Bolts for mounting Starter Motor.

[LTGTR]

I recently purchased a second hand starter motor without mounting bolts.
One hole appears slightly larger than the other 3.
Parts diagrams show 2 different part numbers for the 4 bolts. It appears 2 of the bolts have no thread on the upper part of the bolts. Are they a special shouldered bolt for positioning purposes.
Can somebody tell me the difference please.
Thanks - Ray.

 

[Signal]

From memory the bolts are all the same size so you may have a stripped thread in the case. Looking a the parts diagram on CMSNL bolt #17 has a shoulder bolt #16 does not.
https://images.cmsnl.com/img/partsl...g-motorxs650dee006501f_bigyau0812c-7_be50.gif

 

[DogBunny]

It appears 2 of the bolts have no thread on the upper part of the bolts. Are they a special shouldered bolt for positioning purposes.

Your observation is correct. All four bolts are identical, except two have no threads on the upper part. I have no idea why. I never pay attention when I remove them, so I never know which go where. The parts diagram shows where one of each style bolt goes, but it doesn't show where the the other two go. I don't think it makes much difference.