1966/67 BB radiator support bracket question

[R N.]

Hi Everyone,

I'm sorting out what should be the correct configuration for the bolts, lock washer and large flat washer that attached the upper radiator brackets in place. These are the bolts you can see on the top forward side of the radiator support. My car is a March 1966 built L72.

On my car, the two outer pair of bolts have two larger washer (first photo), while the center pair of bolts (second photo) have one large washer. The judging manual makes no mention of two washers, plus the outer pair of bolts have two different washers - one is much thicker.

Would someone confirm what is the correct confirgration - THANKS in advance.
photo A.jpgphoto B.jpg

[Gene M.]

Re: 1966/67 BB radiator support bracket question

Kurt, they should all be the thicker washer.

[Ronald L.]

Re: 1966/67 BB radiator support bracket question

Gene, not clear what you mean and you know at NOVI 2011 we looked at a pair of bow tie cars that had thick washer and then the thin one, not double thick, and not just one thick washer.

[R N.]

Re: 1966/67 BB radiator support bracket question

Gene, not clear what you mean and you know at NOVI 2011 we looked at a pair of bow tie cars that had thick washer and then the thin one, not double thick, and not just one thick washer.

Hi Ronald,

By chance would you have any pictures to share? Thank you.

[Ray G.]

Re: 1966/67 BB radiator support bracket question

Kurt;
As recently as 2008 the concave, thick, large 427 radiator support bolt and washers shown in AIM page G363 were available from Chevrolet Parts.
As I remember there was a part number change, which I can't find right now.
Maybe Joe Lucia has the number. Will post number and picture when found in my storage.

[Gene M.]

Re: 1966/67 BB radiator support bracket question

Gene, not clear what you mean and you know at NOVI 2011 we looked at a pair of bow tie cars that had thick washer and then the thin one, not double thick, and not just one thick washer.

Ron,
I'm sure you will find original cars with all (one per bolt position) of the thick washer. I know of some cars/people that also in addition to the single thick washer to have another thinner one. Were cars built both ways? Anything is possible.
I would expect to see at least the thick washer, but the addition of the thinner one I would not preclude as wrong.

It is my opinion that two thin washers is an aftermarket parts supplier's wet dream. I don't have my AIM nor judging manual handy to see what they say.

[Matt L.]

Re: 1966/67 BB radiator support bracket question

hi Kurt,
i hope these pics help you. these are from my very original 66 L72 built in mid april. it is an AO smith body. i am not sure if that matters or not but i hope it helps. the outside mounts have 2 washers. one thicker than the other. the middle mount looks to have the thinner washer of the outer mounts plus a lock washer.
take care,
Matt66 corvette radiator bolts 003.jpg66 corvette radiator bolts 001.jpg66 corvette radiator bolts 002.jpg

[Ralph B.]

Re: 1966/67 BB radiator support bracket question

Who carries the thick washers ----------- they appear to be about 3/16 thick?

Ralph

[Ronald L.]

Re: 1966/67 BB radiator support bracket question

I my experience the repo's do not match originals.

Thanks for the picture help Matt!

Gene, what Matt has shown is how the 66 AIM has them, different at center.

Two thin - agree not. Two thick washers - not.

[R N.]

Re: 1966/67 BB radiator support bracket question

hi Kurt,
i hope these pics help you. these are from my very original 66 L72 built in mid april. it is an AO smith body. i am not sure if that matters or not but i hope it helps. the outside mounts have 2 washers. one thicker than the other. the middle mount looks to have the thinner washer of the outer mounts plus a lock washer.
take care,
Matt[ATTACH=CONFIG]45111[/ATTACH][ATTACH=CONFIG]45112[/ATTACH][ATTACH=CONFIG]45113[/ATTACH]

Hi Matt<

Thank you for taking the photos and for posting them. This really helps - my car is configured the same as yours. My car was built March 25th (VIN 17534) Also an AOS.

[Ronald L.]

Re: 1966/67 BB radiator support bracket question

These parts were St Louis assembled parts so for the application, the important point is what they look like, Matt's car is one of the best surviving examples of an un molested car.

[Ralph B.]

Re: 1966/67 BB radiator support bracket question

I my experience the repo's do not match originals.

Thanks for the picture help Matt!

Gene, what Matt has shown is how the 66 AIM has them, different at center.
Two thin - agree not. Two thick washers - not.

Ron,

Having trouble locating anything showing use of double washers in AIM?

I do find washer 3688003 with lock washer 103320 specified in AIM L72 B1.

From what I can determine washer 3688003 is 1.25 O.D. X 11/32 I.D. X 3/32 thick which I assume based on the pictures would be one of the "thin" washers? --------------- @ 3/32 (.093) thick it's still thicker than some of the repros that run as low 1/16 (.062).

As far as function goes, I can see why factory incorporated either double washers or very thick washers which was to spread the force further away from the hole to avoid localized crushing ------------ especially on early 66 cars that did not have the spacers (tubes) on the very outer holes to prevent this.

Thank you,
Ralph

[Ronald L.]

Re: 1966/67 BB radiator support bracket question

Ralph, not clear what your question is, the picture matches the aim and the picture shows how they were built. At least through the end of April the supports did not have tube reinforcements and yes they collapsed quite a but. Matt's car is un molested and shows little indentation in the outboard attachment.

[Ralph B.]

Re: 1966/67 BB radiator support bracket question

Ron,
The pictures that show the single large diameter "thinner" washer with lock washer matches the AIM and JM, it's the pictures of double washers (1 thick with 1 thin) with no lock washer that I can't find any reference to ?

[Ray G.]

Re: 1966/67 BB radiator support bracket question

Hello;
Agreement here that Matt Lewis images are a true depiction of '66 & '67 radiator support with the caveat his images are from early support without the interior reinforcement sleeves at the the end bolts.
Another crucial fact is these "thick washers" are actually SHIMS. Slightly concave to lock the shims against the core support.
I'm unable to find the part number at this point, but will look again when returning to the snowy north.
Richard Fortier has a reproduction of these shims (washers), in the Driveline.