How to repair rust under Battery tray?

Under my battery tray is all rusted through and I need to replace the area under the battery.

Do I have to cut out that area of the fender apron? or does the outer fender section just unbolt?

Does the replacement fender apron just bolt on or does it need to be welded?

Thanks

I have the same issue. I suppose its pretty common fo rour cars. I don't know the answer but hopefully someone here does. They look like they overlap and are likely welded, but I just don't know.

First of all, I really admire you folks who have welding experience and/or expertise. I have not had the courage to try it (something about my issues with fire.

As it relates to the battery tray apron, you will either have to replace the inner fender which entails drilling out a bunch of sport welds or you will have to cut out (it is not bolted in place) the offending piece and weld the replacement piece into the inner fender. I had the same issue on my '73 Grande and ended up ordering the battery tray apron from NPD (our sponsor {OMS} may also carry it). I had a local body shop do the work.

An article in the April 2004 issue of "Mustang Monthly" covered the procedure pretty well. Attached is a link to that article.

http://www.mustangmonthly.com/howto/173_0404_ford_battery_apron/index.html

Hope this helps.

BT

Yep, I had to cut the tray and apron out on the 72...it was RBR (rusted beyond recognition)! I got a replacement apron and battery tray kit from OMS. My situation makes it easier to install though because I already have the entire front off the car including the core support and headlight panels clear back to the shock towers. After the engine comes out, the rear aprons will be next to come out!

First of all, I really admire you folks who have welding experience and/or expertise. I have not had the courage to try it (something about my issues with fire.

As it relates to the battery tray apron, you will either have to replace the inner fender which entails drilling out a bunch of sport welds or you will have to cut out (it is not bolted in place) the offending piece and weld the replacement piece into the inner fender. I had the same issue on my '73 Grande and ended up ordering the battery tray apron from NPD (our sponsor {OMS} may also carry it). I had a local body shop do the work.

An article in the April 2004 issue of "Mustang Monthly" covered the procedure pretty well. Attached is a link to that article.

http://www.mustangmonthly.com/howto/173_0404_ford_battery_apron/index.html

Hope this helps.

BT

Click to expand...

If you don't mind me asking... what did the body shop charge you for the repair?

It was less than $200.00, BUT the owner is a very close family friend - - he actually grew up with one of my younger brothers.

BT

ah battery trays.

you basically cut out the area and either patch it or drill out the entire apron and replace the entire battery apron with a new one.

However the reproduction will be missing the reinforcement triangle/ 'L' bracket.

in the first picture you can just make out what is left of the original re-enforcement piece which is welded underneath the battery tray apron, it acts as extra support since the battery is very heavy and supports the tray under the battery better.

its often overlooked like the fuel Charcoal canister re-inforcement plate and the horns re-enforcement plate on the other aprons.

so you would either get one of those off a junk car in better shape or you can fabricate it or just ignore it.

put the process is the same, either your plug welding in a new apron or butt welding in a patch to the original panel.

its possible to braze in a new patch or even braze plug welds but it takes a lot longer then using a MIG or Tig welder.

actually starting to learn to weld on a apron is the best since that area will be covered up and you won't see it really.

I'd encourage you to get a small home mig welder (with gas) practice and tackle this repair yourself. This are will only require rosette welds so its a good first project. Given that I can see some rust higher up the tray I'd replace the whole apron section. Get the welder--get some scrap body parts from a junkyard and practice practice practice. Take a class at a community college whatever it takes.

Body work is expensive unless you know someone who is a good friend. And despite what you would hope and pay for--most places dont do restoration work--they do "fix it" work.

And Mustangs have one thing in common with Jeeps--they all have rust--and its hiding all over the thing lol

started by sanding then spraying a rust inhibitor and filled in the holes with epoxy then coated the whole tray with truck bed liner. If my welding skills were better I would have gone this route.

just remember you don't have to go crazy and feel like you need a mig welder, before MIG welding everyone brazed, all you need is a Oxy-acetylene rig from homedepot and some brazing rods for steel. i think the entire rig cost me 50$ Home depot sells the canisters also. red and yellow bottles. look for it in the tools section.

before i bought a mig welder i would braze weld everything. now for body work this isn't so good because the heat will warp a panel, but for the engine bay it can be a good start.

just cut out the area then fit the patch in, get some strong magnets to hold the panel at the cut line to make sure its all lined up. fire up the Oxy-acetylene , then tack weld the panel in.

then go back and fill in the cut lines, finish up with a sander or file, then you can either throw some seam sealer on it or just epoxy paint and top coat.

the rust shown above would be a major thing to just cover up because it would barely support the battery weight. you don't want 30-50 pounds of battery breaking free on a pothole or sudden stop.

you can also replace entire sections in the engine bay with brazing, you drill out the spot welds with a spot weld drill, pop the old panel out then drill holes in the new panel where the spot welds were on the old panel, Line it up sand off the primer on the new panel and clean up the old one. then you plug weld, you braze on the areas that the spot weld was in.

you don't weld the entire panel all around just where the original spot welds were, then clean up with a sander and prime and paint. that would be more involved since you would have to remove more parts from the engine bay, like the rad. just patching the bottom of the battery tray could be done from wheel well just pulling the plastic fender debris shield out, and you should have the room you need to work from underneath.

just a thought for the future.

I had this same issue and went ahead and replaced the fender apron. If you get your self a spot welder cutter it is easy to replace and the just make some new holes in the new piece and spot weld back in place. Now if this corrosion has moved to the front frame extension you might run into other issues. This is what happened to me and i needed to replace the front frame extension and weld in another that I managed to pick up at a salvage yard.

If I replace the Front apron, is the front fender easy to reove and put back? Any special allignment considerations before removal?

What elso do I need to remove inorder to replace the apron?

Radiator? Preferibly the least possible.

This is a timely topic for me, as I'll be replacing my battery apron this week. I've already drilled out the spot welds and removed the old panel, and I am fortunate to have a mig welder, so we'll be welding the new apron in place. However, before we started work on our 72, I had a good friend give me some advice about these kinds of projects. He said, just because you CAN repair something, doesn't mean you SHOULD. He wasn't talking about original, difficult-to-find parts, but his logic was this. With the time it would take to remove, fabricate, fit and install a small repair to a panel like a fender apron, in some cases, it may be better and cheaper to simply buy the replacement part and install it. My apron cost $39. And as much as I enjoy working on my Mustang, my project list is pages and pages long. For me - it's a better approach to buy the entire battery apron, install it and move on to the next project.

As 72HCODE mentioned, this is one of a few perfect places on the car to jump into welding, if you're inclined to do so.

Whichever route you go, would love to see some pics of the completed repair!

Mark

started by spraying sand and a corrosion inhibitor and fill the holes with epoxy, then covered the entire plate lined truck bed. If my welding skills were better, I have followed this path.

I recommend you to buy the Paintucation series from Eastwood. He will show you everything you need to know to tackle this yourself.

You will learn a new skill and save yourself ALOT of money in the future.

I am going to repair a badly rusted inner fender well on my 1973 Grande. can anyone tell me a) if the fender needs to come off, and b) how many spot welds I will encounter and where?

Thanks guys and gals!

I got a reproduction apron and I just cut out the area I needed for my repair. Also I purchased the reinforcement bracket underneath off of epay, seller's name Dan. This guy makes the aprons one piece at a time, he's ingenious! And it looks just like the original! After everything was cleaned up and "rust free" the pieces got welded in and you couldn't even tell the repaired area. I do not remember Dan's full username but perhaps if you look up battery apron he might pop up.

For comparison, my original piece cleaned up and Dan's reproduction battery reinforcement bracket!

Made my own pieces. Advantage of working in sheetmetal for a living.