Fan Clutch and Crank pulley bolt, 1966, L79

[Rich G.]

Re: Fan Clutch and Crank pulley bolt, 1966, L79

David

Thank you for that info

Rich

[John H.]

Re: Fan Clutch and Crank pulley bolt, 1966, L79

John,

On UPC L79-A1 of both the 1966 and 1967 AIMs it shows GM #3815933 Bolt for the crankshaft pulley center bolt. This same bolt is also called out for the steering shock/damper bracket to relay rod fastener (UPC 9-A3, Item 10, 1966-67 AIMs).

On my '67 L79 (with steering shock damper, no power steering), I found the same bolt used in both locations, exactly as called out in the AIM. It is a regular hex, Grade 8 bolt with a "TR" headmark. For both locations, this bolt has a cross-drilled hole through the head of the bolt.

Are you saying the holes were not present in the bolt when it was manufactured, therefore the bolts must have been removed, drilled and the bolts reinstalled at a later time (e.g., by owners or mechanics, after the cars were built and sold)? Or do you mean that the bolts came to the factory with the cross-drilled hole, and you were only pointing out that a safety-wire was never used in production?

Scott -

The bolts were received from the supplier with the hole for the safety wire, but no safety wire was used in production.

[Scott S.]

Re: Fan Clutch and Crank pulley bolt, 1966, L79

Scott -

The bolts were received from the supplier with the hole for the safety wire, but no safety wire was used in production.

Thanks John.

[Joe L.]

Re: Fan Clutch and Crank pulley bolt, 1966, L79

Thanks John.

Scott------


These bolts were still available from GM until very recently, but they are now discontinued. The headmarking was, of course, not period-correct and the zinc plating was shinier than that used in the 60's, but the bolt was otherwise configuration-correct.