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Left engine cover leak (the one that contains the starter clutch)

Motorhead

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I'm pretty desperate at this point.
There's a little rubber insert to pass the pickups' wires through. This grommet forms a line with the cover's mating surface, against the engine case mating surface.

(It's not the three-bolt "points" cover)

So the cover's paper gasket always leaks from where it touches this grommet (sometimes from both faces of the gasket).

The grommet obviously doesn't sit as tight as it should against the engine case mating surface. Perhaps it shrank a bit.

I tried (always with the oem gasket) - victor reinz reinzosil (only over that point), Hondabond 4 - dressed the gasket from both sides - the latter held for about 600 mi. and eventually started leaking as before.

My last attempt was Hondabond 4 again but only at the grommet area, putting a little thicker layer at where it leaks, and the let it dry for 24 hours.

It didn't hold a day.

The surfaces and the gasket were always bone dry.

Should I try to seal it without the paper gasket at all, with Hondabond HT or Victor Reinz Reinzosil (like cases halves are)?

 
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I'm pretty desperate at this point.
There's a little rubber insert to pass the pickups' wires through. This grommet forms a line with the cover's mating surface, filling a dip in it.

(It's not the three-bolt "points" cover)

So the cover's paper gasket always leaks from where it touches this grommet.

I tried (always with the oem gasket) - victor reinz reinzosil (only over that point), Hondabond 4 - dressed the gasket from both sides - the latter held for about 600 mi. and eventually started leaking as before.

My last attempt was Hondabond 4 again but only at the grommet area, putting a little thicker layer at where it leaks, and the let it dry for 24 hours.

It didn't hold a day.

The surfaces and the gasket were always bone dry.

Should I try to seal it without the paper gasket at all, with Hondabond HT or Victor Reinz Reinzosil (like cases halves are)?
sorry, accidential self-reply.

 
The grommet is not bone dry, oil leaches out of it to ruin your seal. Consider as well that the pickup wires going through it may create a leak port as well.
 
The grommet is not bone dry, oil leaches out of it to ruin your seal. Consider as well that the pickup wires going through it may create a leak port as well.
It was bone dry when I applied Hondabond 4 to it and then let it sit for 24 hours before starting the engine. It supposed to be oil resistant once it's cured, isn't it?

Maybe Victor Reinz Reizosil could be better for this?
Or the blue polyurethane compound from the same maker?

With, or instead of the paper gasket?

I may be talking nonsense here, but I really have no clue at this point.

Just in case, here's a pic of the cover and the grommet in question (not actual mine, the pic's from eBay...)
bff55aed9c72ae51c8e2139c45e044bf.jpg


 
Rubber soaks up oil, you can degrease all you want and still have more exude out of the rubber when you squeeze it.

Look here, the grommet sealed originally by being crushed on all 4 sides, if it slips in and out of the notch in cover there then you can crush at the gasket face to seal all day long and still be leaking on the rounded side(s) that match the notch. Why I bring that up is that the pic seems to show frayed rubber at both ends of the notch outer corners, meaning the rubber piece is fragging out to be cracked or frayed inside at the rounding to leak no matter how tight you scrunch down on the gasket. Not yours but if the same way.........

If the individual wire coverings have delaminated from the rubber then each wire can be a leak source to at its' hole in the rubber.

If the rest of cover has no dents in it one could simply drop the gasket and using a good grade of gasket maker seal it with that alone, but will not likely stop the leak. You've lost as least some of the rubber compressibility, the rubber has a notch formed in it to lose squeeze there. Yours again may be same way. You could carefully cut a piece of gasket material or even thin metal exactly the same shape and size as that notch and say temp glue it to the rubber to make a stuffer to tighter push in on the rubber to seal better, that may work. The shape and size are critical to avoid a worse leak.

Or, the odd fix, find a rubber band thick enough to be as wide as the rubber groove and small enough in OD to be tight around the grommet to add that thickness to crush grommet more too.

More than one way to approach fixing that. The problem is not one of gasket goop, which immediately flexes/flows out of the way of crush when the part is installed, it is one of a substance/material staying exactly in place to force the existing rubber to be crushed more, gasket goop will not do that.
 
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Rubber soaks up oil, you can degrease all you want and still have more exude out of the rubber when you squeeze it.

Look here, the grommet sealed originally by being crushed on all 4 sides, if it slips in and out of the notch in cover there then you can crush at the gasket face to seal all day long and still be leaking on the rounded side(s) that match the notch. Why I bring that up is that the pic seems to show frayed rubber at both ends of the notch outer corners, meaning the rubber piece is fragging out to be cracked or frayed inside at the rounding to leak no matter how tight you scrunch down on the gasket. Not yours but if the same way.........

If the individual wire coverings have delaminated from the rubber then each wire can be a leak source to at its' hole in the rubber.

If the rest of cover has no dents in it one could simply drop the gasket and using a good grade of gasket maker seal it with that alone, but will not likely stop the leak. You've lost as least some of the rubber compressibility, the rubber has a notch formed in it to lose squeeze there. Yours again may be same way. You could carefully cut a piece of gasket material or even thin metal exactly the same shape and size as that notch and say temp glue it to the rubber to make a stuffer to tighter push in on the rubber to seal better, that may work. The shape and size are critical to avoid a worse leak.

Or, the odd fix, find a rubber band thick enough to be as wide as the rubber groove and small enough in OD to be tight around the grommet to add that thickness to crush grommet more too.

More than one way to approach fixing that. The problem is not one of gasket goop, which immediately flexes/flows out of the way of crush when the part is installed, it is one of a substance/material staying exactly in place to force the existing rubber to be crushed more, gasket goop will not do that.
Yep, my grommet is pretty much in the state of the one in the picture.

Let's consider the problem narrowed down to the grommet being compressed over time and now not providing the same tension of seal against the paper gasket/engine case mating surface.

It didn't look as if the oil was sipping through the wires, they seem well caked into the grommet.

However, the grommet's flat face (the one that goes against the gasket and the engine case mating surface behind it) doesn't sit tight against that line. When the cover is off, I can easily push it with my finger below the cover mating surface. I thought it wasn't that critical because there's no real oil pressure there (or so I thought).

But with what you said, I think I would partially fill the groove in the round part of the grommet with some RTV that would make the flat face stand out of the cover mating surface a bit and let it cure before installing the cover. Ideally, it will "prop" the grommet and push it harder against the case. The idea is to "add rubber" to the grommet where the rubber has shrunk with time.

I understand that in the latter scenario the RTV will not cure on the oil-soaked grommet completely, but since it will be held between the grooves (of the grommet), it will be less prone to wash away?

Same could be done with a very narrow piece of rubber, but that rubber would have to be correctly temperature-resistant...

By the way, Victor Reinz say their Reinzosil RTV could work even when applied without the parts disassembly - sounds weird but maybe good enough for filling that groove in the grommet.

 
Well, Looks like this specific problem is solved for now.
I "backed" the grommet with some Victor Reinz RTV from the cover side (the rounded side of the grommet) in a way that the grommet mating face was a bit above the cover edge. Then I let it dry completely before tightening the cover. So far, so good (at that specific location). Thanks amc49 for the help.
 
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