Water in cyl #1

oldseaox

Seaman Apprentice
Joined
May 16, 2009
Messages
49
200 Merc, salt water eng. Started running rough at low rpm, will not reach normal wot. Pulled plugs and found traces of water in #1 and #3 cyls. Compresson test shows #1 65lbs and #3 105lbs, all others 105 to 110. Eng is approx 20 yrs old but has run well until now.
I am holding off any action until I get some objective feedback, any ideas and thoughts are welcome.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,074
Re: Water in cyl #1

OK, Sounds like a bad head gasket. You might get lucky and that will fix it....
 

tpenfield

Moderator
Staff member
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Jul 18, 2011
Messages
18,137
Re: Water in cyl #1

The numbers look low accross the board, but maybe you had the throttle closed or the battery was not up to full charge.

It could be a number of things . . . might be the exhaust manifold/elbow joint is failing causing water to get into the cylinders. It could be the head gasket as mentioned. If you want to isolate the problem more specifically before you start loosening bolts, then do a cylinder leak test and make note of where you are getting leakage.
 

oldseaox

Seaman Apprentice
Joined
May 16, 2009
Messages
49
Re: Water in cyl #1

Numbers are somewhat low but have been the same for the last three years or so, except for #1. Pulled the head and found a bad place in the gasket just below the thermostat. Two bolts broke on the inboard side of the head and left about one inch sticking out but they are side by side with 5/8" between them. Not much room to work. Can heat be used on this stuff, I don't have experience with alum.
 

MercMan82

Petty Officer 2nd Class
Joined
Sep 13, 2011
Messages
192
Re: Water in cyl #1

Yes heat is preferred. Just don't overheat. Heating and cooling works well with corrosion. Once heated, get some vise grips or something that will grab a good hold and try going loose then tight. Once you get play, even a little, it will come out with enough patience. Go slow. if it doesn't move, use PB blaster with heat. I also heard touching a candlestick to the heated bolt will suck the wax into the hole and lube it. Never tried it. Heating then cooling causes the bolt to expand and contract breaking the corrosion up enough for the bolt to be worked out in most cases.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,074
Re: Water in cyl #1

As MM said. Heat up the bolt studs and remove the heat and spray with PB Blaster and let it cool and suck the oil in. I would repeat the process at least once more before I try the vice grip.

I doub't the wax treatment will even work, as the wax has got to be too think to penetrate anything.
 
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