Filling in large holes

[KLF]

Prepping to paint the engine compartment on my '87 mini. Cab is stripped to sheetmetal, nothing in the way. I am not going to re-install the factory AC, so I want to fill in the holes in the firewall from the freon lines and the condensate drain, the biggest hole is about 1-1/4", perfectly round, no rust (see circled holes). Looking for the best way to do this, mostly I want to make sure it's water tight. I have a welder and some 16ga steel, but not sure I wanna attempt this. What about some sort of 3M body sealant and pop rivets? Epoxy a patch from the inside?

Thanks.

 

[Jetboy]

Do you care what it looks like?

 

[KLF]

This is not a museum piece, so not really. I don't think I can weld a piece in that will make the hole disappear, I'm not that confident and I don't want to spend a lot of time on it either. So a patch glued in from the inside with some paintable sealant would be fine with me.

 

[TRAIL TAILOR]

This is not a museum piece, so not really. I don't think I can weld a piece in that will make the hole disappear, I'm not that confident and I don't want to spend a lot of time on it either. So a patch glued in from the inside with some paintable sealant would be fine with me.

Patch and paint is a quick idea.. I've welded washers in and then either "rosette" welded the smaller hole or slug welded it by some people's term.

Either will work but, patch might come loose after time.

J

 

[fieldsken1]

leave it and put in a rubber plug in case you change your mind later

 

[Jetboy]

I would cut a metal patch larger than the hole. Put it on the inside, then weld around the ring. Then you can bondo the hole from the engine side. It would be easy to weld. You can grind it smooth quickly because it's recessed so only the top of the bead will need to be knocked down. And the inside will probably be covered by carpet so you won't see it. On the engine side, bondo can fill the hole and it will look nice and clean.

This would be a good long term fix and probably take only an hour or two to be ready to paint.

 

[toydude13]

Why make a large project out of it?

Use rubber plugs and give yourself future options.

 

[Splangy]

I would cut a metal patch larger than the hole. Put it on the inside, then weld around the ring. Then you can bondo the hole from the engine side. It would be easy to weld. You can grind it smooth quickly because it's recessed so only the top of the bead will need to be knocked down. And the inside will probably be covered by carpet so you won't see it. On the engine side, bondo can fill the hole and it will look nice and clean.

This would be a good long term fix and probably take only an hour or two to be ready to paint.

Why not just weld it in flush and grind it smooth? Same amount of work and a much better result.

 

[79fj40moneypit]

go get a cap plug from your local auto pats store, push it in. done

 

[KLF]

I'll check my parts stash, I may have something like that. I'd prefer it to be more permanent, but I suppose a rubber plug would be OK. Certainly a lot easier!

 

[tag3]

Use the rubber plug, you can feed wires through it later if needed.

 

[Jetboy]

Why not just weld it in flush and grind it smooth? Same amount of work and a much better result.

He said that he didn't feel like he could do a good job welding in a round blank. That's an easier way to do it that's really hard to screw up.

I'd probably buy a couple $4 firewall plugs myself.

 

[KLF]

You guys talk about these rubber plugs like they sell them on every street corner. I've been to 4 auto parts stores and 3 hardware stores, I can't find them. Not AutoZone/HomeyDepot stores either, I'm talking good stores with people behind the counter that can find stuff without a VIN. Nothin.

I did find an OEM floor plug in my parts stash for the largest 1-1/2" hole. Now I just need a plug for the other two 1" holes.

 

[Jetboy]

Here's a couple options:

SoffSeal 0185 SoffSeal Rubber Stoppers/Bumpers/Plugs

1-1/8" Sheet Metal Plug - Round - 4 pcs/box at Menards

Locally I'd look at a place like maybe a large ace hardware or similar that has a big selection of assorted hardware.

 

[tag3]

Check out Fastenal.

 

[Splangy]

He said that he didn't feel like he could do a good job welding in a round blank. That's an easier way to do it that's really hard to screw up.

I'd probably buy a couple $4 firewall plugs myself.

I agree, I would just plug them with grommets, too.

But, he did seem like he was looking for a more permanent solution. Plugging a firewall hole would make excellent welding practice. I would practive on some scrap, first. Welding in a few small patches like that with 16ga would be pretty easy, even for a beginner.

 

[KLF]

Jegs charges too much for shipping, then they tag on an extra delivery fee for me, probably because I live kinda out in the boonies. One stupid rubber plug would end up costing $25 I bet.

No Menards in NH.

I went to one ACE and 2 Aubuchons. They all have a huge hardware sections, the kind with all the trays of stuff. Nothin.

My experience with Fastenal is they will want me to buy a box of 50. But I will be driving right past one tomorrow, it's worth a shot.

I did get a lead from one parts store today, they told me of a place not far away that specializes in body shop stuff.

Thanks for the suggestions! Greatly appreciated.

 

[WarDamnEagle]

Did you look at McMaster Carr? Their shipping is usually pretty reasonable and they have just about everything you can dream of. I source stuff from them all the time.

 

[Icantdive55]

Did you look at McMaster Carr? Their shipping is usually pretty reasonable and they have just about everything you can dream of. I source stuff from them all the time.

X2 on Mcmaster Carr i use them a lot. Then there is MSC and kimball midwest. They have huge selections as well.

 

[Splangy]

Jegs charges too much for shipping, then they tag on an extra delivery fee for me, probably because I live kinda out in the boonies. One stupid rubber plug would end up costing $25 I bet.

No Menards in NH.

I went to one ACE and 2 Aubuchons. They all have a huge hardware sections, the kind with all the trays of stuff. Nothin.

My experience with Fastenal is they will want me to buy a box of 50. But I will be driving right past one tomorrow, it's worth a shot.

I did get a lead from one parts store today, they told me of a place not far away that specializes in body shop stuff.

Thanks for the suggestions! Greatly appreciated.

Dude, I didn't even realize you were a fellow southern NH mudder! I have a bunch of body plugs. I'm pretty sure some 1" and maybe 1.25" and 1.5". If not, I'm going to the Amherst car show/flea market (never any Land Cruiser parts there) tomorrow AM. There's a guy there every month that sells body plugs in various sizes. I'll probably drive the 40 there. PM me for details. Where are you located? I could probably just weld them up for you if you're close enough to me.