Tim , got your message and called you back, do you have any motor shims PN# 606-305 ? Also just to make sure, you (with everything lightly tightened, you leveled your frame to make sure it's square??) center your motor using the shims, 1 per side between the motor and motor mount, and keep you clutch/startshaft stack barely snug, you want to make sure there is absolutely NO drag when you spin it with your fingers as it rotates in the "engine clutch/fan assy. Also making sure the cutch is ressesed in the clutch bell. Look at the manual for a visual reference. Any drag on this will certainly fail the startshaft. Once you have achieved the fit your looking for, snug in multiple increments one bolt on one side, the other bolt on the opposite side. This will help ensure a even tightening sequence. After every time you snug it up to achieve final torque make sure you spin the start shaft with your finger to make sure it still rotates smoothly. I have seen this happen and its happen to me where all is good and suddenly the shaft has drag.
You may already know all this, I certainly don't want to discredit your ability by any means, I'm very descriptive when explaining things, you extract what info pertains and pass on the other, when we help guys we cover everything in detail with the intention to help others also. Call me tomorrow afternoon. We can discuss further..
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