Replacing jack supports

[Dennis]

Hi all,

still thinking about replacing one of the jack supports without getting outer sill off. I would like to know how the whole thing is put together and whether anybody on this forum has done this before.

I know that the tube is braced by the plate that attaches to the inner sill and that the tube is welded to the inside bottom of the inner sill. Yesterday, when taking of the undercoating (.......fun job), I noticed that just behind the jack support, there is something on the underside of the inner sill that looks like a large welding 'dot'. It's on both supports, so can I assume this is the place where the tube is welded to the bottom of the inner sill (in fact, it's the edge of the floorpan really, but that lines up in the middle of the inner sill it seems).

Now, my question is, can I remove a jack support tube with everything in place by:
- cutting the weld between tube and brace plate (only top side will be a bit more difficult, possibly grind from inside the tube) &
- drilling out the weld spot to the bottom of the inner sill?

Many thanks in advance!!

Dennis

[roblav]

I would advise not doing this. The jack tube is "very" welded to the jack tube support, which is spot welded to the inner rocker panel. The jack tube is also welded to the floorpan. Usually, if the jack supports are no longer structurally sound, then the inner rocker panels are gone too. You could try and cut the welds between the jack tube and the jack tube support, then drill the spot welds between the jack tube support and the inner rocker panel. You really need to assess the condition of the inner rocker panels.
Rob

[Dennis]

Thanks Rob,

it's not so much the support brace that is an issue, but the tube inside. It's very rusted (thru) from the inside. I hear what you're saying about the inner sills, but when the outer sill came off, the inner sill was considered of decent quality still. Bummer that the guys that performed that assessment didn't replace the tube when the outer sill was off......(don't get me started).

Anyway, would it be doable to leave the brace in place, cut/grind it loose from the tube, release the tube from the inner sill bottom and then get the tube out? Or is the tube wider on one end and thus will nut be able to pass through the brace hole?

Forgive me my ignorance, but I guess it happens more often that people need to replace the jack supports, isn't the only difference that I would like to keep the brace in place? If so, is the tube that cut loose from the inner sill from the outside, assuming floor panel stays in place?

Maybe it's a silly idea after all, just want to convince myself that is can/cannot be done.

Any more help is highly appreciated!

Thanks

Dennis

[Dennis]

Did it. It's not too hard as long as the tube is VERY rusted.

Unfortunately you're right, the inner sill seems quite rusty. Now thinking of a way of repairing that without getting the outer sill off.....

Dennis

[Zeke]

I have done the outer and inner rocker thing and there are a lot of connections between various panels at this point. If you aren't too worried about the type of fix you do, you could bond in a new piece with the newer body bonders that body shops use. Many are bonding fender flares in lieu of welding because it's faster, produces no heat warpage and is water tight if the bonder squeezes out all long both edges.

Most won't understand what you have done and will devalue the car when they see the bonding. If you're keeping the car, or plan on a more extensive restoration later on (don't we all ), then hop to it.

Many don't use the jack hole except in an emergency. That's about all you need from it, once in a while use. I really don't care much for those "adaptors" for a floor jack. Puts way too much stress on the body at that point in a cantilever. If you study the Bilstein jack carefully, it puts upwards pressure inside and along the whole top of the receiver. That's how it should be and is less stressful.