Sealant or not?

[Mad Professor]

Very thin layer of sealant on both sides of a gasket. As mentioned ^^^^^, some gloves using the thumb and index finger to just get a thin film. Whatever used needs to be fuel resistant. I've used Permatex High tack/Aviation, various silicones. A brush can or big tube will last a long time (if you keep them sealed). For deletes something like Dirko or Yamabond.

Don't be a slob and slather on so much sealer it gushes out when the parts are assembled.

Getting both surfaces clean and flat/smooth should be first concern gaskets or not.

If the parts are all apart and can be cleaned, dressing the surfaces with a large flat stone will remove the last bits of old sealer or gasket materials. The stone will leave a slightly rough not smooth surface, that the gasket and/or sealer will adhere to. I did a lot of motorcycle case halves that way.

 

[Motorka]

Dirko and HYLOMAR M.

 

[lehman live edge slab]

Honda Bond HT.

I use it sparingly but everywhere. From the filter base to the cylinder base, not on the exhaust side. I don’t like problems, don’t mind wasting time avoiding wasting time.

The G366Pro didn’t seal the snorkel worth a *s-word. So I put *s-word there too. An O-ring, shouldn’t, shouldn’t have had to, but I wasn’t about to let it suck fines.

Had a 372 clamp fail on a saw I built. Never knew it until I went back in.
The Honda Bond did its job, had to work a second just to get the boot off.
Nothing wrong with a belt and suspenders

Seems that the issues the Stihl clones have with boot leaks aren’t because of the design they copied but the wrong rubber they make the boots out of. The aftermarket ones seem much harder and don’t seem to squeeze in to form a good seal.