Replace Paper Gasket With Chemical Gasket?

[garicao]

Hi...anyone have success using chemical gasket (hylomar, silicone, permatex-2, various loctites, yamabond, etc.) instead of paper gasket for low pressure (but oily) applications like alternator covers?

If so, what worked? Or, what didn't?

Thanx.

--garicao

"We're lost, but we're making good time."

[Steve]

Have we tried them? Yes.

Was there success? Usually NO. :shock:

Too many of those chemicals do not stand up to constant exposure to heat and/or oil, and the little bits along the edges will flake off. When they flake off, they get washed down into the oil pan. Depending on how big the flake is, it might make it through the pick-up screen, then get pumped into some of the tiny oil passages. If it were my bike, I would be lucky enough for it to block the most important small oil passage, therefore ruining the engine.

Paper gaskets are not that expensive, may as well use the right thing.


.

[Nessism]

With silicone you risk having a chunk breaking loose and plugging up an oil passage somewhere. If you must go that way, use the type of silicone that is intended to replace gaskets, not just supplement them - less chance of a chunk coming loose.

As a side note, rebuilt a Mazda rotary engine once and it used silicone on several joints to seal - such as the oil pan. I know Nissan does that as well in several places on their engines. The key is proper application and the proper material - you don't want strips of the ozzed out material to break loose.

Good luck.

[p_s]

The stator cover (at least on the '85 GS550) is unfortunately not low pressure. Part of the cover seals a pressurized oil line from the oil pump. It will leak unless everything is perfect. It took me probably 8 tries to get it to seal because I didn't take it seriously and I've never had a gasket give me any trouble before. (Well, except for the time I didn't seat the rubber valve cover gasket properly but that is a different story.) Go over every bit of the mating surfaces very carefully looking for high spots--basically anywhere someone used a screwdriver or wrench as leverage to get the cover off. Get every last bit of the original gasket off. I doubt you could get it to seal without a paper gasket in there.

[TheCafeKid]

Have we tried them? Yes.

Was there success? Usually NO. :shock:

Too many of those chemicals do not stand up to constant exposure to heat and/or oil, and the little bits along the edges will flake off. When they flake off, they get washed down into the oil pan. Depending on how big the flake is, it might make it through the pick-up screen, then get pumped into some of the tiny oil passages. If it were my bike, I would be lucky enough for it to block the most important small oil passage, therefore ruining the engine.

Paper gaskets are not that expensive, may as well use the right thing.


.

I might add to this, we're talking TINY TINY is all it takes. I have a 16V 750 motor in the basement ive slowly been poking around in, looking for the cause of the exaust side cams not getting oil and cooking, i have yet to find anything. The motor found it in short order, apparently.