Replacing Sherwood with Oberdorfer raw water pump, Universal 25XP

jtsai

Member II
The Sherwood raw water pump in the attached picture taken from a 1990 32-3 with Universal 25XP shows the pump is mounted inverted (with respect to the Sherwood brand label) and hoses are attached at the bottom of the pump with a 90 degree elbow to thru hull strainer. The Oberdofer 202M-16 replacement pump in the second picture shows multiple engine mounting orientation options. Will the Oberdofer pump attach to 25XP engine block in the same orientation as the Sherwood and requires no modification to hose and elbow? Thank you.

Jeff
Ericson 32-2, Ardea
New Bern, NC
 

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Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
When I changed from the (backwards, ridiculous) Sherwood to Oberdorfer on an M25, it was very straightforward and I used the existing bronze fittings.
 

jtsai

Member II
Thank you Christian, that is good to know. Looking forward to your next vide.

Jeff
Ericson 32-2, Ardea
New Bern, NC
 

Bolo

Member III
Glad to see this posting cause I've been thinking on changing my Sherwood to Oberdorfer pump for awhile now. I agree with Christian. Sherwoods are like having car wheels with the lug nuts on the inside instead of the outside. Dumb. What is the correct Oberdorfer part number for use on a M25XP?
 

jtsai

Member II
There is a national shortage of Oberdorfer pumps due to pandemic, all suppliers have at least 4 week back order.

I do have a question about the Oberdofer N202-M16 (1/2" ports) as a direct replacement for the backward Sherwood pump on the Universal 25XP. The intake from the raw water strainer to the pump has 1/2" hose and the output to engine cooling has 7/8" hose (as shown in the attached picture). Is this a standard setup? 1/2" hose at intake side and 7/8" hose at output side but pump has 1/2" port at both intake and output?

Jeff
1990 Ericson 32-2, Ardea
New Bern, NC
 

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Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Here's a photo of both pumps from my M25. Hard to tell if the sizes are different--they do look different to me. .

However, I specifically remember the bronze fittings swapped each for each. (The brass elbows in the photo were temps, since I needed a vise before I could reuse the original bronze ones. No brass in salt water).

two water pumps.jpg
 
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debonAir

Member III
There is a national shortage of Oberdorfer pumps due to pandemic, all suppliers have at least 4 week back order.
I do have a question about the Oberdofer N202-M16 (1/2" ports) as a direct replacement for the backward Sherwood pump on the Universal 25XP. The intake from the raw water strainer to the pump has 1/2" hose and the output to engine cooling has 7/8" hose (as shown in the attached picture). Is this a standard setup? 1/2" hose at intake side and 7/8" hose at output side but pump has 1/2" port at both intake and output?

Jeff
1990 Ericson 32-2, Ardea
New Bern, NC
I have a spare brand new Oberforfer pump in my shed I can send you for the retail price + shipping, if you are in bind. Its the model with 5 mounting holes like in Christian's picture above.
 

Tom Metzger

Sustaining Partner
Interesting. I read this thread and thought that N202-16 doesn't sound familiar. So I looked up what I put on my m-25XP several years ago. It was a -15 with 3/8" ports. I was curious why I would buy a pump with reduced ports. Further searching brought me to a "Fast moving parts" list that showed the -15. The hose barb couplers fit so the list was correct.
 

jtsai

Member II
Tom, that is disconcerting. Here is the CatalinaDirect web site for the N202-M16 (1/2" ports): https://www.catalinadirect.com/shop...mp-replacement-or-retrofit-12quot-oberdorfer/

Looks like the only way to be sure is removing the Sherwood pump and make careful measurements.

debonAir, thank you for the offer on your spare but I am OK waiting for back order. The Sherwood pump is still working fine but I want to swap it out after my friend had a near catastrophic experience last week on their Catalina 34 with this pump. According to him, the Sherwood raw water pump is not entirely bronze and the weep hole was blocked by rust and forced seawater into the engine block. He discovered milky fluid when checking oil level. His delivery trip went down hill from that point.
 

Baslin

Member III
I just ordered a Moyer Marine raw water pump to replaced my leaking Oberdorfer. It uses the same impellar but has an O-ring instead of paper gasket and it has nice incapsulated thumb screws for easy replacement. They have them in stock. You may also have to order the adapter plate to convert to a 2 bolt system if your engine doesn't already have it. They have those in stock as well.
 

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Tom Metzger

Sustaining Partner
I just ordered a Moyer Marine raw water pump to replaced my leaking Oberdorfer. It uses the same impellar but has an O-ring instead of paper gasket
The Oberdorfer pump has an O-ring seal and for the difference in price I had no problem with the large heads on Phillips head screws. I not only carried a screwdriver, I also had snap ring pliers on board.
 
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