Methods to reduce water sitting in exhaust and preventing hydrolocking

[hzcruiser]

Originally Posted by peter loveridge

my engine is low in the boat and there is no room for the minimum clearances on the usual diagrams. I just shut the seawater intake off two minutes before the engine shuts down. This clears the exhaust system of water, and I have a flapper valve on the stern

And your impeller is still in one piece?

[peter loveridge]

yes, I use the blue ones that are supposed to be able to run dry for 15 minutes. When you shut the seacock some water at least remains. I change them every two years or 200 hours, but they are always all right

[daletournier]

Originally Posted by peter loveridge

yes, I use the blue ones that are supposed to be able to run dry for 15 minutes. When you shut the seacock some water at least remains. I change them every two years or 200 hours, but they are always all right

I think this is a bad practice. Yes they can be run try in the event of an accident occuring but I dont believe the manufacturer intended them to be run dry regularly and deliberately. Bits of impeller caught further down the line becomes more work.

[Q Xopa]

Originally Posted by Lepke

I have valves on my water mufflers that open when the pressure of the exhaust is gone as the engine is shut down. That way the engine starts with low back pressure, handy with an older engine. Also you can crank for awhile without worrying about water building and flowing into the engine. Since the engine is stopped, the muffler drain is open.
I don't like turbo engines, and if I have the hp I need available in a natural, I go that way. But I've owned many turbos and ran many others. I solve the problem of early turbo failure by replacing the turbo bearings and seals at about half life. A lot cheaper than a new/rebuilt turbo and easy to do. Also clean oil. Turbo bearings either get their lube oil thru a small passage in the head or an outside tube. The oil cools the bearings. Dirty oil leaves deposits restricting the flow. If the flow is reduced too much the bearings get too hot, degrade over time and enough heat will ruin the seals.
I just rebuild my Ford PU turbo for about $100.

Sounds good. Can you give us some details on your valves that open when the pressue of the exhaust is gone?