65 rear bumpers stressing fiberglass??

[fredd65]

i'm putting my 65 back together and doing the rear bumpers....i'm wondering how much stress the fiberglass can take in the back...when i put the bolts in at the rear of the car and snug them the bumper angles down, so then to put the bolt in around the corner on the fender i have to pry the bumper up so the hole lines up...i can pry it up with one hand so it's not that bad....i have it all in and tightened and no cracks now, but should i worry about a stress crack later when i drive it?....i bought the car in the middle of a half assed restoration project with the bumpers off and started over, so i don't know how it was taking them off...thanks for any help

 

[JohnZ]

I wouldn't worry about it - those things weren't "precision-fitted" to begin with; if all it needed was hand pressure, it's not a problem.

 

[WayneC]

I don't think it's uncommon for the bumper to be a little warped, especially if it's ever been hit. So it might be good to secure the rear bolts to something solid and over-bend the bumper end upward to regain the proper shape.

If (while tightening bracket to frame bolts) the side bumper bracket was lined up with the hole in the fiberglass, and the rear corner bracket lined up with it's holes in the fiberglass, then there shouldn't be much stress on the fiberglass. If the side hole doesn't line up, then either the brackets need a little "tweaking", or the side fender bumper hole is not in it's proper position. The deciding factor is probably whether you end up with a "smile"... ie, the bumper end is pointing uphill when the bumper is secured in place, which might indicate the side fender hole is not in it's proper position.

 

[paintdaddy]

I understand what your talking about.I have ran in to the same problem with early c3s.Ive seen a few guys put soft rubber pads on both sides of the fiberglass to help ,its not full proof but it helps.
Ive even had problems after putting the bumpers on while on a lift then when letting the car down it will crack the glass sometimes.Hard to believe but the frame flexes more than the glass .

 

[IH2LOSE]

fred65

How do you know you have all of the brackets correct do you have a manual or onther car to compare it to.I know on the front its easey to mix them up thats a problem I had and could never aline them correct in the front .

Also do you have any shims? This winter I am redoing the rear bumper brakets and bolts on my car and the little I played with them them Installing the shim in one place or another really changes the angel/attitudeof how the bumbers fit.

Good luck.

 

[fredd65]

65 rear bumper positioning

to get the one side hole to line up right i had lift fairly hard on the bumper...i wonder if i should i redo the shims to take that stress off...the idea of a lift scares me...that frame really does flex!...any thoughts?..thanks

 

[paintdaddy]

With out looking at what your working with exactly ,I would say redo the shims and if your not real concerned with originality ,put some kind of soft foam rubber on both sides or at very least just the inside.When you tighten the bolts dont crank downhard just get them snug.Maybe after the car has been driven a little then tighten them a little more but ,again,dont crank down on them.That would be my suggestion.

 

[JohnZ]

The shims will just move it fore-aft; won't affect its angularity from horizontal in the side view. Make sure you have all the brackets and braces oriented correctly per the A.I.M., and tighten the bracket-to-frame bolts last.