RC COLA

Hello,
My Cherokee is in the shop for rust repair. The leak was traveling from the cowl into the fresh air intake. I pulled the carpet and found significant rust on the floor pan.

I took the Jeep to my mechanic (not a body shop) to fix the leak. He fixed it and I asked if he could refer a body shop. He said he could do the work and I said great since he's a friend and I get the buddy discount.

At first he recommended a fiberglass patch but I told him I wanted new metal welded in for durability. I'm worried he's going to cut too much of the floor? (see pic) The rust is only on the left corners of the floor pan near the transmission tunnel. The rust is limited to two small areas, a few square inches each. He has a relatively thick piece of steel he's going to try to shape to match the floor. I thought purchasing a new floor pan and using part of it was a better option.

I'm also considering having the floor bed-lined for added rust protection but I'm second guessing if this will do any good? Thanks for any help you can provide.

Pass floor pan. Rust is on left corners of the pan.



rovide.

PatHenry

Hahahaha... "significant rust" --- Come up north if you want to see what significant rust really looks like!!

All fun aside - you can certainly get a pre-fitted floorpan and use that to weld in. A bit of shaped steel will work just as well. Where you're at you can probably just hit the junkyard and cut out a good piece of metal (get several inches overlap just to be safe) and save yourself a hundred bucks.

You can line the floor if you want - I'd do something since you don't want the new metal bare.

RC COLA

Thanks PatHenry, we're a little spoiled with rust free cars in California so this seemed significant to me. I was expecting just surface rust when I pulled the carpet.

I just spoke to my mechanic and they fiber-glassed the holes and they are going to leave the stock floor pan in place and weld the new steel on top of the old floor pan. He said it will weaken the unitbody if he cuts out the floor pan. He said if it was his car this is what he what he would do. I'm worried that the space between the floor pan and the new steel could rust. I'm just praying he knows what he is doing.

boxburn

Personally I'd just cut out the rot and weld a new bit of sheet on top. My floors were a hell of a lot worse than that but being able to do the work myself, I just patched/replaced. A new floor pan would have been a better option but they're not so easy to source for me and my own time costs me nothing.

If it's within your price range to bed-line it and you plan on keeping it for a while, I don't see a reason not to do it. If it were bed-lined before your water leak, you could find that it wouldn't have started to rot depending on how long it was left.

Just make sure that the new metal is properly sealed inside and out before any moisture can get in at the overlap of the existing and new metal, that's one of the biggest killers of patches I find.

boxburn

To add on to your reply to Pat, we use a spray called Weld-Thru Primer or Zinc/Alu spray. It is a weldable paint that helps protect the bare metal in the overlap areas. I cut all of my rot out as you can see in the pics as I don't like leaving bad metal under a repair. I wouldn't say I've lost any structural integrity by doing so.

PatHenry

If you cut the floorpan and weld in metal of the original thickness or greater in it's place it will maintain the strength of the unibody. Really, if he welds a piece of metal of the original thickness or greater over the spot, it will be fine.

If moisture can't reach the metal, you won't get rust. You could take a can of flex seal, rubberized undercoating, bed liner, etc and so long as it covers and sticks to the metal and doesn't let moisture in, you won't have to worry about it. If there is a gap, you can put some seam sealer on it or use any durable automotive caulking/sealant to fill the space and then coat over it.

Make sure to use protection on both sides of the floor.

boxburn

This.

PatHenry

Hahahaha I didn't see your posts until after I posted that - I thought you said it better!

Anyway - O.P., obviously the point is "keep the moisture out and it shouldn't rust"

For the record, my rot was even worse than that (staring at bare frame rails the length of the cargo area on the passenger side). And my repair was not nearly as well done as boxburn's - but it's sealed up and hopefully will last the rest of the vehicles life.

RC COLA

Thanks boxburn, I'm going to bedline the floor and I'll make sure that the new metal is sealed and he uses a weld-thru primer.

Thank you, I feel much better about his approach to the fix. I'll make sure both sides of the floor are sealed. I just realized that I likely won't be able to keep the stock drain plug hole because he's going to weld metal over it. If he cut a hole in the new metal for the drain plug moisture could get in between the two layers if there's a gap.

PatHenry

It should be simple enough to relocate the drain plug by cutting a hole of the same size in an appropriate location nearby. At worst he may have to reshape the pan a bit to make sure water flows to the new plug, but that should be easy enough to do.

RC COLA

I just spoke to him and he's going to leave the drain plug in the stock location by cutting a hole in the new metal above the stock location and seal around the hole. Can't wait to get the Jeep back, been in the shop three weeks!!

PatHenry

On a side note - have you named your Jeep "Elizabeth Warren"??

I mean, it's white, it's well outside of the mainstream in 2019 and it claims to be a Cherokee but less than 1% of the people involved in making it were full blooded Native Americans.

All joking aside, interestingly enough, Chrysler was actually recognized for being a top employer of Native Americans - which is great, but it does take away a bit from my being able to mock my state's delusional Senator "Chief Spreading Bull" aka "Fauxcahontas", aka "Granny" Warren.

RC COLA

Wow that is hilarious! I've always known my Jeep was a girl but I've never named her. I just had someone ask if I had a name for her... now I do! LOL

PatHenry

Hahahaha!! When I was a kid my first car was an 86 Firebird - a buddy named it "Queasy".

99CherokeeClassic

Does anyone know where to find a door to door floor panel/pan?. I have extensive floor rot and only find driver's side and separate passenger side floor pants which are not big enough to cover the rust hole on my '93.