Have a look at this thread (no pun intended) - http://www.lfgss.com/thread13710.html
I've used these before - Recoil thread repair kits
However it may be as simple as running a tap through the crank to clean up the thread. Can you try fitting the new pedal from the other side of the crank, that may have the same effect in cleaning the thread.
@wvm started
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Have a look at this thread (no pun intended) - http://www.lfgss.com/thread13710.html
I've used these before - Recoil thread repair kits
However it may be as simple as running a tap through the crank to clean up the thread. Can you try fitting the new pedal from the other side of the crank, that may have the same effect in cleaning the thread.