Leaking oil

[1979 Quartermasters]

A couple of weeks ago I over heated my 1979, 140 horse Mercruiser at an idle due to a bad impeller. I replaced the impeller and played with the boat a couple of times. Last time out I discoverd the oil was down and began to look for why. I noticed some trails of oil running down the side of the block on the manifold side. This engine has the intake and the exaust all in one. I don't think the oil can get past the manifold from the rocker cover. I am thinking that it might be a head gasket. The oil is clean, no sign of water and the spark plugs are also clean. The oil loss is not huge, but I am wondering if I can run it like this for the rest of the season or am I risking a hydro-lock due to a bad head gasket. This is a great site and you guys have already been a great help just from reading. Thanks!

 

[totx]

Re: Leaking oil

Last time out I discoverd the oil was down and began to look for why. I noticed some trails of oil running down the side of the block on the manifold side.

Oil down on the dipstick? How much?

Can't see how you should get oil leak on that side of the engine from a blown head gasket.

Oil is pumped up to the cyl head in the push rods, and drain down in some holes.
But, that all on the other side of the engine.

Clean it all up, the bilge to.

Then it's easier to locate the leak!

 

[1979 Quartermasters]

Re: Leaking oil

The leak seams to be coming from behind the manifold. I am about to remove the manifol to see more

 

[1979 Quartermasters]

Re: Leaking oil

Turns out it was a leaky valve cover gasket. Thanks for your help.