Stripped crank case cover plug

[Wobbly]

Ok, I'm getting a bit frustrated now .... previous owner / factory seems to have installed the threaded plug that goes on the left hand crankcase cover (that allows access to the crank to turn it over by hand) with about a zillion foot pound of torque. The plug itself has a 10mm hex slot cast into it which was a bit rounded out before and which is now very rounded out thanks to some bright spark and his rattle gun (ie. me) :roll:

The plug seems to be made out of some sort of cheese because it stripped itself out in 2 seconds flat with the rattle gun. I'm trying with a cold chisel to get some purchase on the side and tap it around, but it seems more inclined just to gouge chunks out of the soft metal than actually move it :shock:

Anyone got any bright ideas on how to get this sucker out? I'm not sure exactly what its made of, but I think alluminium based on its softness (don't think magnesium). I'm wondering if a bit of heat on it might help some? Worst case scenario would be having to remove the case cover alltogether and then do something like weld a bit of bent rod into the plug and use that with a breaker or something? :?

[Flash]

A good solid bang with a hammer can help loosen it (probebly not advisable on this though) try tightening it then loosening it. Heat might help, you'd want to remove it though.

[dicky]

I don't think heat will be of much use.
The plug is probably softer than the case and will expand quicker, making it even harder to remove.

I've had to do this before...

Smash it out with the cold chisel until you can pull bits of it out with vise grips.
Then just yank bits of it off the thread.
Cover the hole with tape when your finished and ride down to the dealer to get a new plug.

dicky
<yamaha's are soft>

[Wobbly]

:shock: yikes! I'd have to pull the magneto cover off entirely then to avoid getting bits of plug inside the cases. How about the welding idea? Probably too much trouble given that its aluminium though :-k

Bloody thing :Hangman:

[Trubritbiker]

I am assuming that the allen key hex is now roundish, could you try bashing in some hex or square bar into the hole thus making a new profile to try and twist it. Also with the shock against the thread it may deform the thread enough to release it. As Dicky said if they are both similar materials heating it will not have much effect.

[Wobbly]

Allrighty, got it out ... there was a bit more metal in the plug than I thought so I sharpened up the 'ol cold chissel, dug it in some more and eventually got it to move with a bit of hammering around its radius. It's thankfully in the bin now and the new one is on nicely now :up:

I also took the time to round off the back of my shifter, then replaced my countershaft sprocket oil seal and replaced the stock bushing with a u-beaut stainless one I picked up on ebay. Oil change this weekend and might even check my valve clearances. What a flurry of activity!! :lol: