Rebuilding Sherwood Raw Water Pump

[Sharpseadog]

I bought my 2007 Mariner 37 last summer. It had 430 Hours on the Cummins QSB 5.9 engine, but the water pump was failing as noted by Cummins service when PO had engine reprogrammed form 230 to 380 HP. Evidently that is common for these Sherwood pumps.

There was a new spare pump in the inventory (JMP P/N JPR-S7608) and I have installed it. I am considering rebuilding the OEM pump to keep as a spare.

I believe the pump on the engine was OEM Sherwood. The shaft will need to be replaced, as well as seals, bearings, wear plate, cam, etc. Has anyone rebuilt one of these? If you were able to obtain an overhaul kit, where did you get it? Or did you have to buy all of the parts separately?

 

[sdowney717]

I have rebuilt at least 6 Jabsco and some Oberdorfer engine pumps and all they needed were seal and impellers.

How do you know shafts and bearings are bad or are you guessing?

I have yet to replace a shaft or a bearing and can't imagine a sherwood could be that different. Since my engines are 1970 models, and I have owned boat sine 1998, go figure.

If so then I hope I never own a sherwood pump.

Found a repair PDF, they look very similar to Jabsco,
http://www.sherwoodpumps.com/FileAttachments/Marine-Distribution/en-us/MPG_3022_ENGLISH.pdf

 

[sunchaser]

SSD

If not done already, you may want to check out Seaboard's replacement pump for the less than staller Sherwood. Lots of discussion on boatdiesel over the years about this changeout and why.

 

[kulas44]

230 to 380 is a pretty big leap. More than "reprogramming" would be able to do ? I think I would need to see that first hand. The difference in the Cummins 6bta 250 and the 6bta 370 is substantial. Sure, you can turn the IP up but a lot of other things come into play besides that. Does the QSB have the same aftercooler from 230 to 380. Compression ratio ? I realize that the electronic controlled engines are more flexible in this respect, but Cummins is not known for adding parts for no reason. And yes, the sherwood pump is a POS, but would make a good spare.

 

[Jetstream]

As sunchasser has said the SMX pumps form Seaboard are a much more reliable and cheaper alternative to the Sherwood pumps that have a high failure rate.

I'm going to just replace the Sherwood's with Seaboard's SMX pumps when I get my 6BTA's and keep the Sherwood's as spares. I think I'll also install the raw water flow failure warning system just in case,

Brett

 

[Jay N]

The 1-1/2" Sherwood pumps have a long history of shaft failure. Don't know if the newer Sherwood pumps still have the same problem.

As noted by others, these failures prompted Tony at Seaboard Marine to design/manufacture a replacement that by all accounts is very reliable.

The 1-1/4" Sherwood M71 pumps (found on the older 210HP 6BT5.9 for example) did not share in the shaft failure. In fact, I've found the M71 to offer good service.

I just changed one out that went 3815 hours, the previous pump went 3253 hours. Impellers were replaced every 750 hours or so, new cam/backing plates after 2/3 impeller changes. I've rebuilt the first pump for backup. You can purchase assorted rebuild kits at any Cummins dealer, I get mine at Fisheries Supply. Redden or LFS might have them in Bellingham.

Sharpseadog, I was moored next to your new boat in Edmonds. Send me a PM.

 

[jleonard]

Definitely do the Seaboard upgrade You will thank yourself many times over.

 

[Pgitug]

Definitely do the Seaboard upgrade You will thank yourself many times over.

Had the PO install a new Seaboard raw water pump on their Cummins 2002 330 hp. Looks great. No leaks. A direct replacement.

 

[caltexflanc]

Depco Pump in Clearwater Fl sells rebuild kits and parts, or does it for you if you like. Very knowledgeable and helpful too. Worth giving a call.

Depco Pump Company Marine Catalog 111