Oil filter drain bolt

Okay, I did a search and never got a definitive answer to the following question: Is the purpose of the little hole at the bottom of the oil filter housing to drain the oil from the housing? In other words, can I plug the hole? I am tired of the chewed up threads on the drain bolt caused by the metal flakes finding their way into the threads.



There was a tip from Ty Davis published in one of the mags, Dirt Rider probably (I read them all though). On his bikes he taps that hole and installs a plug.

I’ve always just blown this hole out with solvent or contact cleaner when doing oil changes, and I’ve never had any problems with my threads. Instead of laying the bike on its side before taking the filter out, which is in fact a good way to avoid messy cases, I lean it over the other way and support it with my shoulder while I remove the cover. This way everything drains out, and if you lean it over far enough (virtually) no oil ends up running down the cases.

I ended up stripping that hole. My torque wrench was misadjusted and I ended up putting too much torque on it. :) If I tap it will the flash get into the case? Also, how far in does the hole go? I don't want to damage anything inside.


Dan, I think (not sure) that the hole is only in the cover. You should be able to remove the cover and helicoil the hole without getting anything in the engine. I will look at my bike when I get home to see how far the hole is threaded. I'm sure someone else on this board knows the answer.

Hey Guys-

That screw hole is not blind. It opens to the case. You want to be very careful not to let the debris fall into the cases. The best way is to pull the whole right-side case cover off and fix it with a helicoil or timesert.


Dan, mine did the same thing. MXTuner inserted a tyme or timecert into the allenhead threads & it stops up the little drain hole. No problems with length. Metal particles will eventually destroy the threads. Keep an eye on the shape of the allenhead bolt for disfiguration. The timecert fixed the whole darn problem.

I put a heilicoil in mine with no problems. :)

Thank you. Next Question. What is a Timecert or helicoil? :)


Are the threads only in the right side cover? In other words, can the cover be removed and the threads repaired with a helicoil or do the threads extend into the engine?

Not sure what timecert is, Me thinks it is the same as a TimeShare that you can get with other people for a vacation rental or something

But a Helicoil is a nasty critter that lives in the desert I think Arizona. They say if you get bit by one it can kill ya


The threads only go through the case side

and not into the engine.

http://www.timesert.com/ Here is a link that describes what a timesert is better than I could spell it out here.

Good luck, take your time and follow the manual and you should be alright for the repair.


Originally posted by Dan Lawrence:

Thank you. Next Question. What is a Timecert or helicoil? :)

Don't know what a timecert is either. A Helicoil is a wire coil used to replace threads and comes in kit form, easily found at most fastener supply or even automotive stores like Pep Boys.

What you do is drill the hole out to a larger size, larger by the diameter of the helicoil wire I imagine, and tap this new, larger hole. Then you insert the coil, which threads itself into the hole. Now the coil itself acts as the new threads into the hole.

They work amazingly well, I've only used them a few times on bikes but probably 20 or 30 times on various ranch equipment I've managed to screw up, and I've yet to be disappointed.

Hope this helps.

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