Gary Blake wrote,
> I am trying to remove and replace the gearbox input shaft needle roller
> force fit bearing (part # 118507) on my Spitfire Mk3 gearbox (same as
> earlier Spitfires and Heralds). I have succeeded in removing the inner part
> and the needle rollers but am left with the outer casing of the bearing
> still inside the input shaft and I can't get it out.
> How best can I remove this outer bearing casing without damaging the shaft?
It's a severe press fit. Later on they switched to a loose fitting
bearing that rolled on both surfaces. One option would be to machine the
hole in the constant pinion shaft to accept one of those (ANYBODY: is
there anything functionally wrong with this idea?)
Other than that, sit in front of the TV with the shaft and a small file,
and work on cutting a groove. No need to worry about small nicks in the
shaft, but deep gouges might be bad.
Finally, when I was up against this same problem, someone suggested arc
welding a length of welding rod to the stuck race. They said the heat is
concentrated on the race and helps break it loose, the duration is short
so no damage occurs to the shaft, and you end up with a nifty little
handle to pull the thing out. I cannot in good conscience recommend
this, and I didn't do this myself (ended up with an NOS shaft), and I
will not be liable if you try this and your shaft winds up trashed! Has
anybody succeeded with this, besides the person who recommended it to
me??
Bill Kelly
'62 Herald
'68 Tr250
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