sail drive raw water strainers

[schoonerdog]

I have a boat with two yanmar saildrives. I pulled off the raw water heat exchanger manifold last year and found that small bits of plastic bags had been suck up the small inlets and then balloned out in the manifold, along with bits of old impellers and barnacles. Most of the manifold intakes were covered and this was the problem of hoses blowing off because of back pressure, engines overheating, and the muffler burning through. I heard though that Yanmar does not recommend raw water strainers on diesels with sail drives. Was wondering if then I should substitute taking off the manifold once a year (I assume the manifold had never been cleaned before for a 7 year old boat) and cleaning it or putting on raw water filters. My engine compartment is cramped as is.

Any diesel mechanics out there know if its true that SDs really don't need a raw water strainer? Finally, the mechanic really took off the manifold and checked it. Anything I should watch out for when I do this myself?

[delmarrey]

Now that you have found all this stuff in your heat exchanger I'd recommend installing strainers anyway, wheather or not they're recommended. If they're down to the 4 oz. size they could be mounted most anywhere and EZ'ly checked and cleaned.

I check my strainer every morning when out gunkholing and usually have to empty it every other day. Mostly seagrass and small fishes in my area.

You must do a lot of motoring in Port areas. But I am surprised that you got so much stuff with saildrives. You must pick this stuff up in a dirty marina somewhere. The inlet's are well below the waterline, which is where most off the trash comes from.

[TaoJones]

Originally Posted by Sunspot Baby

I have Volvo sail drives and had frequent over heating problems. I installed new through hulls with sea strainers and quit trying to get cooling water through the sail drive. All my problems went away.

FWIW, I'm told that the sail drive is exactly the same unit as used by Yanmar so this is probably not just a Volvo issue.

George

. . . I kept it in mind for myself, because it seems so logical. Perhaps this could apply to your situation. If you would like to read the other thread, it can be found at: http://www.cruisersforum.com/forums/...rive-7587.html

TaoJones