Valve Cover Gasket

G6 at Snook, TX · Jul 11, 2013

How unusual is it for a gasket to blow on a valve cover? I was mowing today and noticed some oil sheen and pooling in the crevices near the oil gauge line elbow and below. I am 95% certain it is not the elbow.

This is an 8n frontmount.

In the fix, does the manifold need to come off? It appears that it does not. Also, should I use some Ultra-Black on the gaskets?

The tractor is running fine otherwise, and I am not even sure it is worth my time to fool with as little oil is leaking.

JCinKY · Jul 11, 2013

Very unlikely to "blow" them out. You've probably just sprung a leak.

How old are the gaskets?

You do not necessarily need to remove the manifold to put new gaskets in, but it makes it a lot easier. DO NOT use any sealer, just the cork gaskets.

Don't over tighten them either or you will distort the cover. This is probably why yours are leaking. If over tightened the cover distorts and the gaskets no longer seal properly.

souNdguy · Jul 11, 2013

blow? unlikely.

unless you have tons of crankcase pressure.

got a plugged cap?

holed piston?

missing like crazy?

more likely the gasket is just umpettn decades old and leaky and gone.

with monkey hands you can pull it without removing much..

G6 at Snook, TX · Jul 11, 2013

The amount of oil leaking makes me think that the old gaskets just gave up.

Admittedly, this tractor was pushing 41 psi when I was running it at 3/4 or more throttle today in about 95* heat. Runs good at a high setting, though there was a bit of trash in the carburetor today (or the float stuck) as it started to miss on the side of a hill. It has a low idle irregular ping that I have given up chasing on a 6v frontmount with points.

I have a young man who works for me and has has longer and thinner fingers than I do and he can do the cover with the leak.

I was looking at the nut that holds the cover in place and it looks like it too has a rubber gasket below the washer; it was split, but no leakage. Is that necessary to replace or can I get by without it?

souNdguy · Jul 11, 2013

if you need a gasket under the nut it's easy to fake with a piece of innertube.. or heavy casket paper.. fiberboard.. etc...

Bob Harvey · Jul 11, 2013

Or an 'O' ring and washer.

souNdguy · Jul 11, 2013

yup.. many things...

Bob Semp · Jul 12, 2013

Are you sure it's the valve cover and not oil
leaking from the rear exhaust manifold port (I had
that with mine) ...

G6 at Snook, TX · Jul 12, 2013

(quoted from post at 13:00:22 07/12/13) Are you sure it's the valve cover and not oil
leaking from the rear exhaust manifold port (I had
that with mine) ...

The leak did not appear to be weeping from the fourth port. I don't think it is that high up and appeared to be from the cover area. I will double check to make sure.

JCinKY · Jul 12, 2013

(quoted from post at 06:17:44 07/12/13)

(quoted from post at 13:00:22 07/12/13) Are you sure it's the valve cover and not oil
leaking from the rear exhaust manifold port (I had
that with mine) ...

Click to expand...

The leak did not appear to be weeping from the fourth port. I don't think it is that high up and appeared to be from the cover area. I will double check to make sure.

My block has an oily sheen under the cover area all the time. Covers aren't in perfect shape.

I just wipe it off from time to time and live with it.

If it don't drip any oil, that means there aint none in it :lol: :lol:

G6 at Snook, TX · Jul 12, 2013

(quoted from post at 14:55:59 07/12/13)

(quoted from post at 06:17:44 07/12/13)

(quoted from post at 13:00:22 07/12/13) Are you sure it's the valve cover and not oil
leaking from the rear exhaust manifold port (I had
that with mine) ...

Click to expand...

The leak did not appear to be weeping from the fourth port. I don't think it is that high up and appeared to be from the cover area. I will double check to make sure.

Click to expand...

My block has an oily sheen under the cover area all the time. Covers aren't in perfect shape.

I just wipe it off from time to time and live with it.

If it don't drip any oil, that means there aint none in it :lol: :lol:

I have chased leaks on these old machines in the past that were, in reality, minor to a nuisance issue, and it has cost me a day or two in labor to achieve very little return. If it continues like it is, I will leave it, but if it becomes a cascade, then something would need to be done. These old machines leak--that is what they do.

G6 at Snook, TX · Sep 30, 2013

A few months ago I noticed an oil leak on my 8n front mount. Anyhow, I thought the issue was located at the brass oil terminal between gauge and filter on the block near the manifold. I replaced the brass and line. I evidently have a hairline crack that oozes oil behind brass terminal. It is not in the threading but near it.

To seal up the crack this side of welding the cast iron, what would be a good epoxy or goop to use? Ultrablack? JB weld?

Hobo,NC · Sep 30, 2013

Glue the gasket to the cover with 3M 8001 weather strip adhesive it will stay put...

They don't leak if you know how to seal them.....

I don't expect Y'all to know how to seal a engine with so many wanna be mechanics around that dream chit up that cost them nuttin and put a fancy word like case study on the only damm anything they have ever work on....

G6 at Snook, TX · Sep 30, 2013

It is at the brass oil terminal. Leaking behind it. It is not the cover.

Valve Cover Gasket

G6 at Snook, TX

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JCinKY

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souNdguy

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G6 at Snook, TX

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souNdguy

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Bob Harvey

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Bob Semp

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G6 at Snook, TX

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