stripped oil drain thread ... help!

hey guys today i took my lower oil drain bolt off to drain the oil, some threads came out with it!! and it wasn't from the bolt itself.....ugh which means some where along the line my threads inside became stripped. Has anyone had this happen to them? Ive always been careful with tighten my oil drain bolt using my torque wrench so i don't know why they are stripped now?? anyways what is the best fix I have a race on sunday!!! re tap or can a coil be put inside??

I had no luck with a helicoil. Maybe I didn't get enough pooky and the insert itself but it always leaked. What I ended up doing was packing the hole full of grease, drilling it to a 1/2 hole (I think), and inserting a self tapping pigy back drain plug. Once the main plug is in, all you have to do is remove the smaller plug in the center and you won't wear out the case. Do this at your own risk, there is a possibilty of getting metal in the crank case , that's why I put the grease there. It worked for me anyhow. If you do this, make sure to drill the littler plug for safety wire and wire it up each time you change the oil.

Generally retapping to a larger thread diam. is stronger, but I'd try helicoil first

I had the same thing happen to me. I'll second the retapping and going the next size up drain plug. Haven't had a problem

This is the fix:


Mine stripped too. At first I just extended and tapped the hole about 5 threads and used a longer bolt, but it didn't last long. So, I bought a helicoil kit, placed the original bolt through the filter cover and measured the remainder of the bolt. Then I put tape around the drill bit to the same length as the above measurment so I don't drill too far. I used strong thread lock (I let it dry before putting the bolt in) on two small helicoils (to get the desired lengh, but some helicoils are longer) to make sure they don't try to come out, or should I say in. Works great, it holds torque specs, it's all good.

I stripped mine out

I went and got a Heli-Coil Kit for a 12mm 70pitch

It worked but you need to make sure you get this Thread started Straight and use Axle grease to keep the chips from going into the engine.


Keep backing it out to wipe the chips off and regrease

Bad part is I just snapped the head of my bolt off tonight :)

I was able to easy out the broken piece

I gotta side with grey on this one . Speaking from experience, i helped a buddy with his 2smoke. Same thing TIME SERT Worked as advertised and when finished uses the OEM drain plug.

thank you very much for all your advice............i took it over to my local shop........I didn't want to try this myself .........what they did was a "Time Sert" .........they charged me 1hour labor, but at least I know it was done properly(i hope)...

i'll update on how well it holds up.........

I just fixed mine last weekend. I'm sorry to hear that it happened to you, but it makes me feel better because I'm not alone. I freaked when I did it. I'm always so careful and just couldn't believe that it happened.

The fix was pretty easy for a novice machinist. I bought a helicoil kit from I think that you'll need a M14 X 1.5. My 426F is a 2001, so I needed a M12 x 1.5. I also bought a new magnetic tip plug from Zip It won't help with the crank case chips because they aren't magnetic, but it does pick up a lot of other stuff.

Some tips that I would suggest for putting it in.

- Play with the Helicoil tool if you haven't ever used one before. It's not hard to use, but you don't want to be trying to figure it out when your under the bike and have oil running down you arm.

- Practice breaking off the tang on one of the helicoils that you get in the kit to see how it snaps off (it will be inside the engine when you finish installing it so you want to make sure that you know how to remove it from the bottom side before you screw it up in there.

- Make sure that you use the right drill size. Mark your depth with tape and don't get too excited.

- Make sure the tap is straight.

- Take your time.

- Make sure that no-one can bother you when you're doing it. You're performing surgery on your baby and disruptions don't help.

- Absolutely make sure that you have the tang in your hand when you are done. It snaps off pretty easy with some needle nose pliers, but it will want to fly up into the engine if you don't get a good grip on it.

- And again, take your time

All-in-All I was surprised that it was that easy. It worked like a charm and only cost about $75 for both the kit and the plug.

Not sure if you'll get going this weekend, but you'll be back on the road (or dirt) soon.

This might be a good thread for this question?

What are some good tool companies to order these materials from, for those of us in the hinterlands and where can you buy a 1/4 inch torque wrench?

This might be a good thread for this question?

What are some good tool companies to order these materials from, for those of us in the hinterlands and where can you buy a 1/4 inch torque wrench?

Most good auto parts stores carry Heli-Coil kits. Most also have a line of tools that includes torque wrenches, and of course, there's Sears. Craftsman stuff is plenty good enough for most home shops, and it's a good buy. If you have to go cheap, there's Harbor Freight. :holdnose:

A flex beam type wrench is less expensive and fits in around the cam caps without an adapter. "Clickers" are faster. Both types are subject to inaccuracy if used incorrectly.

Time-Sert lists some distributors on this page:

The great thing about a Time-Sert for drain plug repair is that it eliminates the concern about drilling or tapping the repaired hole out of square with the surface the drain plug washer has to seal to. See:

If you happen to skew the hole a bit, the spot facing tool used to counterbore the drilled hole corrects it, and the plug seals perfectly. Plus, there is no drive tang to snap off and loose somewhere you don't want it to be. :)

You must have a air compressor but ....... A little trick I have done to keep the chips from going into the motor is take a air blower and using elect tape around the trigger so it just blows a little and inset it into the crank case vent hose so it is blowing a small amount of air into the engine just a tiny bit and coming out the hole you are drilling or tapping. Use safety glasses since it blows all the chips/shavings out at you.

What size timesert kit should I need to fix this problem and still be able to retain my existing drain plug bolt?

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