Sherwood Water Pump replacement with Oberdorfer on M25XP

[BlindAmbition]

I know this topic has been discussed on the forum, but I did not notice my particular question. I purchased a 1990 C34 this June. The surveyor and I noticed some water leakage at the Sherwood pump. My engine is the M25XP. I ordered the Oberdorfer replacement. Today I finally got around to doing the swap. However, after removing the Sherwood, I noticed that only 2 of the bolts from the Sherwood thread into the Oberdorfer and onto the engine. The other 2 holes in the engine are different and I am not sure they are designed for a bolt. I think I may have not paid enough attention (and did not take a photo) before pulling the Sherwood. I know the Sherwood had clamps that held it on. Should I use those on the Oberdorfer as well?

Also, the only way the Oberdorfer fits with holes lining up, etc. is with the Oberdorfer sign upside down and the intake and outtake facing in different directions than the Sherwood did. I want to make sure the hose that went to the upper part of the Sherwood also goes to the upper part of the Oberdorfer.

Finally, because the flanges are located differently it appears my old hoses might not fit/make it. Did anyone else run into that issue?

Thanks for any help. Well aware I am a glaring novice.

[KWKloeber]

I know this topic has been discussed on the forum, but I did not notice my particular question. I purchased a 1990 C34 this June. The surveyor and I noticed some water leakage at the Sherwood pump. My engine is the M25XP. I ordered the Oberdorfer 908 replacement. Today I finally got around to doing the swap. However, after removing the Sherwood, I noticed that only 2 of the bolts from the Sherwood thread into the Oberdorfer and onto the engine. The other 2 holes are different and I am not sure they are designed for a bold. I think I may have not paid enough attention (and did not take a photo) before pulling the Sherwood. I know the Sherwood had clamps that held it on. Should I use those on the Oberdorfer as well?

Also, the only way the Oberdorfer fits with holes lining up, etc. is with the Oberdorfer sign upside down and the intake and outtake face in different directions than the Sherwood did. I want to make sure the hose that went to the upper part of the Sherwood also goes to the upper part of the Oberdorfer.

Also, because the flanges are located differently it appears my old hoses might not fit/make it. Did anyone else run into that issue?

Thanks for any help. Well aware I am a glaring novice.

The Ob 908 is not the replacement pump best suited for the M25-XP, First, it's way overpriced. It's the replacement pump for the XPB and M-35B.   Whoever sold you the 908 for the XP doesn't know what they're doing.

PM me off list if you like we can get back on the right track.
Ken

[KWKloeber]

What you have is not the 908, but the N202M-16 pump -- the correct replacement for the XP (but severely overcharged for it). 
It bolts on with 2 bolts (you can use the sherwood bolts, though when I ship these I include a stainless steel stud/nylock flange nut kit so that you are not threading into and torquing the crappy gear cover, but using "permanent" studs installed in the gear cover.  Also the Kubota gasket is much better than the Westerbeke gasket.

The engine land is for an hour meter on the tractor (actually the M-25XP base block is an industrial motor), so with the pump, two of the holes are blocked with M6 set screws.  You use the other two.  There is a slight mod needed to the pump base and elbows.  See
"Replacing a Sherwood Water Pump with an Oberdorfer"  on the TechWiki under Engine > cooling topic.  If you have questions after that let me know!

ken

[BlindAmbition]

Thanks. I was worried about the 2 bolts, so that makes me feel better. The slight mod makes sense the way the pump and the elbows were facing seemed off. Will take a look at that Wiki, must have missed that specific one when I was digging around.

[John Langford]

Ken
You wrote: "What you have is not the 908, but the N202M-16 pump -- the correct replacement for the XP (but severely overcharged for it)." Clarification please. Are you suggesting that the pump is overpriced or that the owner of Blind Ambition was overcharged by an unscrupulous retailer? I paid around $250 for my N202M-16 three or four years ago. The crappy Sherwood pump it replaced was overpriced then and is even more so now that Westerbeke seems to monopolize the sale of them.

[KWKloeber]

john

let me walk a fine line here.

The n202m-16 (and -15) pump lists for $270.
There are 2 well-known and oftentimes herein-referenced marine parts websites who sell the pump for $293, and $310.  They are not happy with making 100% of the dealer mark up, they charge owners list plus (sometimes 10% surcharge, usually 15%, and 20% if they can get away with it. 

Most retailers nor I do that, and I think it's "just plain wrong" to take advantage of unknowing owners.  For assn members the pump is $243.

yes, the sherwood G908 is bound up by westerbeke and is overpriced, and so is the Oberdorfer M-908, because they are taking the same M-16 pump before the base is drilled, turning it down to the round base, and selling it for $138 more just because of westerbeke's monopoly on the sherwood pump price.  I have tried to buy the undrilled-base M-16 pumps to make replacements for the B-series engines (xpb. 35b) and Ob won't sell them.  Shortly after I posted this
http://c34.org/bbs/index.php/topic,8148.msg56869.html#msg56869
and showed it to Depco pump, Oberdorfer miraculously came out with it's sherwood replacement.  What a coincidence that was.

ken

[Hawk]

Ken,

I have a 34 with the M35B. I replaced the Sherwood pump with another G908. It is now leaking. In Vancouver a new one is CDN $1100 from the Westerbeke monopoly. In the US I see they are $850 thereabouts...same price.

You mentioned in you last post the Oberdoffer replacement. Is that the Oberdorfer 908?  Are you selling these? May I PM you?

Many thanks,
Tom

[KWKloeber]

Tom,

Yes the straight replacement is the clip-on Oberdorfer N202M-908.
You can also get away for less money using the flanged base pump N202M-16, and doing the mod so it's bolt on rather than clip on.

Sure, email me and I can explain more detail/particulars.
KWKloeber@aol.com

kk

[Hawk]

Thanks Ken! I'll mail you. I've reviewed the Tech Wiki that nicely sets out the mod which is a bit more involved for the M35B. I see it appears one needs to re-route the hoses as well.

Anyway I'll speak to you shortly. Always nice to have this source of information in the website.

Tom

[KWKloeber]

Tom

Using the modded-base vs the round-base Ob pump makes no difference regarding the hoses -- you reuse the same set up from the SW pump.   The TW article doesn't explain it real well -- it combines photos of putting Ob pumps on both the M-25/XP/XPA engines and the B-series engines like yours.  It really would be easier to follow if it were two separate articles.

It's just a matter of the round-base pump (M-908) being clipped on like the SW pump, or the bolt-on base (M-16) being cut down so it can fit onto the land on the engine (which is actually for a mechanical hour meter on Kubota engine applications.)

I attached photos of each on a B-series engine.  Ignore the strange hose barbs -- that was testing out some alternates.

The circumstances surrounding the beta testing is convoluted (but since you asked :-) ))

4-5 years ago I decided to put together plug/play replacements for the Sw pump on the B engines, and after machining and much testing, came up with a bolt-on pump (similar to what others did) and a round-base clip-on pump (basically identical to the Sw.)  I beta tested both on a C-30 XPB engine.  But, making them from the pre-drilled-base Ob pumps was clunky, but I was assured I could buy undrilled pumps direct from Ob, which would have made things easier/neater/cleaner.  I figured that I could do the mod for about 30 bucks.

Fast forward to my showing Depco a pic of both of "my" pumps.
Fast forward 6 months more to Oberdorfer starting bringing the M908 clip into it's line up. Some coincidence, 'eh?

I'll reply to your email,

ken

[Noah]

Hey guy how about move this topic in to it's own topic as you have moved away from the 25XP discussion.

[KWKloeber]

Stu will have to move this discussion et. al. to a new topic "xpb" , Noah, I don't have credentials/ permissions to do that on the forum.

k

[kwaltersmi]

I launched today with my M25 XPB and the Sherwood pump is leaking. After opening it up to check the impeller, it looks like the rubber on the seal (Parts 10 through 12 - 30288X) was torn and was coming out.  It dripped about 1 drop every 2 seconds at idle on launch, but quit dripping altogether once I was underway for the 3 mile motor to my marina. No dripping when I arrived at my dock.

So...

Should I replace the seal in the Sherwood pump?  Is this difficult to do?  Should I swap in the Oberdorfer (is it 908?) pump instead? Should I leave it alone and wait for it to leak again even though part of the rubber from the seal came out of the pump when I opened prior to motoring to my marina?