W123 - Advice needed on jack point rust
 

bodywork experts,

I just got winter beater 85 300D, and I am getting it ready to go. I poked around at the one major rust area, the front jack point / rocker panel.

I discovered quite a bit of rust after stripping the chunks away.

Outside front driver's jack point area:
http://i414.photobucket.com/albums/p...08/mike012.jpg

Inside the driver's footwell:
http://i414.photobucket.com/albums/p...08/mike015.jpg

This car is not going to be a show car. I just want to make it last a while (5 years?) as a winter car. what's the best way to practically repair it? looks dont matter.

I have plenty of POR-15 and fiberglass cloth and bondo waiting. I don't have a welder, although I could access one. I am leaning towards coating in POR-15 and then using fiberglass cloth + bondo to fill the gaps since the area is not structural and full of complex curves that would be hard to fabricate.

Thanks,
dd

diesel,

i've done exactly this type of repair. the jack hole is part of the inner rocker panel support. if its rusted through, there's no way it can be reused. take a look at my blog in my sig, and read my Feb 14th, 18th and March 16th entries. if you want detailed advice, please email or PM me.

you sir, are a rust warrior...my goodness thats a lot of work and a labor of love. I hope the engine runs well :-)

The jack point itself is not ruster through, just the rocker panel around it.

I guess the main difference between us is that I need to get this car on the road in the next couple of weeks before they lay salt down on the roads ( so I can get my rust free car away from all salt :-) ).

Would you attempt this fix with fiberglass? I cant access the area as easily as your 124, there is a sheet metal flange in the way. All my welding (if I somehow acquired a MIG and learned to use it) would be inside the cabin, around the flammable foam. I can take some better pictures.

dd

Update - help....
 

Removed lots of the rust today. Its bad.

http://i414.photobucket.com/albums/p...8/lance001.jpg


http://i414.photobucket.com/albums/p...8/lance002.jpg


As I removed more, I found it had rusted a lot of the floor:

http://i414.photobucket.com/albums/p...8/lance007.jpg

http://i414.photobucket.com/albums/p...8/lance008.jpg

http://i414.photobucket.com/albums/p...8/lance009.jpg


I have driven this car less than 2 miles since I bought it. I was not expecting this at all. If I had known I wouldnt have gone poking.

What would you do? I need help...

If this is just a winter beater, I would treat the rust with POR-15 and then glue in sheet metal using pop rivets and JB Weld. Then coat that with POR-15 and top coat, then use rubberized undercoat under the car.

You could try welding in as much as possible and then finish it with the JB-Weld and pop rivets.

Chad, do you own stock in the JB Weld company?

You definitely need to weld in metal. This is a "unibody" car and the floor panels are the main lateral support.

No, but I probably should.:D

Thanks for the advice guys.

I have never welded before, so this may be the time to learn. I can't see completing everything by welding, I will probably need an eclectic mix of techniques for this.

How do I weld inside a car without it catching on fire?

and...

Anyone every use the POR-15 epoxy putty for this sort of thing?

dd

I used the putty in addition to the fiber sheets from the floorpan kit sold by POR-15. I repaired my rear floor and it is holding up very well.

The only way to keep the car from catching fire while welding is to remove the undercoating far enough from your welds and use a welding blanket to cover everything else. That's why I recommend using a combo of welds and JB-Weld or some other epoxy to glue some sheet metal in place with pop rivets.

I would go through the effort of stripping the car for full welding if you were expecting more from this car than being a winter beater.

Thanks Chas.

The cars purpose is as a winter beater and summer backup car for hopefully several winters. Ironically, there are no other major rust spots like this one. The undercarriage is fine.

Im happy to hear the POR-15 kit is working well for you. I have their fiberglass and epoxy putty waiting. I thought that would be all I would require.

Im really at a crossroads as to what to do.

Slap POR-15 everywhere, fix it with fiberglass cloth and epoxy putty and go. See how the car acts (i have only driven it 2 miles since buying it) for a year and re-assess.

OR

Buy a MIG welder and fashion in as many new pieces as I can using 16 gauge steel, filling gaps with cloth and epoxy putty.

Either way I wasn't expecting to put in this much effort before winter, so Im bummed.

Whats a good stripper for the undercoat?

dd

I can cut you a panel from a rust free car, that you could just weld in for $50 plus shipping

A heat gun and a chisel/scraper.

Quite a few new cars a being assembled with epoxies. I think you might get away with glueing in sheetmetal with Pop rivets for extra strength. I couldn't guarantee how it would hold up in an accident, but it would drive around fine. The repair I did on my floor board took a good whack with a 3 lb hammer and didn't crack or budge.

I wouldn't rely on the fiber sheets alone, but sheetmetal glued in and pop riveted and then coated with the fiber sheets will be VERY strong. I also use POR-15 paint with the fiber sheets, not resin.

Update
 

Well I took the plunge and got a MIG setup (Lincoln Electric Pro 140) to fix it right. I have some 16 and 22 gauge to weld in there.

(thanks for the offer to get a whole piece to weld in there, but I think it would not be easy to put in several surfaces like that.)

My questions -

1) should I work outside in, or inside out?

2.) for welding on the inside, as long as I back the insulation far away enough, do I need to take the dash out? or can i carefully cover the dash with welding blankets?

dd

dd,

btw, where are you in boston? spent 2 years at babson for grad school. somethings i miss about beantown, but not much ;)

have you gone through my blog? alot of the questions you asked are pretty well covered in there. I would reall take that person's offer for the rocker part for $50. you are getting a steal. not to mention, you will save yourself a TON OF HEADACHE.

as for catching things on fire, the most flammable stuff I found was this foamy black brittle material located at the front driver's side. i didnt find anything like that anywhere else. there's interior mastic which I took off by heating it w/ a mapp torch and a scraper. just wave it over a small 8 inch section at a time.

i know what youre worried about re catching things on fire. just make sure to spot weld from one end to the other with each spot weld being about 1" from each other. for example:

section youre going to weld:
-------------------------------------------

start a spot weld at each end:
X-----------------------------------------X

maybe put 2 to 3 in the middle:

X-------X-------X---------X--------------X

then work from one end to the other:

X----X-----X----X------X------X----X----X

the key is to allow the metal to cool.

also, be aware that galvanized steel is not good for you. i always powered a fan at speed setting 1 and held my breath when welding. and make 110% sure that you're welding bare metal. youll quickly realize that the ugly welds are usually caused by unclean metal.

email me for more tips and/or clarification re my blog entries. trust me after you read it, you'll have acquired a year's worth of hard earned knowledge!

bob