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have approx. 1999 cummings 6bta's rebuilt (not factory) in 2002. engines have 700 hrs since rebuild, 90 of them with me since november. had both sides impellor failure within 3 hours. one side was approx 90 hours (7 months) old, the other side had an extra year and estimated additional 20-30 hours. would anyone suspect some external force having something to do with these failures or is this common to have both sides go out within a couple of hours (the couple of hours did span 10 days and one more use of the boat).

had the boat tied in slip (4.5 feet of water) and in gear while adjusting fuel pump idle 2 days before 1st failure. could kicking up mud have anything to do with this. no strainers other than external grills on the intake.

no strainers other than external grills on the intake.

Therein lays your problem....

Raw water strainers are a must for any supply that is going through a pump, regardless of whether the pump impeller is vane or rubber style. The grill openings don't stop any debris smaller than about 1/4".

See: External Raw Water Strainers

I plan on redoing my raw water intakes this winter as I feel the plywood backing plates have reached the end of there useful life.

I perfer the original setup of scoop strainer and internal sea strainers.

Looking for recommendations for backing plates, strainer with thru-hull or seperate, perko,groco, or buck-algonquin?

The factory impellers and other internal parts on the Sherwood raw water pumps have declined in quality over the years to the point that an impeller may only last a few hours or weeks. Likewise the factory wear plate and cam are garbage. Tony Athens with Seaboard Marine in CA solved the problem by commissioning the manufacture of aftermarket impellers and internals to his specs....They are 100 times better than the crap Sherwood is putting out now. I rebuilt both my Sherwood 15000 pumps on my 1989 6BTA 250s a few years ago using Tony's parts and have had zero problems. The stock ones dry rot and the impellers just explode....plus the stock cam is too hard and wears unevenly, creating a razor edge that shreds impellers...and the wear plate is crap.

Anyway, go with Tony's stuff and you can rest easy....but nothing will save an impeller that runs dry.

UV

thanks capt pat. discussed that with my mechanic who said the probable reason that it didn't have strainers was becuase he couldn't see any way to fit them in. decided on 2 new sherwoods, old pumps turned out to be in terrible shape once removed. hoses were in bad shape so replacing now. mechanic having a heck of the time getting the hoses back in because they were routed thuo a piece of pvc in the main stringer. o.d. of hose almost the exact same size as the i.d. of the pvc. mechanic did say that he thought the holes on the outside strainer would be very close to the same size as an inboard strainer just no way to clean them. seems like a great time to install strainers.

vic, i will make sure and rebuild with the athens parts when the time comes.

thanks for the input.

Wlbr

I kept the internal stainers. When we redid the companion way supports, we ran a couple of cross braces and hung them from there. I little tight but they are easy to get at. Just pick up the deck hatch's any there you go.

Craig

For backing plates, we glassed in a half inch fiberglass plate. By the time we glassed in the plate and added matting we must have a backing plate between 3/4 inch and an 1" thick. My sea cocks are Groco with the pop out plug so you can winterize and use them as for a crash pump.

wlbsr wrote:thanks capt pat. discussed that with my mechanic who said the probable reason that it didn't have strainers was becuase he couldn't see any way to fit them in. decided on 2 new sherwoods, old pumps turned out to be in terrible shape once removed. hoses were in bad shape so replacing now. mechanic having a heck of the time getting the hoses back in because they were routed thuo a piece of pvc in the main stringer. o.d. of hose almost the exact same size as the i.d. of the pvc. mechanic did say that he thought the holes on the outside strainer would be very close to the same size as an inboard strainer just no way to clean them. seems like a great time to install strainers.

vic, i will make sure and rebuild with the athens parts when the time comes.

thanks for the input.

If it not to late listen to Vic and return the Sherwoods and buy Tony's pump. There is a Big difference in over all quality and design the Sherwoods will Never be reliable.