66 rear bumper bolt /washer question

[Robert P.]

putting rear bumpers back on my 66 and wasn't sure if there are flat washers under the bolts going thru the the bumpers , the AIM shows none , picture in the 66 judging guide shows none page 88 but the description on page 88 says all with flat and lock washers per side . i am planning on none as the AIM and guide shows
Bob

[Alan D.]

Re: 66 rear bumper bolt /washer question

Re check AIM UPC 14 sheet B1, flat & lock

[Gary B.]

Re: 66 rear bumper bolt /washer question

Bob,

When I looked into the bumper fastener question fifteen or so years ago, this is what I came up with. There are 22 bolts at the rear that are associated with the bumper attachments, either directly with no bracket, or via brackets and braces. I came up with a total of 30 flat washers at the rear, meaning some bolts take two fiat washers, one under the head and one at the nut end, between the lock washer and the frame or where bracket attaches to the bumper.

Just this last week I re-examined my baggies of original, unrestorable, rear bumper fasteners for my ‘66 and I found 29 fiat washers for the rear. Because of left-right symmetry, there should be an even number of flat washers. So, either I lost one flat washer when I bagged them up 25 years ago, or one bolt didn’t get a flat washer that its twin brother bolt on the other side did get. Or a third possibility is that one bolt got two flat washers that were stuck together. I have a photo of an unrestored ‘66 or ‘67 with such a double flat washer mistake.

There is an amazing number of bolts, nuts, flat washers and lock washers associated with the bumper attachments and I can imagine that every so often one fiat washer was missed by the worker on the production line.

I don’t know if this helps to answer your specific question.

Gary

[Joseph S.]

Re: 66 rear bumper bolt /washer question

Bob, There should be no flat washers between the head of the bolt and the bumper bracket. The locks and flats are on the nut side.

Once you get inside of the body, all the brackets attached to the frame get 2 washers per hardware set. One flat washer at the bolt head and another flat washer at the nut side. This is necessary since the brackets and frame are slotted for adjustment.

The one area on the quarter panel where there is no bracket also gets a lock washer and flat washer against the head of the bolt that threads into the bumper. be very careful tightening this bolt since you can crack or damage the fiberglass. I always do this bolt first.

I hope this helps.

Joe

[Gary B.]

Re: 66 rear bumper bolt /washer question

Bob, There should be no flat washers between the head of the bolt and the bumper bracket. The locks and flats are on the nut side…

Joe,

To be clear about what you’re referring to when you say “bumper bracket” in your first sentence, I assume you’re talking, for one example, about the one at the lower right in this sketch from the ‘66 AIM, where there is no fiat washer adjacent to the bolt head.

IMG_5689.jpg

Maybe another way to describe is that flat washers are not used adjacent to bolt heads where they would directly contact the (chromed) surface of brackets welded to the bumper itself.

Gary

[Joseph S.]

Re: 66 rear bumper bolt /washer question

Gary, There are bumpers and there are brackets. If the bolt is against the bumper there are no washers. If they are against brackets then there are washers.

[Gary B.]

Re: 66 rear bumper bolt /washer question

Joe,

I agree in general. It’s just that the bumpers also have what I would call brackets welded to them. Hence a possible confusion when using the word “bracket”. Are we talking about a separate bracket, or an integral bracket welded to the bumper.

Gary