swapping out Sherwood pump for new Oberdorfer
- Thread starter c130king
- Start date
Jim,
Have you looked at the Catalina 34 International website? There is extensive information about this.
Have you looked at the Catalina 34 International website? There is extensive information about this.
I didn't. The issue was figuring out how the Oberdorder mounted to the motor. The 5 holes in the Oberdorfer mounting plate don't line up with the 2 holes in the motor.
Called DepcoPump and they told me that holes would have to be drilled in the mounting plate to line up with the motor mounting holes. This is a 1/4 - 1/2 inch brass plate. I don't have that capability.
Old Sherwood was shot...long story which I may fess up to on this forum someday...;-)
Anyways needed a pump installed that day. Went to a local marine hardware store in Gulfport, MS (not a West Marine) and believe it or not they had a brand new Sherwood Pump (same model) in stock. The guy at the store couldn't even believe it. He is pretty sure somebody ordered it a while back and never returned for it. So I bought it and installed it in about 20 minutes. Works perfectly.
Of course the Oberdorfer was $229 and the Sherwood was $560 (he sold it to me for the price he bought it from DepcoPump). Going to try and return the Oberdorfer. New Sherwood runs flawlessly. Have some pictures of pumps and mounting holes which I will post later.
Cheers,
Jim
Called DepcoPump and they told me that holes would have to be drilled in the mounting plate to line up with the motor mounting holes. This is a 1/4 - 1/2 inch brass plate. I don't have that capability.
Old Sherwood was shot...long story which I may fess up to on this forum someday...;-)
Anyways needed a pump installed that day. Went to a local marine hardware store in Gulfport, MS (not a West Marine) and believe it or not they had a brand new Sherwood Pump (same model) in stock. The guy at the store couldn't even believe it. He is pretty sure somebody ordered it a while back and never returned for it. So I bought it and installed it in about 20 minutes. Works perfectly.
Of course the Oberdorfer was $229 and the Sherwood was $560 (he sold it to me for the price he bought it from DepcoPump). Going to try and return the Oberdorfer. New Sherwood runs flawlessly. Have some pictures of pumps and mounting holes which I will post later.
Cheers,
Jim
Yeah. I made this swap 2 years ago. I had to cut the base with an angle grinder and drill a new hole. It took about an hour to do the work. Well worth it in my opinion bc the ober is a better pump and the impeller is easier to change.
Yes, I agree that the pump design of the Oberdorfer looks much easier to change out the impeller. But I have changed the impeller now 3 times on my old Sherwood so while a bit of a pain it can be done.
But I don't have the skills or tools to grind the base plate and drill holes in a thick brass plate.
Was thinking about keeping the Oberdorfer and finding a friend that could do that but this Sherwood pump should last for a good long time so I will just return it.
Cheers,
Jim
But I don't have the skills or tools to grind the base plate and drill holes in a thick brass plate.
Was thinking about keeping the Oberdorfer and finding a friend that could do that but this Sherwood pump should last for a good long time so I will just return it.
Cheers,
Jim
Jim, what engine do you have? The drilling is required for M30 and M35 engines, not M25 series engines.
And the reality is the Sherwood simply won't last you a good long time, since it's built from inferior materials compared to the Oberdorfer.
Good luck, glad you learned how to deal with it, though.
And the reality is the Sherwood simply won't last you a good long time, since it's built from inferior materials compared to the Oberdorfer.
Good luck, glad you learned how to deal with it, though.
Stu, the C310 has the M25-XPBC. That model is slightly different than the M25. You do have to modify the base of the ober pump to get it to work.
Here are the pictures I took Friday. With the Sherwood removed you can see the 2 mounting holes in the frame of the motor. And then you can see the 5 holes in the mounting plate of the Oberdorder. They will not line up.
Just thought folks might like to see these.
Cheers,
Jim
Just thought folks might like to see these.
Cheers,
Jim
Attachments
Thanks, Jim. Yup, our rw pumps are in completely different places, ours is lower end, starboard side, yours is port side, high. Good luck.
Jesse, Do you have any more advice/pictures of the Oberdorfer pump modification/installation?
I'm assuming the newly drilled hole will need to be close but not "perfect". As in the pump seems to have a rim/ridge that centers the tang.
Did you have to cut the other portions of the base off?
Did you have to buy different bolts to mount it?
When installing it, did you keep it loose and start the motor to center it? Like the manual said to do with the Sherwood pump?
I noticed on your web site you used a few elbows to get the hoses to line up. Do you think you could have done it with fewer if others were available?
Again any other advice would be much appreciated. I just went to change my impeller yesterday and found the housing of the Sherwood leaking...
Thanks, MM
Here is the thread on when I made the switch. http://forums.sbo.sailboatowners.com/showthread.php?t=139566&highlight=sherwood
To answer some of your questions, I used tracing paper and a pencil to make a template of the mounting and bolt hole locations. I then cut the base with an angle grinder to match and made the bolt hole (used one of the existing bolt holes).
I did buy some new bolts to use. I wanted them to be a little longer than the ones on the Sherwood pump. I got SS bolts from the bolt depo (local store that sells good quality bolts).
I had the cover off while I was installing the pump and found it was easy to give the impeller a little spin to get the pump and motor aligned.
The way to cut down on the elbows/fittings is to use the N203M-16 pump. That will have larger openings (3/4" I think?, same as the Sherwood pump). I discovered after I already started to alter my pump that I had the N203M-15 and that has smaller openings.
Hope that helped. Let me know if you have any other questions.
Good luck and fair winds.
Jesse
Sherwood Water PUmp Failure
Wish I would have joined the web site 3 months ago. I have had 2 Sherwood failures since buying the boat new. The first after 327 hours and the second after only 167. I wish I would have know about the "Oberdorfer Option" before giving the OK for another Sherwood installation.:cry: