Water in cylinders and no compression
 

I just had a water leak in my boat which took on a lot of water and flooded the engine. After pumping the water out of the boat, I had the engine pumped and electrics and carb replaced. All looked good. When attempting to start the engine, there was again water in the cylinders. Also, there now apprears to be no compression in cylinders 2 and 4. I assume the water was sucked in through the raw water intake and through the exhaust. The engine is fresh water cooled, so if it was a head gasket or water jacket - problems I've seen in other threads - I would expect antifeeze in the cylinders not water. Is there ay other possible source or way water would get into the cylinders in a fwc engine?

Seems to me that the water would have to be entering from the exhaust, backfilling into the cylinders. Were you cranking a lot with the raw water intake open?

Ouch!
 

gregt, check the antisiphon valve if you have one. They can stick closed and water can "syphon" back through the exhaust.

Worth a check.
Dave Neptune:cool:

The engine was cranked a lot. Also no anti-siphon valve. The boat has the original copper water jacket exhaust.

I sounds like the only place the water could enter was through the exhaust as I suspected.

Thanks

I have that kind of exhaust too. Mine is Stainless—just painted copper. I've read that when they fail you have no warning and the water just comes in through a hole or crack from the jacket to the exhaust.

Mine exits the boat high above the waterline and no siphon is involved from the exit end. If you close the seacock then no seawater can come in.
I think you have it figured already:cool:
Russ