blown head gasket????

[nfamousplayer]

So after getting my mercruiser 470 to start I shut it off. I tweaked some things then went to start it again it ran smooth for about 15 seconds then a very light brown milky colored oil gurgled out Pf the oil vent that connects to the carb. I think it needs a new head gasket.... I may be wrong ... any different ideas of what it could be?


Josh

 

[Don S]

Re: blown head gasket????

That would have to be the worst head gasket leak known to man to get that much water in the oil in such a short time. But I guess it could be possible.
Beside, that would be antifreeze. Did you check the antifreeze level?
I would suggest you drain the antifreeze and pressure test the cooling system and see if it holds.

 

[nfamousplayer]

Re: blown head gasket????

I don't know if it would matter but I added about a quart of coolant to the cap not the into the cap not the reservoir... I had started the engine several times before this and I ran smooth... is it possible I over filled it? Also Idk if it would make a difference but that freeze plug was also removed at the time I started it... I really don't think with as smooth as the thing ran when it did it was smooth and powerful with great compression

 

[Don S]

Re: blown head gasket????

Even if you over filled the reservoir, it wouldn't go into your oil. And to fill the engine full of water enough to come out of the valve cover is going to take gallons of water, not a quart.
You have a big problem, not sure where it's at just yet.

 

[nfamousplayer]

Re: blown head gasket????

I also hooked a water hose up to the water pump inlet to see if it was getting flow could this ha e causes it?

 

[nfamousplayer]

Re: blown head gasket????

While the motor wasn't running

 

[Don S]

Re: blown head gasket????

I also hooked a water hose up to the water pump inlet to see if it was getting flow could this ha e causes it?

Nope, shouldn't do a thing. Water would not get past the impeller. Even if it did, it would go out the exhaust, not into the crankcase.

 

[nfamousplayer]

Re: blown head gasket????

Hmmm... I don't understand how it could run so smooth and then just foul up so quickly .... so drain and pressure test....