Hello all,
I've been presented with a problem,
the key way in a Subaru crank has become slightly wallered out. I was thinking of over sizing it to the next available size key stock, but cut it for a straight key as apposed to a half moon key and just cut the key way to the end of the shaft.
Then machine the exposed half of the key to except the stock pulley assembly.
I hope I made since.
any and all input welcome.
Jerry.
Sounds possible to me anyway.
won't be the first time it's been done
(11-26-2012, 05:34 PM)dallen Wrote: [ -> ]won't be the first time it's been done
Most modern engines have no key way in the crank for the bottom pulley
This is so you can get the valve timing spot on (timing belt)
Once the bolt is tight nothing will move
John
Should work. You can buy stepped key stock for that purpose. Machine the new keyway then cut the top of the key down before you install it.
Beware, there is a reason they use woodruff keys. Normal key ways, weakens the shaft.
Thanks all for your input I do appreciate the input!!
So Noitoen,
I understand what your saying but given the circumstance I'm not to worried about that, as you can see the key way starts about 4.09mm back from the end of the shaft and only makes contact with ruffly 1/2 of the balancer / pulley key way causing a slight twist to the load on the key thus the divot in the key way.
If I cut the key way on the shaft to the end of the shaft the key and both key ways shaft and pulley will have 100% contact making for a much more even load on the key and should eliminate the pulleys desire to spin on the shaft or at least greatly reduce it. Thoughts any one ?
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Jerry.
Once the pulley is tightened on to the shaft the key is doing nothing
Most modern engines have no key in the lower timing belt pulley (so you can get the valve / pump timing perfect)
I remember years ago having a box full of offset keys for setting cam timing (happy days)
I know you don't want to shear one on a full blown alcohol motor at about 15 grand, makes getting the pulley off a bit of a pain.
