crank bolt size on a sbc

[chevyridinhigh79]

does anyone off hand know the size of the crank bolt on a sbc? i think its 1 1/8 or 1 1/4 but i can't remember.

 

[cyclone]

The thread size of the bolt that holds on the balencer is 7/16 fine thread.

 

[onetonbb74]

5/8 head on that bolt. If your turning the motor over by hand and your afraid its going to strip like i was, just get the bolt on kit that uses the crank pulley's 3 bolts and helps you turn the motor over without using that patheticly small bolt on the crank. Seen them at auto parts stores before.

 

[4X4HIGH]

SBC balancer bolt is 7/16"-20 x 2.25"/2.50" long

 

[chevyridinhigh79]

i wanted to get a breaker bar and a socket so i could spin the motor by hand to test and see if my timing chain is stretched.

 

[4X4HIGH]

I would not suggest using the bolt to turn the engine unless it is a quality ARP fastener.

 

[chevyridinhigh79]

its probably not. the kid that built it was a slacker and if he didn't already have the part there wasn't much chance he was going to buy it. call it a budget build or just being lazy, but if he would have actually taken time and spent some money he could have had a way nicer truck