1968 crankshaft pulley bolt sizes

[Gary68]

Putting engine pulleys on and 2groove pulley I have bolt holes don’t line up. Also seems balancer has 2 or 3 different size bolts 3/8 and 5/16 I think. Are crank pulleys all different. My engine block is 68 but crank maybe 71?

 

[Lefty71]

Balancers strip out the pulley holes very very easily. None of the original holes are for 3/8" thread.

 

[RemCharger]

Balancers strip out the pulley holes very very easily. None of the original holes are for 3/8" thread.

Agreed. Someone's done some home machining there. And the original bolts are somewhat special, with very small washers so they don't interfere with the balancer hub snout.

 

[pnora]

All should be 5/16 NC. There are balancers as well as the pulleys that have one off set hole. Easy enough to slightly elongate one hole so they will bolt up. I would rather heli coil the striped ones. You might be better off with a good balancer.

 

[lewtot184]

5/16-18 is factory pulley bolt size.