BOOT77

Just drilled a hole in the wrong spot on my firewall and I want to seal it back up. It's in a spot where I need it to be flush again so a grommet won't work. I'm unfamiliar with any body repair let alone fiberglass repair.

The hole is about 5/16 diameter, from my researching it looks like I can use bondo? Specifically bondo fiberglass resin jelly came up in my search as something I can run out and buy at any 24hr wal-mart. It'll be mostly covered up so I am not worried about looks and I won't be drilling any of that spot again.


Still searching some to see what other options are and was considering epoxy but idk what kind would be best. I'm not looking to use the fiber sheets and sand it all down. Still figured I'd post and ask while looking. I'd just rather not have it fall out and have to redo it later if I use the wrong stuff.

Thx for any advice

Rotonda

For only a 5/16 hole, I would; 1) enlarge/taper the surface of the hole on both sides, 2) place a tape backer over one side (I cut a small circle of wax paper and past it on the sticky side of the tape to help release it later), 3) mix and apply JB Weld to the hole, pressing it into the hole so that the tape/wax paper will bulge slightly. It may require more than one application. The goal is to have a small mound protruding from both sides. 4) block sand the protrusions smooth and flush with the surface. 5) paint.

BOOT77

Don't really wanna make a mess by sanding or painting since the hole is right next to the engine. Too close too taper the hole with a power tool so I'll just have to try an trim it some with a razor maybe.

Glad you brought up wax paper, forgot I saw some1 use it to mold a piece the other day. It's the heater core hole and I am installing a cover over it. The hole I drilled is right on the edge of the cover(2/3 under). I should be able to just clamp two wax paper covered pieces of metal over both sides of the hole.

I could use some of that fiberglass cloth on the back side I suppose.

I wanted to finishing sealing up the new AC/heater delete cover and cruise it tonight, but I suppose I could just put the dash back together and take it apart again later.

AkrHack

JB Weld also makes an epoxy putty that you can use to fill the hole. It works great for small repairs like this.

Sayfoo

Black rtv silicone?

redvetracr

a hole that small that will be covered up thats what I would do

7T1vette

Go with the 'stick' epoxy made by JBWeld. It will fill the hole, then you can use a putty knife to scrape it smooth with the surface. Five minutes later it will be hard and you can put a little primer on it, then spray some John Deere 'Blitz' black to make it look like original blackout on the surface.

BOOT77

RTV would be easy and I guess it is covered up not like it'd come out. IDK I got a week to figure it out now and I'd like to maybe try some fiberglass or epoxy I think. Thanks for the ideas & info.

Bikersully

I would go the black RTV route.