Rod said that he forks over the extra money for Westerbeke mounts, and I have huge respect for him, so I need some pretty solid evidence to get me to go against his advice. Second, since you're in the industry and presumably have a lot of contacts with machine shops (while I have exactly zero such contacts), I'd be thrilled if you could provide a quote for fully assembled drop-in replacement that is guaranteed to fit my hole pattern and engine flange. You say that these mounts should cost under $100, so let me see evidence of that and I'll consider buying it from you. I'd be a fool to pass up a superior $100 product (actually 4 of them) and go with four inferior $280 products. But right now there is no such product that I can see - only advice that I should spend a bunch of time to go find a my own machine shop to modify the mounts. I feel like I'm being sent out on this by myself with no clear precedent from someone else who says they have done it and been happy with the result.
Quote from: KWKloeber on October 13, 2021, 01:55:44 PM
2nd, understand the above are static loads. You need to know the rating of the Wb isolators for dynamic loading?
You got me on two counts. 1) Westerbeke doesn't appear to state the dynamic load limit for their mounts, and 2) I don't know what dynamic loads the M35B puts out when it's running. But I can't find dynamic loads from Vetus for their mounts either. So if someone can point me in the right direction for this information, I'll be happy to take it into account.
Hi Breakin,
I'm in exactly the same position as you. I need new mounts for my M35B, I'm not an engineer and I don't know any skilled machinists. So I have no option other than to purchase the Wb variety which, here in the UK, cost $382 each and take 8 weeks to arrive. :?
QuoteIf I go with Westerbeke, should I do the rear ones with #040511 (125-220 lb)? The mechanic seemed to want to go stiffer.
My 2 cents, I'm very happy with the smooth low vibration on Shamrock. I would be reluctant to change. Even though our boats are close in hull numbers yours may be quite different.
Jim
>>> You got me on two counts.<<<
No one is trying to "get you" on anything, just providing info that you might not be aware of, or maybe the mechanic is not aware of regarding different isolators.
>>>> Depco showed data that the Oberdorfer was sufficient pumping capacity for the M25 motors, but not sufficient capacity for the M35B.<<<<
I'd be interested in seeing that data, maybe post it on the wiki (if I can ever get access.)
Not to take this subject off topic, pls email it?
Quote from: Breakin Away on October 13, 2021, 08:50:18 PM
................................
In that case I had Depco rebuild my Sherwood pump because Depco showed data that the Oberdorfer was sufficient pumping capacity for the M25 motors, but not sufficient capacity for the M35B. Had I gone with the crowd who sang the praises of Oberdorfer with their smaller engines I might have been happy for awhile, but I'd likely be "on the edge" in mid-summer when Chesapeake Bay water temperatures climb into the mid-80s. It wasn't right for me.
.........................................
I think your analytic approach has great merit.
I, too, would be interested in that info. Just a note that our wiki has an Oberdorfer modified to fit their M35; this was before Oberdorfer wised up and modified the base to fit both engines. As well as a few C36s I am aware of from the C36 site. I have not heard of any complaints, certainly not the one you are projecting as a possibility. I don't recall if any were in Florida or similar year round warm water. That, too, would be interesting to know.
Quote from: Breakin Away on October 13, 2021, 08:50:18 PM
I get it, Ken. You don't like Westerbeke.
Had I gone with the crowd who sang the praises of Oberdorfer with their smaller engines I might have been happy for awhile, but I'd likely be "on the edge" in mid-summer when Chesapeake Bay water temperatures climb into the mid-80s
Why did Westerbeke make this change when it would have been so easy to keep the same mounts as before?
attest that they are indeed superior to Westerbeke's junk.
Breakin,
You're embellishing upon my words and that's not at all helpful.
I NEVER said Wb isolators are junk.It's not about liking Wb -- You asked for a recommendation on a Wb part -- saying I can't make a recommendation w/o explaining why wouldn't help much. I have nothing good (or bad, except cost) to say about them BUT based on my experience with other Wb parts and how it cut some corners on the B engines I'm not recommending a Wb part unless I personally know its quality.
I told you what I would use IIWMB. YBYC.
You asked for ideas about making your 5" c-c work. I made suggestions - I'm not interested in manufacturing parts for your boat. If you don't like suggestions, instead of arguing w/ them why not just say, "TY", and ignore them? If you make an incorrect statement or assumption about a suggestion -- sure, I will try to correct it so you have good info, but I don't care what you use. It's YBYC not MBMC and I doubt anyone has any upside whatsoever in making you a guinea pig. If you don't want to "invest" the time to make the Vetus work w/ your 5" c-c, then why not take the easy route and buy the Wb mounts.
I did go to the effort to lay out the mounts to see if an adapter could be made and I believe it could. If you are not interested in contacting a machine shop (there's a good one in MD) then buy the Wb mounts (except I hear you saying that your mechanic doesn't think they are heavy enough?)
As to why....
Wb might change from a DF mount (that you can replace for $60 or so) in favor of proprietary ones that ONLY Wb sells at 450% more? Really? Think about it. Why does Wb install a pump that IT OWNS that's available ONLY as a Wb PART for 300% what it's worth? Really? Think about it.
If Wb isolators are superior how come there's NO PLACE that we can find (so far, and I have searched not for a couple weeks but for 3-4 years) where they are used elsewhere? Who KNOWS where they are manufactured.
How many on here have installed Vetus and had a problem? Vetus is used worldwide with no issues I have heard.
I respect Rod and have not seen a comparison of Vetus vs Wb, or Rod saying that he chooses to replace Vetus with Wb mounts (if he had, I missed it.)
He replaced his Wb mounts because he also has 5" c-c mounting holes on his Westeble engine and I imagine he also didn't want to pull it. You seem convinced about his experiences, yet are searching hard for reasons not to follow his recommendation. If they are THE mount to use then cost isn't an issue.
As to the Ob pump....
Please send the Depco data. It's not my experience w/ the Ob pump on the 35 or 35B. Randy in LA runs an Ob pump. Mick runs an Ob pump. I do however regularly recommend that the barbs and hose changed to 3/4" to get max flow to the intake side but mainly because there are good (proper) 3/4" barbs available but not 5/8" ones.
I know of no data available re: minimum seawater flow for the M35B -- maybe Depco has but I haven't seen it and the (now retired) Manager of the Marine division communicated regularly. When he had issues on a Universal engine he'd call me about it -- Universal Oshkosh used 8 (EIGHT) different pumps and he didn't know the history. In fact he even had me call HIS customer to get specifics and then him what to sell.
Quote from: KWKloeber on October 15, 2021, 01:24:22 PM
...............................
...............................
As to the Ob pump....
Please send the Depco data. It's not my experience w/ the Ob pump on the 35 or 35B. Randy in LA runs an Ob pump. Mick runs an Ob pump. I do however regularly recommend that the barbs and hose changed to 3/4" to get max flow to the intake side but mainly because there are good (proper) 3/4" barbs available but not 5/8" ones.
I know of no data available re: minimum seawater flow for the M35B -- maybe Depco has but I haven't seen it and the (now retired) Manager of the Marine division communicated regularly.
........................................
........................................
As I noted earlier, I, too, would be very interested in this flow part of your discussion.
FWIW, my M25 already had an Oberdorfer on it. When I replaced it soon after my purchase of my boat in 1998, and when I upgraded to a 3 inch HX, I noticed it had 1/2" elbows on it, going to a 5/8" inlet at the HX!!! Someone had somehow "expanded" the 1/2" hose to fit the 5/8" barb on the old HX!!!
I have no idea who did it, and I'm not going to bash anybody. Could have been the factory, could have been a workman the PO hired, could have been the PO, or just gremlins. I'm glad I found it and enlarged the elbow and hose to the HX to 5/8". IIRC, the inlet hose from the seacock was already 5/8".
Quote from: Stu Jackson
before Oberdorfer wised up and modified the base to fit both engines.
I think you meant to type "before Oberdorfer ... stole the design ... to fit both engines." :shock: :shock: :shock:
If you recall I was the first to machine a round-base pump for the B engines (below.)
https://c34.org/bbs/index.php/topic,8148.msg56869.html#msg56869
Beta tested it on a friend's XPB. And :thumb:
Showed it to Depco, contacted Ob about buying unmachined pump bodies (to machine both round and bolt-on pumps) and (what a coincidence) six months later Oberdorfer (before selling the company) "announced" the 908 pump. :devil :twisted:
Guys : I have said it MANY MANY times. Just look at the larger size of the pump cavity, look at the increased number of impeller vanes and look at the amount of water coming out of the exhaust. The Sherwood pumps MORE water.
The real question is "does the Obodoffer pump ENOUGH water to satisfy the cooling requirement of the M35BC engine??? Westerbeke (the makers of the engine) doesn't think so!!!
So argue between yourselves !! :cry4`
A few thoughts
Quote from: Ron Hill on October 15, 2021, 04:35:47 PM
Guys : I have said it MANY MANY times. Just look at the larger size of the pump cavity, look at the increased number of impeller vanes and look at the amount of water coming out of the exhaust. The Sherwood pumps MORE water.
The real question is "does the Obodoffer pump ENOUGH water to satisfy the cooling requirement of the M35BC engine??? Westerbeke (the makers of the engine) doesn't think so!!!
So argue between yourselves !! :cry4`
A few thoughts
Naw, Ron, it's more fun arguing with you. :shock:
Look, all I've said is that many skippers have replaced their Sherwood pumps with Oberdorfers on their own M35 engines and the engines keep working.
What's so hard to understand?
We all know, thanks actually to Ken who has documented this about the many different components in the Sherwoods, the shortcomings of those pumps.
Where in the world did you "officially" "get" this "
...Westerbeke (the makers of the engine) doesn't think so..."?
I'm still waiting for the Depco "official" "data", too.
It seems to me that the pump volume specs shouldnt be that hard to come by from the mfg. The larger number of vanes wouldnt make a difference in volume but might make the flow more even. It is actually the unoccupied volume of the impeller chamber (impeller chamber volume minus physical volume of the impeller) that would make the most difference in the water flow rate. Based on that assumption, I suspect these two pumps wouldn't produce markedly different flow rates.
It's not the pumping rate that is the question, it's how much flow does the engine need??
Yes the Sherwood (reportedly) pumps more (I haven't measured it and I question manufacturer's flow specs) BUT what does the engine require and is the additional volume simply "excess." (Not that excess is a bad thing.)
Quote from: KWKloeber on October 15, 2021, 06:48:07 PM
It's not the pumping rate that is the question, it's how much flow does the engine need??
Yes the Sherwood (reportedly) pumps more (I haven't measured it and I question manufacturer's flow specs) BUT what does the engine require and is the additional volume simply "excess." (Not that excess is a bad thing.)
That's a very good explanation of the engineering analysis approach and is a perfect example of the way to look at it.
I doubt, from what I've posted earlier, that the flow differences are so much that the differences (reportedly true) would be apparent or meaningful
to the engine, especially if the Oberdorfer meets the minimum flow rate for the engine and, of course, the associated HX. It appears from the application of these pumps to that engine that they do.
I mention HXs to remind many who may not know that many of us were successful in keeping our M25 engines within specs by upping to a 3 inch HX from the OEM 2 inch model. Just like Universal did with the M25XP and the 2 additional engine HP was not why they upped the size of the HX. The conclusion was always that the 2 inch HX was marginal for the engine load; it worked just fine when the HX was brand new, but age, use, salt deposits on inlet ports all contribute to reduced effectiveness and lack of heat exchange at WOT, which was the original M25 issue.
I've been traveling and unable to respond. I'll try to clarify a few points:
I probably shouldn't have distracted this discussion by bringing up the "pump wars". But there are parallels here. I've spent my entire career in product development R&D, and I refuse to believe that companies just go and intentionally change their components to more expensive and inferior replacements. Adding more SKUs to the parts list is costly, and qualifying new suppliers is excruciating. So whether it's changing to a Sherwood raw water pump for the M35B or changing to totally different engine mounts for the B-series, these changes were certainly made for a reason, and I refuse to accept that the changes were done solely to produce an inferior, overpriced product.
I have searched all over for acceptable motor mounts and called multiple suppliers with no luck, so I'll probably just buy the Westerbeke mounts. I am not willing to custom modify something. If the modification doesn't work for some reason, I'll have ZERO support. And my motor runs smoothly with the current mounts, just like Jim Hardesty noted. I just need to go have another look to verify the sideways motion that the mechanic noted. I'll also double check the lock nuts on the studs to make sure nothing has loosened up. It's also possible the mounts were damaged in the underwater strike 2.5 years ago that led to the prop, strut, and shaft needing replacement. The insurance surveyor was outstanding, but maybe he missed some damage to the mounts.
Quote from: KWKloeber on October 15, 2021, 01:24:22 PM
You're embellishing upon my words and that's not at all helpful.
I NEVER said Wb isolators are junk.
Junk was my word. I apologize for my sloppiness. However, you did use the word "crap" a couple of times, and said their defect rate is literally at least 25%. So while you're not making a direct accusation about this particular component, you are making an inference about Westerbeke's overall quality. And, more importantly, I still have heard from zero people who have successfully used Vetus mounts on an M35B, so I consider a custom mod of a Vetus mount to be more risk than I want to take. The project could consume my entire winter.
I've heard enough complaints about Westerbeke to know that they probably have some serious customer satisfaction issues. So I can't just ignore your concerns. Fortunately, I have not been personally burned on this yet, and Hansen Marine once backed me up on a Westerbeke issue that was partially my fault. That earns them another shot.
I've gone through my notes about the pump replacement, and I cannot find any data directly from Depco. My notes show that on 5/31/2018 Depco told me that the Sherwood pump puts out 25% more water at a given RPM, and that they do not recommend the Oberdorfer N202 for any engines over 30 horsepower. At some point I saw some graphical data, but I don't have it in my files. I probably saw it online, and not sure where.
Quote from: KWKloeber on October 15, 2021, 06:48:07 PM
It's not the pumping rate that is the question, it's how much flow does the engine need??
The M35B is 67% more powerful than the original M25, and the amount of heat that must be removed from the system is exactly proportional to the horsepower. I believe the M35B also idles and cruises at about 20-30%
lower RPM) than the M25, so it is easy to understand that the M35B requires a larger pump cavity for more water throughput. At some point I held the replacement impellers for both pumps in my hands side-by-side, and it's very clear that the Sherwood has a significantly larger pump cavity than the Oberdorfer. Maybe you can get away with the smaller pump on an M35B in 45F water on the west coast or Great Lakes, but in the Chesapeake Bay in August you might bump up against the Oberdorfer's more limited heat removal capacity. Maybe with a brand new heat exchanger it will work, but that heat exchanger won't be new forever. Maybe it will work fine in calm water, but I'd hate to have to motor into a 25 knot wind and punching through 3-4' chop and find out that the motor overheats under the strain.
Quote from: Stu Jackson on October 14, 2021, 01:56:13 PM...Just a note that our wiki has an Oberdorfer modified to fit their M35; this was before Oberdorfer wised up and modified the base to fit both engines.
Just because the Ob flange fits the M35B does not mean that it has sufficient pumping capacity to remove heat under stress conditions.
Quote from: Stu Jackson on October 14, 2021, 01:56:13 PMI have not heard of any complaints, certainly not the one you are projecting as a possibility.
Back in 2015 Mick Laver went through hell with his Oberdorfer experiment on his M35B, with problems exactly like I'm describing. He returned it to Depco for the Sherwood. Then he went through it again, repeating the same experiment with Ken. You guys seem to forget this. And Ron Hill also tries to remind you of this issue.
Quote from: Stu Jackson on October 11, 2015, 09:28:10 PM...However, I have to share with you the fact that this "flow rate" stuff has been around for years and makes little sense.
When dealing with heat removal capacity issues, "flow rate stuff" is the most critical design parameter. If a motor is 67% more powerful, it needs more water. The fact that the Oberdorfer N202 works OK on some M35B motors under certain conditions basically means that it's over-designed for the smaller motors, but for motors over 30 hp it is marginal, working adequately under ideal conditions but potentially not up to the task under high stress conditions.
And while it is true that a brand new, unfouled heat exchanger may overcome some deficiencies in pump design, heat exchangers don't always stay that way. In fact, there is a scenario where an infinitely sized heat exchanger cannot overcome an inadequately sized pump. Just do a heat balance around the motor, and you can see that there could be a situation where even with perfect heat transfer from the raw water side to the freshwater side (infinite heat exchanger capacity), the raw water heats up to 212F (because there isn't enough flowrate), and you're injecting steam into the exhaust elbow. The only way for the motor to expel its heat is through the water, so without enough water even a better heat exchanger may not help you.
This all makes perfect sense to me. As you get to higher power and heavier engines, you need a bigger pump - and bigger engine mounts.
I believe that you're stating some conclusions as fact, based on incorrect or at least incomplete ?assumptions? (or maybe bad info.)
1. You're concluding that you would have a problem w/ an Ob.
- You want hard data that a Vetus will work on a 35B, yet it's only an opinion that an Ob will be an issue on the chessie, not based on (hard data of) what flow a 35 needs. Is it 100% of the Ob flow or 50% of the Ob flow? Yes an extra cylinder puts out more heat, that's a given.
- You must have missed Mick's follow-up. With the problem resolved he moved back to the better-built bronze Ob pump.
- You forgot that Randy in the Gulf has an Ob w/ no issue.
- You cited no data supporting that the Ob "works on some" "under certain conditions" and is "marginal" for over 30 HP. Unsubstantiated conclusions -- where's the beef?
- Your comparison picks and chooses data. The Ob is just fine on the XPB, and the 35B is 35% greater HP (not 67% as the M25.) Yes, HP is higher but let's use relevant data for comparisons. Note that the M25 originally had the 2" Hx, and the Sw did not fix that overheating issue.
2. Flow comparisons:
- I believe that the 25% number that's thrown all about the internet is bogus, and was originally supplied by Westerbeke (like they have no vested interest in exaggerating it) and has been perpetuated. See the flow ratings below. NOTE: The Sw curves show no relation to head so the rating is at zero (a head game :cry4` that pump manufacturers play on us.) The Ob is about 9.4 gpm, the Sw about 11 gpm. That's 17% more flow, not 25%.
3. That Wb "moved" to the Sw pump.
- You're unfamiliar with the history of pumps on Oshkosh and Wb engines. Wb did not "move" to the Sw on the B engines, it has ALWAYS installed IT's OWN pump -- which Sherwood does not own, Wb owns it, and Sw cannot sell it except as a Wb part (and at Wb's price.)
I do hope that the damage caused your mount problem - at least then you'll be somewhat assured that replacing them won't lead to a premature failure. But it's interesting that the mechanic feels they are not the proper rating. Just based on published data I'd agree the rears should be heavier.
Why not get Vetus' take/recommendation on that engine (regardless if you don't use them)?
BTW, Hansen is not the Wb dealer/distributor for the chessie area, so I am unsure how they backed up anything but otherwise must never sell in that region. Regardless, the "crap" was referring to known defective parts and the 25% was a percentage of identical parts (one in four were bad) -- just to be clear -- in NO WAY am I implying that Wb has a 25% overall failure rate. Words are very loose and so are the inferences drawn. Just as you feel about the Vetus, I have no hard info whether the isolators are "just fine" (or not.)
A few more points on loose facts leading to loose conclusions.
There's no data citec to support the statement (conclusion) that the pump flow is "marginal" for the 35B.
The water flow is not "THE most critical design parameter" it's ONE parameter. Just as a scenario can be conjured up where an infinite Hx with too little flow is a fail, also a scenario with infinite water flow and too small a Hx can be conjured up and also be a fail. Picking' n choosin' to support a pre determined conclusion.
The cruise RPM on the XPB and 35B are identical, and so the flow isn't reduced on the larger engine.
And, yes the idle is 800-1000 compared to 1000 - 1200, but it's irrelevant.
At idle the coolant generally doesn't get hot enough to open the TStat. In other words on the original early M25s (that had the water heater in line with the Hx) they couldn't make hot potable water at idle, only under load. Possibly the 35 will open the TStat but still it's not the significant/critical condition.
I'll say a few words about my decision logic. I come from a Six Sigma engineering background. For long-life durable items, my default position ("null hypothesis") is always going to be to follow the manufacturer's recommendation unless 1) the recommended part is discontinued or manufacturer out of business, forcing me to another alternative or 2) I have compelling evidence (95% certainty) that an alternative is better (superior performance, or equal performance at significantly lower cost). That does not always have to be "hard data". It can be user experience (which still appears to be zero in the case of using modified Vetus mounts on an M35B), controlled experiments (where Mick Laver's experience suggests that the Oberdorfer may be insufficient in certain non-ideal conditions), or solid engineering calculations backed by well-known engineering theory (a 35 hp M35B generates 67% more heat than the original 21 hp M25). The threshold of 95% certainty is a high bar, but IMO it is appropriate for critical components like engine mounts and cooling pumps. Plus MBMC.
Regarding engineering considerations, recognize that a heat exchanger does not provide cooling - it just transfers heat between the heat source (engine horsepower) and the heat sink (raw water). The water comes in at sea temperature (which can be very different in different places), and goes out significantly warmer, and hopefully below boiling temperature. The heat exchanger merely transfers the engine's heat from the freshwater side to the raw water. So with a smaller pump and a bigger/better heat exchanger, your thermostat may say the engine temperature is fine, but the raw water that then goes into the exhaust elbow will always be warmer. This is an irrefutable fact, since the only place for the heat to go is into the raw water. And this hotter water can lead to other issues, like precipitation of more minerals in the exhaust elbow (leading to clogging), faster degradation of rubber hoses due to higher temperatures, greater thermal expansion/contraction of muffler, muffler mounts, and other components, etc. Yes, this is speculative and not a "conclusion", but it is irrefutable that lower water flow with higher horsepower (energy) will lead to hotter water.
I still am not ready to buy into your anti-Westerbeke bias, where every recommendation they make is based on some sinister motive of self interest, and a failure of one out of four parts turns into a conclusion of "literally at least 25%". Maybe someday I'll get burned and come around to your way of thinking.
I acknowledge that there's an element of self-interest in everyone's recommendations, including yours and Westerbeke's. That's human nature, and not sinister. Interestingly, Depco might be the least biased of anyone, since they'll sell or refurbish either pump. (They rebuilt my Sherwood for only $87.99 in 2018, since it was only one seal that was worn out.) And Depco says the flowrate of the Oberdorfer is insufficient for any motors over 30 hp. Somewhere inside Westerbeke/Universal, there is/was an engineer who did the calculations and testing that determined that the Sherwood pump was the best choice for the M35B/M40B/M50B motors. They probably tested under some abuse conditions, and allowed for reasonable safety margins in making an engineering decision, and took into account the experience and feedback of their customer base. This is purely speculative on my part, but that's how companies that have been around awhile generally work. I'll trust the judgment of that hypothetical engineer until I have compelling evidence that he was wrong. And I have yet to see any hard evidence that Depco's "upper limit" for the Ob pump of 30 hp is unreasonable.
Thanks for posting the chart. I'm not sure why you were asking me to post it if you had that already. Your arrows make it clear that you are not considering the possibility that the larger motors turn at a little slower RPM, which might get it closer to 25% difference. But regardless, every pump will have a limit for how much energy it can remove, and I choose to follow the 30 hp recommended limit of the Ob pump.
Speaking of incorrect assumptions, you seem to think that I live on my boat and that Hansen is violating their Westerbeke agreement. I have no reliable way to receive shipments at my boat, so parts are shipped to my home in Pennsylvania, which is why I am in Hansen's territory.
Good thing the discussion is about cooling, because this conversation is getting hot. :rolling
Guys : Kens' statement -"It's not the pumping rate that is the question, it's how much flow does the engine need??
Yes the Sherwood (reportedly) pumps more (I haven't measured it and I question manufacturer's flow specs) BUT what does the engine require and is the additional volume simply "excess." (Not that excess is a bad thing.)"
Water temperature enters the equation somewhere? and "excess water" just might be just where?? The raw water temperature greatly varies between the Bahamas and norther Maine!!
The Sherwood pump (I found) is a bit more difficult to rebuild and the "C" clip that holds the compression in place was made of bronze!! I found that salt/brackish raw water slowly ate away at the bronze "C" clip just like - Jabsco found out with their bronze "C" at the bottom of their head pump.
I change that clip to SS and had eliminated that problem!! I passed that info back to DEPCO, but don't know if they use it or not?
A few thoughts
Here are some engineering calculations that will go to Ron's questions about "excess" and impact of seawater temperature. There are some assumptions here, but I think they're reasonable. Here are the equations:
• Select a cruising speed of 2500 RPM. I selected this value so we don't have to interpolate Ken's pump performance curves. You could pick 2200 RPM or some other value, but you'd get essentially the same result because both heat generation and pump flowrate would go down roughly in proportion.
• The Westerbeke power curve shows that at 2500 RPM the M35B delivers 31 hp (mechanical) = 79,000 BTU/hr mechanical energy output (see attachment)
The diesel power cycle delivers about 30-40% thermal efficiency (higher than Otto cycle, but obviously lower than Carnot cycle). I'll use the more optimistic value of 40%:
• Heat generated = 79,000 / 40% = 198,000 BTU/hour
• Assume water comes in at 90°F (mid-summer in mid-Atlantic) and exits at 120°F (can't be much higher than this because there will be insufficient ΔT across the HX to keep the antifreeze at 160°F): Net ΔT= 120-90 = 30°F
• Heat capacity of seawater = 4.0 J/g°F = 0.95 BTU/lb-°F (slightly lower than pure water. Note that the BTU was originally defined as a value of 1.000 for pure water)
• Density of seawater = 8.7 lb/gal
• Required seawater flowrate = 198,000 BTU/hr ÷ [(0.95 BTU/lb-°F)*(30°F)*(8.7 lb/gal)] = 800 gal/hr = 13.3 gal/min
If you look at Ken's pump performance curves, you will see that it is plausible that the Oberdorfer might not keep up in warm climates, and the Sherwood pump does a little better because of its larger cavity size. This calculation assumes that all heat escapes in the seawater. There is also some heat that escapes in hot exhaust gas, so my estimate is admittedly conservative. But you can't just assume that the Oberdorfer will work with everyone's M35B in every situation just because it works great with a smaller motor or with someone's M35B under more ideal circumstances.
[EDIT: This is a simplified example that makes an assumption about the heat exchanger (exit temperature of 120°F). A full model would include data on the heat exchanger's shell-and-tube design, including the surface area of the tubes, their heat transfer coefficients in the new and fouled states, number of passes (2-pass, 3-pass, 4-pass). With that information, you could set the exit temperature as a variable and solve for it at different pumping rates and determine whether you're able to maintain the antifreeze coolant at 160°F. That additional detail could lead to a higher or lower flow rate requirement, depending on how good the heat exchanger is, and how warm/cold the seawater is. There is, however, a theoretical pump capacity that is so low that no heat exchanger can help, and that is the pump rate where the seawater rises to 160°F (equal to the desired temp for the antifreeze coolant). At that point, no extra surface area will help you.]
Quote from: Ron Hill on October 16, 2021, 01:29:26 PM
The Sherwood pump (I found) is a bit more difficult to rebuild and the "C" clip that holds the compression in place was made of bronze!! I found that salt/brackish raw water slowly ate away at the bronze "C" clip just like - Jabsco found out with their bronze "C" at the bottom of their head pump.
I change that clip to SS and had eliminated that problem!! I passed that info back to DEPCO, but don't know if they use it or not?
A few thoughts
Ron
Why not pass your idea directly to Sherwood??
My suspicion is that Depco uses "genuine" parts.
Gee, I wonder why Sherwood doesn't smarten up and realize that bronze, not iron, pump bodies are the higher standard?????
Quote from: Jon W on October 16, 2021, 09:24:46 AM
Good thing the discussion is about cooling, because this conversation is getting hot. :rolling
Jon
Just wait till it morphs into wax vs. polyglow. That will be more entertaining because that's an even higher level of personal opinion and conjecture, zero fact. :rolling :rolling :rolling :shock:
Quote from: Jon W on October 16, 2021, 09:24:46 AM
Good thing the discussion is about cooling, because this conversation is getting hot. :rolling
Good thing this discussion is about M35 mounts. No thread hijacking here. Nothing to see, move on.
The original post was about M35 mounts, but the rather tense discussion the past few days was about cooling. Maybe you should comment to the folks that hijacked it.
Quote from: Jon W on October 17, 2021, 03:00:55 PM
The original post was about M35 mounts, but the rather tense discussion the past few days was about cooling. Maybe you should comment to the folks that hijacked it.
I just "evolved" the OP title to reflect the thread divergence. :D
Quote from: Stu Jackson on October 17, 2021, 05:44:58 PM
Quote from: Jon W on October 17, 2021, 03:00:55 PM
The original post was about M35 mounts, but the rather tense discussion the past few days was about cooling. Maybe you should comment to the folks that hijacked it.
I just "evolved" the OP title to reflect the thread divergence. :D
Thanks, I think that's the most constructive way to deal with our (my) inappropriate thread drift.
Regarding the characterization of our discussion as "tense", I see it as a very useful exchange of information from all involved. Some of us have strong views, and may poke each other by calling our own claims "fact" and others' claims "assumptions", but I still value the expertise and input from our members, even in cases where our views differ.
Back to the original topic of motor mounts, I finally made it down to the boat today and ran the motor in the slip with my wife shifting gears while I was below observing. I have a lot to unpack from that, including viewing some videos and pictures in zoom mode. I'm too tired to do that now (after 4 hours of driving and mowing 3 acres of our property). I'll report more details sometime soon. But bottom line, I am very concerned that spending up to $1200 on new mounts (of any variety) may not fix the problem. I think the problem might be mis-alignment of the stuffing box and/or hose, and possibly exacerbated by too-soft PTFE packing that allows the shaft to contact the nut. I loosened the hose clamps and tried to loosen the hose from the shaft log, but it wouldn't budge under gentle torque, and I didn't want to torque it too much for fear of my tool ripping into the rubber (or other catastrophe) while the boat is in the water. I have all winter on the hard to address this problem, so I may explore other less costly alternatives before plunking down for new motor mounts. I may also get a second opinion from another mechanic before haulout (if I can find one who is available).
Solving this problem had been rather urgent, because this Friday I was going to start a 2-day trip (mostly motoring) through the C&D Canal to bring the boat for haulout near my home. But for a few different reasons, I've decided to haul out in Rock Hall this year, so I'll have the boat in the water for another few weeks and no longer need to motor for two days and risk damaging my shaft - I'll just motor long enough to get in/out of my slip over the next few weeks.
Quote from: Breakin Away on October 16, 2021, 01:48:51 PM
• Required seawater flowrate = 198,000 BTU/hr ÷ [(0.95 BTU/lb-°F)*(30°F)*(8.7 lb/gal)] = 800 gal/hr = 13.3 gal/hr
Typo - 13.3 gpm.
Quote from: Breakin Away on October 16, 2021, 01:48:51 PM
it is plausible that the Oberdorfer cannot keep up in warm climates, and the Sherwood pump does.
Wrong. The Sw produces 11 gpm (if the curve is even correct, which I question but will go with it for this.) That is at ZERO head. Add Hx backpressure and the analysis goes further to heck.
I hadn't checked the assumptions or math/values and don't intend to. There's theory and there's real-world.
For the past 18 or so years I've been an OB dealer and have put 202M pumps on 4 cylinders (M4-30, M30, M35, M35B) including one on Soloman's and have not had ONE situation of not being able to adequately cool an engine.
Randy's has had ZERO problems with cooling, and I'd think his challenge is the same or more difficult than on the chessie. Additionally, the 202M has been put on C36s with no reported issue (agreed, N does not equal 95% of 202M pump owners but there have been none reported that I know of.) Witness that opposed to owners who have had snapped camshafts due to SW pump failures. Zero known/reported for Ob pump owners.
Note that Wb wants owners of Sw pumps to inspect the pump EVERY TIME before starting the engine. Do you (that is, "follow manufacturer recommendation" LOL :rolling :rolling )?
There's even more instances below of twisting what I had plainly written and/or putting words that I never said into my mouth, or drawing an incorrect conclusion from what I said re: both the pump and the mounts -- but I spend more time calling attention to/correcting them and the next post simply (intentionally?) creates more.
I'm not participating in that never-ending game anymore.
I do have a suggestion though. Instead of comparing the 35B to an M-25 (opposed to the XPB that also works excellently with the 202M pump) compare the 35B to the heat/power output of the Universal M-18, or even the M-12, or 5411. It will produce an even stronger, yet just as irrelevant, comparison. :shock: :shock:
Hxs require maintenance, as do pumps, and not doing so hoping that a pump will substitute for that would (IMO) define rather poor seamanship.
Do post once dissecting the cause of the mount/shaft/stuffing issue. Hopefully the mounts are not to blame.
I fully accept that many (most) users can install an Oberdorfer N202M-908 in their M35B (or a self-customized version of a less expensive version N202M) and be happy with it. I do think that it is also important to note that there is a small possibility that a new heat exchanger may be needed to get it to work properly, as it was in Mick Laver's situation: https://c34.org/bbs/index.php/topic,8689.0.html
Going forward, it will be interesting to see if Mick's problem reappears once his new heat exchanger has fouled a bit, and if/when that happens, whether boiling it out will fully restore the HX's brand-new performance.
Do you have any statistics (from C34, C36, and other users) on the percentage of shaft failures with the Sherwood pump? How many of those failures had the sleeve upgrade that was supposed to solve the problem? I still have an open mind, and your answers to this may affect my future decisions if my Sherwood needs another rebuild.
I haven't taken any meaningful poll but I know of 3.
One on a 35B (likely no ring, but uncertain,) one on a 4-30, one on a 25 or XP (no ring called for on those.)
Certainly maintenance on two of those 3 was probably an issue. But that also goes to the point of "Murphy" - so therefore it's better to have an Ob in case pump maintenance isn't up to snuff. Not an excuse, mind you, just common. Zero known issues with cooling a 4 cylinder.
Looking at it another way, the fact one needs a ring and needs to inspect the pump each start up says something about the product that's the root cause of the issue. Why Wb doesn't smarten up and have Sw make a bronze pump for them is beyond explanation. Sherwood makes other bronze pumps. If that did hen I'd wholeheartedly endorse using either one. The complicated parts is a downside but not a show stopper.
Quote from: KWKloeber on October 17, 2021, 01:50:23 AM
Gee, I wonder why Sherwood doesn't smarten up and realize that bronze, not iron, pump bodies are the higher standard?????
They did.
https://www.catalinadirect.com/shop-by-boat/catalina-310/engine/engine-cooling/pumps/copy-of-water-pump-late-sherwood-12quot/
Now the debate can begin anew. :razz:
AND! It's only a grand. Good deal.