Raw Waterpump Mount Drip - Slow Drip

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Seaview
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Raw Waterpump Mount Drip - Slow Drip

Hey Guys, 
  We just finished replacing the impeller on our M35B (Late Sherwood). When we were inspecting the pump to ensure nothing was leaking, we noticed a small slow drip coming, not from the water pump, but from what seems to be a weep hole? on the water pump mount. Picture Below.

There seems to be holes located around that mount as pictured (circled red below from the parts manual). If water is leaking from there (approx. 1 drop every 2 minutes while engine is in operation) does that mean that there is an issue with the pump seals (circled in red) or the mount (circled in blue) ? 

Any help as appreciated as we are unsure what would be causing it.

Thanks!
 

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Sojourn
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Yes, could be either.  The corrosion would worry me.  Time for a new pump.

Lou Bruska
Sojourn
1985 C-36 Mk-I TR #495
Eldean Shipyard
Lake Macatawa (Holland, MI) Lake Michigan
Rallyback@comcast.net

Seaview
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Pump or pump mount? The pump where the impeller is housed seems good, no corrosion there. I cant seem to find the part number for the pump mount shown in the picture which has corrosion on it. 

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pkeyser
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Water coming from the weep hole means one seal is shot and you potentially have only one seal left preventing water from entering the engine and ruining it. (The second seal too may have failed). The pump needs rebuilding, but I agree with Lou- it looks rusty enough to replace the whole unit...maybe with an Oberdorfer upgrade?

Check the engine oil and see if you discover some milkiness. That's a sign of water mixing with oil and it would need to be replaced immediately.

Weep holes are designed in to give you visual conformation that the seal immediately adjacent the impeller has failed.

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

Seaview
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Thanks for the info, we just changed the oil and did not see any milkiness. That being said we just winterized the engine today so could the replacement wait until the spring? If there is water in the oil do we just pump everything out or drop the pan? And Finally does the Oberdorfer do well with the M35B, has there been any overheating issues with it?

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Haro
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Please view my website on my signature to see how easy it is to install Oberdorfer. Seals are easy to replace, also on my website.  All is needed is a steering wheel puller to remove and install the seals. Also view the album.  PM me if you have questions. 

Seaview
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Thanks Haro! Does the Oberdorfer perform as well on an M35B? Also, if 1 seal is shot, being that we have just winterized could this wait for Spring or are we at the risk of ruining something extremely expensive? Thanks in advance

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Haro
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Yes, it performs as well. If you would rather work on it later, you may consider removing the pump from the engine by disconnecting the 2 bolts that holds it to the engine and separate it away from the engine and cover  that part of the engine with a plastic bag to prevent any water entering the engine that drips out of the water pump.
visit link below
https://www.catalina36.org/forum/technical-discussion/oberdorfer-seals-r...
 

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EUREKA
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I will replace without any doubt. JMP manufactures marine pumps as OE for many engines. We installed one and works perfect, I'm not sure the oberdorfer has the same flow as the original Sherwood, you can find it, in many places. www.jmpusamarine.com
Just a thought.

Eladio Vallina

C-36 TR EUREKA II
Hull 1122 (1991)
Home port Barcelona (Spain).

Seaview
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Which JMP Model did you buy? Seems like there are none available on that site for a Universal M35B

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pkeyser
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We have an M35B and converted to Oberdorfer many years ago. No problems with flow/increase in engine temp at all. Used P/N N202M-16. Needed to notch the base with a dremel and remove some material from one of the nipples during installation. I think if you research this site, you'll find a slightly different Oberdorfer pump with very little to no mods required.

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

Seaview
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Great info, thank you all so much. I think we will end up going with the Oberdorfer and just buying the pre-modded one. I must ask, is there no way to just buy the enclosure for the sherwood? I mean everything else on the pump is good, seems like just the enclosure needs to be swapped out with a brass one. I hate to replace the entirety of the pump if all i need are seals/enclosure? If they only sell it as one piece id rather pay the 400 for the Oberdorfer than the 1200 for the all brass Sherwood. Sheesh that price.

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EUREKA
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Posts: 106

Our engine is M35A, row water pump looks to be different to M35B, I guess you can ask JMB pumps, they are all full bronce and around $400.
We bought the pump from www.bigblueoceanmarine.com you might want to ask them.

regards 

We bought at 

Eladio Vallina

C-36 TR EUREKA II
Hull 1122 (1991)
Home port Barcelona (Spain).

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pkeyser
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Half the Sherwood pump housing is Bronze and the other half cast iron. I don't believe they make a bronze replacement for the cast iron part, but you could research.
Try cleaning the rust up and see if everything pulls apart goes back together cleanly. However, If memory serves me, the seals are in the cast iron part. If they are badly corroded in place, when you remove them, the seal seat will likely be damaged and allow water to pass around the outside of a new seal. 
 

Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B

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