Water in Mercruiser Engine.?

Question

I have a 1985 Mercruiser V6, 205, 262 CID that has water in the middle cylinders. Port and Starboard. the other cylinders are dry.

The boat was winterized last fall and has sat since. I suspected head gaskets. I removed heads and the gaskets looked fine.

Any Thoughts?

Answer 1

take both risers off and clean the gasket material off real good you will find the mating surfaces on the riser and the manifold probably corroded away in the water passage slots that surround the exhaust port. If this is the case you will need new risers and manifolds. If you decide to go aftermarket instead of mercruiser use Barr Marine Manifolds . The other major aftemarket company id OSCO thet are junk and wont last as long

Answer 2

all mercruiser are required to get new risers as part of the suggested maintenance. saltwater rust the manifold and water is sucked in the valves. you have a major problem that will require a rebuilt engine. about $8 to 10,000.

Answer 3

looks and leaks are two different things, but it's probably a cracked engine.  get another motor and don't waste your time messing with it. you can make a career out of fooling with that thing. look for a deal, save up, or move on and don't worry about it for a while. own the boat, don't let the boat own you.

Answer 4

Check Intake manifold  for cracks