Water in 3 cylinders

[HAS]

MY 1985 5Ohp. 4cyl. Mercury stopped running after running more then an hour at about 1500rpm.
I tried to start it when I got home, it ran very bad for about 10 seconds, after that it would not start.
I removed the spark plugs, #1 plug looked ok, #2,3,and4 are clean as new. I replaced the
exhaust plate last November, is there something I might have missed?. I knew the pistons and
cylinder walls were scarred pretty bad and it would soon need to be overhauled, I started to take it
apart but don't have a clue what to look for. The cylinders will have to be bored for oversize pistons.
I appreciate and thank you for any and all help............HAS

 

[Chris1956]

Re: Water in 3 cylinders

Sounds like water intrusion. You replaced the exhaust baffle and it's gaskets? Did you look at the inner water jacket cover? That can leak as well.

 

[CharlieB]

Re: Water in 3 cylinders

While apart, check the exhaust cover for any warp, a flat file or piece of sand-paper on a piece of glass should show and warp which would contribute to poor sealing of the inner plate and gaskets.

 

[HAS]

Re: Water in 3 cylinders

Chris1956 & CharlieB
Thanks Guys I have started working on the exhaust cover, looks better already, might
be able to finish tomorrow............THANKS AGAIN ..........HAS