Exaust question

[DamnitBadger]

1978 260 Mercruiser. While trying to find why my oil had water in it I found the source to be water passing by the exaust plate that is between two gaskets where the elbow meets the manifold. I noticed there were black water marks on the inside of the plate between the water jacket and the exaust (there is a good 1/4' of material here and little if any corrosion). I have purchased new gaskets and plates but was told by the parts guy not to use any kind of sealant, just tork it down. Seems to me that this would be an ideal place for a hard setting permatex gasket sealant. What do the pros do? I'm replacing the studs as well as sanding the mating surfaces.

 

[KaGee]

Re: Exaust question

I have read numerous posts here that the new Merc gaskets use NO sealant. Your parts guy is correct.

 

[Laddies]

Re: Exaust question

It's better to true gasket surfaces with a good file, it will help keep them level--Bob

 

[Don S]

Re: Exaust question

The newer gaskets for the center rise manifolds and risers do not use any sealer on the new style gaskets.<br />Are the gaskets that you have for your style manifolds (see picture) coated with a gray graphite coating? If so, then they do not use sealer. If they are just paper gaskets about 1/16" thick, then some Mercruiser Perfect seal couldn't hurt.<br /><br />

 

[flashback]

Re: Exaust question

Just a question, how would he get water in the oil if the water were getting into the exhaust manifold, I would think that would cause hydroloc. not water in the sump, my guess is a freeze crack somewhere...IMHO

 

[Don S]

Re: Exaust question

If the water sits on the piston long enough it will leak into the pan past the rings. At least that is the assumption. Personally when I see engines damaged by water in the cylinders, the engine is usually locked up and the cylinder is rusted beyond recognition. (Salt Water is Wonderful Stuff) and the salt water can't get past the rust it caused to get into the oil.

 

[road_ragenj]

Re: Exaust question

i am having the same problem and have the same manifold as in the picture. my manifold is obviously cracked, i dont understand how the oil can mix with water. why doesnt the exhaust gas push it out. my engine runs great, except for the oil mixing with water

 

[f_inscreenname]

Re: Exaust question

"why doesn't the exhaust gas push it out."<br />If you kept your motor running all the time a small leak may not do it but you can not keep it running all the time. When you turn it off that is when it will leak into the cylinders. If it is a bad enough leak, when the motors pistons are on the exhaust stroke they will suck the water into the motor. Either way a bad manifold will get water in your motor and will soon kill it.

 

[peacekeeper6]

Re: Exaust question

i think i may be having this problem also but i dont know because i dontknow what to look for. i know i have water in my oil but i just replaced the head gasket so i dont know what to do, if u want to look at http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=24;t=011000 and help me out it would be apprecitated