Gang,
I put in a new Sherwood G908 on my M35 back in November and have maybe 30 hours on it. My old one was rebuilt and I got about 200 hours before it started weeping so I got a new one and kept the old as a spare. I usually check the engine compartment before every outing and noticed a couple of drops of salt water and a rust stain from the lower weep hole on the Sherwood. I called up my local vendor and to see if there is a warranty or anything and they suggested I check for water flow restrictions that could be causing too much pressure build up. She's pumping lots of water and keeping my engine right at 160. I've never heard the water flow restriction explanation on the weeping, anyone else heard this?
JR,
When you put the new pump in, did you/it also include new seals?
FYI, Ken Kloeber has provided a very good primer on Sherwood pumps which can be found in the tech wiki.
Quote from: Joyride on January 30, 2017, 07:56:45 PM
Gang,
I put in a new Sherwood G908 on my M35 back in November and have maybe 30 hours on it. My old one was rebuilt and I got about 200 hours before it started weeping so I got a new one and kept the old as a spare. I usually check the engine compartment before every outing and noticed a couple of drops of salt water and a rust stain from the lower weep hole on the Sherwood. I called up my local vendor and to see if there is a warranty or anything and they suggested I check for water flow restrictions that could be causing too much pressure build up. She's pumping lots of water and keeping my engine right at 160. I've never heard the water flow restriction explanation on the weeping, anyone else heard this?
The Rx = Oberdorfer :D
Quote
I put in a new Sherwood G908 on my M35 back in November
I don't know how warnings are on the forum...... about ditching Sws and install Obs. Before the shaft seizes and causes a broken-off fork on the cam shaft and a mechanic's bill, as other M-25, XPB, M3-20, M-35B and M-40B owners have had.
kk
Actual M-35 (or maybe it was an M40-B) owners's aftermath photo....
From the tech wiki:
Why SHERWOOD Raw Water Pumps leave a LOT to be desired: http://c34.org/bbs/index.php/topic,8493.msg59876.html#msg59876 Thanks to Ken for that one, I'm tired of repeating it. - Stu 5/25/2015
I read the tech wiki article on replacing the sherwood with the oberdorfer. The article references the M35 A and B and the pump modifications needed for each one...not clear to me what modifications are necessary to fit the Oberdorfer to an M25XP?
Thanks,
Ken,
Last time you posted on this convinced me to make the change back to the Ob (Hansen Marine had replaced my weeping Ob a number of years back with the Sw). Timing is good since the Sw was starting to show signs of weeping. I've got a m25xp. Was there a standard shaft type used on the m25xp? Or do I need to pull off the Sw to determine before ordering? I just don't remember from changing out the impeller back then. If so, won't be be doing that for another month or more.
Thanks,
Ed
Quote from: Ed Shankle on February 01, 2017, 10:04:25 AM
................
..................I've got a m25xp. Was there a standard shaft type used on the m25xp? Or do I need to pull off the Sw to determine before ordering?
Ed,
In this write up of rebuilding an Oberdorfer, I included photos of the shaft and the insides. See replies #6 & #12.
Oberdorfer Pump Rebuild 101 - http://c34.org/bbs/index.php/topic,6766.0.html
IIRC, only the older M25s had the male/female shaft issue. Your M25XP should be fine and agree with the photos in the link.
If you don't remember having to remove the pump to reinstall the shaft, and you just slid the new shaft on, you should be fine.
If you always had someone else do the work, then you may not know.
Ken's reply #13 in that link discusses your question, too.
Ed,
Following up on Stu's.... I have not seen an XP that had the female-shaft Ob 202M-03/-07 pumps.
My 84 C-30 M-25 did (with the required adapter plate for that set up,) but regardless, the M-25/XP/XPA, pump lands and camshafts are all the same (NOT SO for the XPB, M35B/40B.) It's simply that Universal used the adapter plate and a female-to-male shaft adapter to install the -03/-07 pumps (couldn't buy enough of the 202M-15/-16 pumps to keep up w/ engine production demand.)
So, the short story is, regardless of what WAS on there, the MALE shaft will fit your engine pump land and camshaft.
Whether you have 1/2" NPT or 3/8" NPT hose barb elbows is a question. I recommend the 1/2" pump to customers but my M-25 has had the 3/8" pump for 32 years. If your Sw is "standard" the hose barbs **should** be 1/2", but...... Also I have a kit to replace the Sw clip bolts with stainless steel studs and nylock flange nuts.
PM me your email address and a few pics if you have them, that always helps define things.
cheers
Ken
Quote from: mainesail on January 31, 2017, 03:52:39 AM
Quote from: Joyride on January 30, 2017, 07:56:45 PM
Gang,
I put in a new Sherwood G908 on my M35 back in November and have maybe 30 hours on it. My old one was rebuilt and I got about 200 hours before it started weeping so I got a new one and kept the old as a spare. I usually check the engine compartment before every outing and noticed a couple of drops of salt water and a rust stain from the lower weep hole on the Sherwood. I called up my local vendor and to see if there is a warranty or anything and they suggested I check for water flow restrictions that could be causing too much pressure build up. She's pumping lots of water and keeping my engine right at 160. I've never heard the water flow restriction explanation on the weeping, anyone else heard this?
The Rx = Oberdorfer :D
This is the best advise without all the extra blather.
Ken : You might want to tell the whole story and mention that Westerbeke came out with a Service Bulletin that called for installing a free sleeve to prevent the problem in your above picture for the M25XPB and M35BC engines !!!!!!!!!!!!
It was a few years ago, but that bulletin was published in the Mainsheet Tech Notes and publicized / mentioned in Practical Sailor.
A thought
Quote from: Ron Hill on February 01, 2017, 02:56:18 PM
Ken : You might want to mention that Westerbeke came out with a Service Bulletin that called for installing a free sleeve to prevent the problem in your above picture for the M25XPB and M35 BC engines !!!!!!!!!!!!
A thought
Ron
I think you did just mention it. :d Go ahead and add it to the wiki article, but in full disclosure be sure to explain that it doesn't
prevent the problem, it only
covers it up.
If band aids are the answer, go for the Sw. My though is that it makes sense to avoid the problem in favor of a superior product that's made for the marine environment (yes, a real bronze body) and doesn't seize up (with a crappy iron body and double the number of parts)!!!
P.S., in full disclosure, Wb never paid for damage to engines BEFORE it found out its pump is crap and seizes up, AND no longer offers the free band aid to prevent the effect of its pump seizing up.
ken
Ken : You might want to read that service bulletin!!
A thought
Quote from: Ron Hill on February 01, 2017, 03:32:12 PM
Ken : You might want to read that service bulletin!!
A thought
Ron I have read every SB for every Universal and Westerbeke Propulsion engine (not just the B series) and published them on the wiki.
What's your point in plain english?
I should also clarify that, the SBs do not mention, nor acknowledge damage to the camshaft on the M-25/XP/XPA, nor reinforcing ring band aids for any engines other than the B series. The last damaged camshaft due to the Sw pump seizing (snapped off the fork) that I personally know of, was on a Universal M3-20.
Ken
Roland,
First, don't let the "C", as in M-25XPAC, etc. confuse you. It simply means that the engine has a different, i.e., Catalina ("C") wiring schematic.
The M-25, M-25XP, M25-XPA (and virtually ALL Universal engines EXCEPT the newer B-series (M-25XPB, M-35B, M-40B) involve the very simple mod to the base of the Ob pump (takes about 5 minutes) shown in the first part of the article.
The B-series engines are a completely different animal and two different Ob pumps can be used.
Additionally, using the same hose barb elbows from the Sw pump, there is another simple mod (takes 4 minutes) because the inlet/outlet of the Ob pump is slightly closer together than on the Sw pump.
PM me your e-dress, and I can email you more info.
Ken
Quote from: Roland Gendreau on February 01, 2017, 09:52:46 AM
I read the tech wiki article on replacing the sherwood with the oberdorfer. The article references the M35 A and B and the pump modifications needed for each one...not clear to me what modifications are necessary to fit the Oberdorfer to an M25XP?
Thanks,
Thanks Ken, PM sent.
All,
THank you for the responses. I brought the new pump in to the shop (reputable in St. Petersburg FL) they pressure tested the new sherwood and couldn't get it to leak so they are saying that I might have a restriction in the flow. My strainer looks good and I did pull some zinc out of the hx which would inhibit but I don't think much. Would there be anywhere else where I'd be getting water flow issues besides the hx? The hx exit hose is new (replaced due to cracking last year but didn't see much if any build up.)
would the waterlift potentially have build up or does anyone have a suggestion? Even if I go to the Ob pump I would still like to understand this better.
You might check the raw water injection fitting into the exhaust. There could be some buildup there. Also, when you had the starboard endcap off the HX, were the hose fittings clear as well? I was surprised to find one of mine over 50% obstructed by salt precipitation last fall.
Craig
Quote from: Craig Illman on February 03, 2017, 12:18:46 PM
You might check the raw water injection fitting into the exhaust. There could be some buildup there. Also, when you had the starboard endcap off the HX, were the hose fittings clear as well? I was surprised to find one of mine over 50% obstructed by salt precipitation last fall.
Craig's right. The inlet port where the cooler salt water hits the hot water in the HX is notorious for salt buildup. I've been commenting on this for years, ever since I removed our old HX in 1998. Do a search on "Mariachi" :D Sorry, I just did, so it must have been in one of my older tech notes, when I removed my 2 inch HX and cleaned it out, also found what Craig described. I shook it and it sounded like a mariachi band! :clap
But you really have to do a SYSTEMATIC analysis, rather than asking "where else to look?" The H2O comes in through the thru hull and goes out through the exhaust at the transom. Check everywhere in between.
So that begs the question -- what pressure did they run on it?
Hopefully equal to or higher then it can put out. And if there was no leak past a seal, then even if there was a TOTAL obstruction, say in the Hx, the pump **won't** leak.
I'd remove and/or in-place test the flow thru the Hx to see if it has an obstruction or significant pressure drop.
kk
Quote from: Joyride on February 03, 2017, 11:17:31 AM
All,
THank you for the responses. I brought the new pump in to the shop (reputable in St. Petersburg FL) they pressure tested the new sherwood and couldn't get it to leak so they are saying that I might have a restriction in the flow. My strainer looks good and I did pull some zinc out of the hx which would inhibit but I don't think much. Would there be anywhere else where I'd be getting water flow issues besides the hx? The hx exit hose is new (replaced due to cracking last year but didn't see much if any build up.)
would the waterlift potentially have build up or does anyone have a suggestion? Even if I go to the Ob pump I would still like to understand this better.