CRG Discussion Forum

Camaro Research Group Discussion => Originality => Topic started by: sixt9x33rs on November 08, 2011, 02:17:21 PM

Title: Exhasut Manifold bolt washers
Post by: sixt9x33rs on November 08, 2011, 02:17:21 PM

Why do some of the bolts for Small blocks have lock washers and others have rather fat flat washers?

Thanks

Lawrence

Title: Re: Exhasut Manifold bolt washers
Post by: firstgenaddict on November 08, 2011, 02:58:39 PM

Lock washers will not retain their "lock" with the heat cycling on exhaust manifolds.

Title: Re: Exhasut Manifold bolt washers
Post by: sixt9x33rs on November 08, 2011, 04:54:53 PM

Quote from: firstgenaddict on November 08, 2011, 02:58:39 PM

Lock washers will not retain their "lock" with the heat cycling on exhaust manifolds.

So they are not used on exhaust manifolds?

Title: Re: Exhasut Manifold bolt washers
Post by: Petes L48 on November 09, 2011, 12:29:49 AM

The middle ports did not have washers under the bolts.  The outer/end ports of the manifolds got the thick spacer washer, then a french lock, then the bolt.  The tabs on the french lock were bent over the bolt hex head to prevent loosening.  The order is important because you cannot properly bend the locks if the washer is in between it and the hex bolt head.

Here's pics of both the thick washers and french locks for SBC and BBs.  Factory locks were steel, most repops are stainless.
http://www.licorvette.com/french_locks_Corvette.htm

I can't recall exactly, but if you start adding a/c brackets etc to the manifolds you need to check your AIM to see if the french lock was still used or left off.

Title: Re: Exhasut Manifold bolt washers
Post by: sixt9x33rs on November 09, 2011, 02:07:53 AM

Thanks for the info Pete.