LarryD

I need to sandblast and repaint front and rear crush bumper shock absorbers. From the factory they are riveted on so I was thinking I would just drill them out and get new rivets. Even though I have a heavy duty pneumatic rivet gun, some of them don't look like I have enough room to get a gun into the hole area. Anybody see a problem with just replacing the rivets with bolts instead of new rivets??? Probably a lot cheaper to use bolts since I don't even know if replacement rivets are available anyway.

LarryD

Update and Follow Up on What I Did: I had the rear impact bumper blasted and powdercoated so just got it back today. For the blasting and powdercoat, I used a drill extension with a drill bit the same size as the center of the rivets to drill them out. You want to use a bit only as large as the center of the rivet. The idea is to cut just the top of the rivet head (inside the bumper cushion) and not drill into the cushion. You will be able to see the head spin once it comes loose. You might have to put locking pliers on the backside of the impact bumper to keep the whole thing from spinning (I had to do that on two rivets). Once the heads are off you can lift the cushion off the impact bumper. I used a punch to then drive out the rivet body stuck in the impact bumper (minus the head of the rivet). Once blasted and powdercoated, measured the hole size by using a couple of small bolts laying around the shop. I found the the coated hole size worked fine with a #10 maching screw, tight enough fit to work without having to remove powdercoat from the inside of the hole. So, I went to HD and picked up stainless steel hardware. I got #10-32x3/4 machine screws, 3/16 inch (id) by 1 inch (od) fender washers, and #10-32 nylon locking nuts. These fit really well on my bumper. With the impact bumper on a table with the cushion facing up, I dropped in the fender washers. They fit right in with a little bit of lateral play to make it easier to line up with the hole. Positioning the machine screw is more challenging. Although stainless steel shouldn't be magnetic, the ones from HD had a slight magnetism to I dangled them from a magnetic pick up tool and gently lowered them into position. Once started into the hole a little down force and wiggling the cushion gets the screws to drop through. I then put the nylon locking nuts on the back side. I didn't use any washers under the nylock nuts since they are self locking and the #10 fits the hole that a washer isn't needed. I left them loose until I got all of them in and then went through and tightened them all. My front impact bumper is out at powdercoat but the process should be the same when I get it back. Make sure you pay attention to how the old one comes off, that is, top of the impact bumper and top of the impact cushion. Before pictures will help you to reinstall.

Next up will be getting some internal push-on star washers to hold the impact bumper bolts in place while installing them on the frame rails. I took them all out to have the powdercoating done so that destroyed the factory internal star bolt retaining star washers. The fun will come in setting the shims correctly for the mounting bolts. I have the complete GM 92 Camaro service manual and it shows the measurement dimensions and how many shims are required. The rear impact measurements are taken from the back edge of the rear quarter panel so I can do that in the next week. However, the front dimensions are done from the front edge of the front fenders which I won't have back on the car for several weeks. I will start another thread on shimming the impact bumpers once I get that moving along.