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frame rust spots (2 small) on '99 Jaguar XJ8. Can it be SAFELY repaired?

I have a '99 Jag. Body like a new car. Purrs like a kitten. I let it set for 2 years because it needed coil packs replaced. Now it has a slightly surface rusted oil pan, tranny pan and brake line couplers. All the brake lines themselves are fine (they are coated). The under body is solid, not even surface rust. BUT there are 2 spots the size of 50 cent pieces of rust on the front frame. No holes but the rust extends through, one on each side front frame. Can this be SAFELY repaired? The rest of the frame is perfect and even around the 2 spots is solid without even any surface rust. I LOVE this car and HATE to part it out.

seandogue2 years ago
Yes, if you intend to do it yourself, make sure you use TIG. Neither gas nor MIG welding is suitable for frame repair.

As others have noted, it's probably best for a vehicle like this to have a pro do the work, since they'll be able to treat any hidden corrosion during the repair operation.
You say that, but I know an AMAZING shop here who ALWAYS gas welds frames, and his results are unbelievable.

He reckons TIG on rusty frames is very problematic.

YMMV

Steve
I've done the same, (67 Mercury cougar years ago) but I was soundly "reprimanded" in public by several people (actually four people, two of which knew each other at NASA, one a 20 year veteran welder who worked on civil projects, and the other a 10 year vet who worked in a machine shop) for doing so after mentioning it, apparently due to a tendency of gas welding to yield a less durable weld that rots from the inside out. I'm a pretty good gas welder, but not a professional who has been doing routinely for years in a mercantile environment. I'm sure that a well seasoned professional can do it quite successfully, just as a professional welder can weld incredibly thin materials.

As to welding a rusty frame, I would expect that one would remove the rust and treat surround materials prior to patching on such a critical component of a luxury sports car.

The advise is based on someone who asks a question like the one noted here in this query.
acidbass2 years ago
it should be able to be safely repaired......use a spackle spreader or a scraper and go around the edges of the rust spots and when scraping gently push towards the center (so you dont spread the rust) and use a rag to wipe it off then take an oily rag and oil the area up a bit and just keep an eye on it and recoat those spots with the rust preventer and it should be good to go
onrust2 years ago
I say, show a picture. It may not be as bad as you think, since you love the car.... I assume. A chipping hammer, Navel Jelly, and a shot of undercoat may just do.
kelseymh onrust2 years ago
Um, I think you mean Naval Jelly, gelled phosphoric acid. Navel jelly is a bit NSFW, if you ask me.
Re-design2 years ago
If the rust extends through, then it's a hole. Have it repaired by a classic car savvy mechanic. It's not something that should ruin a great car.
+1. Almost anything can be safely repaired, by someone who knows what they're doing -- the question is how much it will cost to do the job properly.

Someone who works on classic cars will have more experience doing that sort of reconstruction, so I think that's a very good suggestion. They may charge a bit more, but I'd bet they'll be worth it. Given how many classic car gatherings there are every summer, it shouldn't be too hard to find out who's good in your area.

Have fun with it. My idea of a sexy vehicle is more like an Aptera than like a normal sports car, but to each their own.