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Stripped crank case drain bolt threads!

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2007 kawasaki 250f

So this is the second time that i have stripped out the threads.

The first time i drilled it to a 12mm and used a yamaha bolt.

Now ive stripped it again. Brought it down to the shop and they told me that i can throw in a 14mm but it may happen again very easily. Is it possible for me to still time-sert or helicoil it?

Another idea i came up with is close that hole and possibly drain oil either with a new hole or through the top?

I do not want to take apart the engine at all. I cant afford to fully fix it untill a month or 2

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First off you need a torque wrench, but if I were in you situation, I would take the bike to a very reputable welder and have him weld the hole shut, then grind it down nicely and redrill and tap for a stock sized drain plug, I myself wouldnt mess with a heli coil or timesert

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Is it possible to weld the hole shut with out an engine pull

you will likely end up with a leak between the case halves due to warpage. i have seen that happen before.

btw i am a fabricator and weld aluminum 40 hours a week...

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you will likely end up with a leak between the case halves due to warpage. i have seen that happen before.

btw i am a fabricator and weld aluminum 40 hours a week...

What do you suggest i do?

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you can tap it up again. do not try to weld on it on the bike....aluminum and oil/dirt won't fly....it has to be clean and you are only gonna get one chance to do it right. I have seen some expanding rubber plugs used in bobcats for drain plugs, but really if you are careful it should not be a problem. you can still heli or time it too. I would try it one more time and quit putting the plug in with an impact.

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if it was my bike i would put the stripped plug back in, and then cover the whole area with jb weld to seal it off, then just drain the oil through the clutch cover like you were saying. that would hold you over until you can replace the damaged case half.

another problem you will have is that the porous cast aluminum has absorbed oil and that will make it very difficult to weld.

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What cons would come from this other than a hassle to change my oil. Possibly a mess

Orings?

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You should be able to install a timesert in the hole, a timesert is superior to a heli-coil.

I have never used a torque wrench to tighten a drain plug and I have never stripped one out.

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