One Cooling Water Intake - Two Engines

[cchesley]

I recently installed my 1 cyl diesel generator in the stb engine room of my catamaran. It now needs cooling water. A new through hull requires a haulout of course. But my 30 hp Yanmar saildrive intakes water through the saildrive to a strainer and water pump.

1) Can I tee off this source for water supply to my generator?
2) Do I need an isolating valve also?
3) Would running both simultaneously on the same intake be possible?

I don't really want to have to switch valves to do this since sooner or later I'll forget and try to run one or the other after 'forgetting' which one I used last. An electrical cutout is possible but much more complicated than I'd prefer and still wouldn't eliminate the need to go climb back down into my engine space each time I wanted to switch over.

The easiest solution is another throughhull but that means hauling and it's not really necessary yet.

[capngeo]

If the GPM flow through the saildrive is adequate than sure.... BUT, I'd bet the engineer who designed the saildrive didn't add volume for the "what if" scenario.

[gjberta]

Sharing of seawater coolant intake is never recommended and as surveyors, we would consider it a substandard installation. Remember there is no free lunch / do it right or don't do it at all.
The only seaconnections that can be shared (without a seachest) are those exiting overboard, such as cockpit drains, scuppers, etc....

If the hull is solid single series laminate (not cored) and hauling is not an option, it can be done with divers afloat.

If the hull is cored, you need to haul and remember, you need to relieve the core and build it up to solid laminate where your fitting goes through.