KZ750 Shaft stripped diff drain plug

Hello once again everyone.

I made a silly SILLY mistake while changing my rear differential oil. Without thinking I accidentally went right instead of left while removing the drain plug about a quarter of a turn. Everything seemed fine until I realized I pulled 1 thread out. I can still put the plug back but it doesn't get fully tight. It doesn't seem to be excessively loose though if that makes sense. It seems I am at a crossroads, I don't know if I should just leave it or what. I went for a 20 minute ride and it didn't leak. I've heard people reccomending teflon tape. I'm not sure if they sell oversize plugs that small. 

Thanks all

-KzJM

If it doesn't fully tighten it will come out with vibration whilst driving. Is there a heli-coil kit available for the thread size (what size thread is it)

If only a quarter turn stripped it it was probably over tightened to begin with. A Heli coil and new sealing washer, as suggested, would work.
 

If it won't be coming out very often maybe a little bit of blue Loctite? Would give some peace of mind that it won't vibrate loose and might help seal it.

Franklin wrote:

If it won't be coming out very often maybe a little bit of blue Loctite? Would give some peace of mind that it won't vibrate loose and might help seal it.

May work but for the sake of a couple of hours and a few bucks do you want to risk dumping hypoid gear oil all over your rear tyre !! 

I agree helicoil is a better long-term fix but if the threads are already holding enough that it doesn't leak then no way it falls out with Loctite on it. Drain plug isn't some high-torque application. Wouldn't worry me at all.

If you’re going to just loctite it, run a tap through it to clean the threads as they’ve been deformed. 

Would definitely recommend a heli coil or thread sert. Teflon tape might work for an extremely quick fix till you can get it fixed right. 

KZ750 rear differential ebay search today produced thirteen results...



 

Perhaps it may not be seen as the best way of repairing the issue, but I came up with a solution. I took a bolt that was slightly smaller than the original and put one of those vacuum caps on it. It was a very tight fit. I then proceeded to find the proper washer and rubber O-ring that matched the original washer. Have you ever seen a rubber fill plug on a Dana rear end? This was a similar idea. The rubber vacuum cap on the bolt fit very snugly inside of the stripped bolt hole, I covered it in RTV and used a rubber mallet to hammer it in. 1 day later I come back and it's solid as a rock. I can't get it to budge by hand. The RTV created a sealing surface between the washer and the bottom of the differential assembly as well as around the rubber vacuum cap that serves as a plug. I know you will all shake your heads at this but honestly it seems like it's holding well and I haven't noticed any signs of leakage.

A "win is a win" but to be honest doing the job properly would have been easier (which is often the case) but "your ride, your rules" 

You're right. I ended up doing a heli-coil because it didn't hold. Definitely a better idea