I was trying yesterday to raise the rear of my series 2 off the ground in my garage and put a couple of jack stands under the IRS in order to do some exhaust muffler (silencer) putty work. I usually do this by raising each side of the car gradually, alternating every few turns of the jackscrew between the car's own original jack on one side and my Volvo's jack on the other in order for an even rising of the car. (Alternatively, I've also used my son's help sometimes so that we both raise either side at a similar rate–which is faster and a lot less tiring!–in order to get the car more or less level at all times.) With the XJ being so low, you do have to do an awful lot of raising just to put the jack stands underneath even at their lowest notch, so it's important to do it properly. Not heeding my own advice, yesterday I decided to cut corners and go at it the wrong way. (Also unfortunately my son wasn't home to help, so I had to do it all entirely on my own.)
Instead, I tried to raise the car all the way from one side first, then the other without alternating between jacks–it does get tiring after a while, all that shuttling back and forth between sides, y'know. Well, it all ends wrongly that starts wrongly... Even with both front wheels chocked on both their sides each, and with the car listing heavily towards its right-hand side, the split second the right-hand-side rear wheel ALSO left the ground (I was jacking up the rear left first and did not expect this), the car pivoted about the front right wheel, which by now was the car's only contact with the ground (the front left had been the second wheel to leave the ground), moved its rear to the right and away from me and fell hard on the ground, managing to destroy my Volvo jack in the process, which had firmly clawed itself both to the garage floor and the XJ, and for which the sudden, violent displacement under the weight of the car proved fatal.
No harm done, though, either to the car or–most importantly–myself. Except that, as an extra preventative measure, besides the four wheel chocks I had also 'wedged' the front bumper pretty good against a thick set of old tires/tyres that were leaning against the garage wall at the front of the car, so that the car could not move forward–unless it tore the wall down, that is. (I never even imagined a sideways movement of the rear of the car like that!) The thing is that as I gradually raised the rear of the car, the front bumper became ever more firmly wedged between the car and the tires, and as the rear of the car yawed toward its right, the right-hand-side front bumper overrider moved still further into the tires, which–compressed already to their maximum as they were– allowed no further movement in the direction of the wall. (All the flexibility of their rubber had been 'maxed out,' so to speak.)
Not only that, but with the overrider now pressing real hard against the tires, the pressure now allowed for no movement of the overrider whatsoever, and so as the rear of the car fell down and the front went up (with the overrider wedged firmly in place by the aforementioned intense pressure), the right-hand side of the bumper buckled in and down a bit, enough to leave the entire overrider pointing down! The slight buckling of the right side of the bumper is not really noticeable (unless one looks as carefully and intently as a concourse d'elegance judge!), but it tears me apart to see the two front overrriders pointing in different directions now. I tried to straighten the offending overrider up by pulling it upwards using my own bare hands, obviously to no avail.
I was wondering: since it took brute force (the entire inertia or momentum of the car as it yawed and fell) to get to this situation, how about using brute force to straighten things back to where they were at the beginning? If I put a jack stand under the overrider with the car raised on a jack and then carefully lower the car (putting some of the car's weight on the overrider itself for a while, with the jack stand under the overrider supporting that weight), will this do any good or will I end up destroying the bumper and/or the overrrider altogether? Will the cure be worse than the disease?
I do the same thing to raise my XJ on all 4 sides, but I use two factory jacks properly attached to the jacking points, and I raise the front FIRST, keeping the transmission in PARK and the emergency brake fully engaged.
Once the front is raised enough, I add safety jacks to the front suspension, and I lower the factory jacks, then i attach them to the REAR jacking points and start raising the rear until it is Level.
There has never been any movement forward or sideways, to me it sounds like your Volvo jack could not stand the weight and collapsed.
These cars are very very heavy.
I suppose there are 50 ways to straighten the bent bumper but I think what got bent is the Bracket.
Remove the bracket and compare it to the opposite side.
Yago, I'd highly recommend getting a good floor jack, they're very reasonably priced these days. Hard to tell in those pics but it sounds like you need to jack "up" under the over rider with a jack and a block of wood to tweak it back? Like Jose said, it could be the bumper bracket that's bent. In any case a hydraulic floor jack would make it so much easier and safer. We have Harbor Freight here in the states, you probably have something similar. This one has replaced my 2 ton snap on floor jack as my daily go to for anything that's not very heavy. https://www.harborfreight.com/automo...ump-64545.html
It would be a lot safer than using those scissor jacks.
It's money very well spent Yago, although the blue one in the pic looks a bit large (and crude) for the amount of jack. I don't know anything about them, but this company is in spain, https://www.rsf-maquinaria.com/en/ot...r-jacks/gt-20a
and this jack would be much more useable and easier on the back.
Maybe even look into aliexpress, they have the same jacks harbor freight has and at the same prices.
