Final Housing Sealant ?

[JimInOz]

Machine is a small Komatsu dozer.
Just wondered what sealant to use on a new Final Drive Housing gasket? It's a large,thick gasket,so I assume a special sealant is required.

Thanks...
 

[Welding man]

If it is a thick gasket,why would you think it would take a special sealer. If it has a gasket I would glue it to one side or the other with weatherstrip adhesive and bolt it up and torque the bolts to the proper torque,If it had no gasket at all I would use anerobic sealer.
 

[AJ.]

Just looked at the on-line parts catalogue for a few small dozers, D20, 21 ect, the gasket is shown on its own with no mention of any sealant, a smear of clean light grease to hold it in place is all that's needed, I also noticed the price $86 for one,what a rip off.
Good luck
AJ
 

[NCWayne]

Most gaskets, by design, aren't supposed to require any help to seal, so no sealant is recommended. That said "design" and real life take different paths waaaaayt too often and no extra sealer means leaks. That said, what I always use is Permatex Ultra Blue or Ultra Copper (for higher temp areas). Unlike regular silicone, which some love to over apply, you can use your finger to smear a really thin coat on the housing (or gasket) and when you bolt it togther it doesn't squeeze out into big gobs like the regular stuff does. Over the years I've been back into machines I've repaired bfore, to fix something else, and have yet to see one of the joints I made up like this leak or cause any problems with the operation of the machine. I can't say as much for the ones where someone in the past gobbed silicone on and tightened everything up. In those cases I've seen everything from turbos going out from oil starvation because the supply side was nearly plugged, to engines shutting down from silicine slug that were squeezed through bolt holes getting sucket into a fuel line, and quite a few things in between.

As far as the recommendation to use weatherstripping cement, prepare to hear the next guy into the machine CUSS you and your ancestors both past and future if you do that......I've done it to others kith and kin so I speak from experience there.....LOL. The only time I would recommend that is in an extreem situation where nothing else has worked, and, bad as I hate to say it on just about any oil pan or valve cover gasket made out of natural cork. In the case of the cork using it will cause the next guy to cuss you when he has to clean it off, and not using it will get you cussed by the owner when it starts to leak in a month after the cork 'takes a set' and the bolts get loose. In the end all I can say is whatever your choice, good luck.
 

[JimInOz]

Thanks for the advice.I have several shop manuals from various machines,but none specify a sealant type.NC Wayne,I know what you mean about excess sealant...some guys just pour it in & when you're the guy cleaning it up,it's a time consuming PITA.I'll go with the Permatex Blue,as I have a Permatex sealant on my shelf & it's been very reliable.I want to get this fix correct ,as once is enough.
The first quote on the gasket was well over $150 bucks...second quote ,two months later ,from same Komatsu dealer was $95.