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MG MGB Technical - Compressing rear springs

'72 Roadster - Just refitted the rear axle and springs. Everything went fine except that now it's all together, with the car supported by axle stands under the axle, neither the check straps nor the link arms can reach their fixings by some 2". The car is basically still stripped down so no tank, seats, gearbox, engine etc., so very little weight. I noticed that the rear shackles are nowhere near vertical, although not jammed against the chassis member. Perhaps all I need are a couple of friends in the boot for ten minutes. Perhaps there's a jacking method one of you guys has used?
Any thoughts?
Richard Coombs

Do you have new springs? They typically have too much arch.

Tom
Tom Custer

With no engine or gearbox there isn't going to be enough weight in the car to compress them normally. Unless you can jack the body *down* against the roof (!) you are going to have to use weight in the boot.
Paul Hunt 2010

The springs are about 3000 miles old.
Looks like it'll be friends in the boot then.
Richard Coombs

Just confirmation for future reference, two friends and a wife in the boot is the going weight for compressing the rear springs enough to get the rebound straps connected. A guess at the weight would be about 450lbs.
Richard Coombs

You could rope the front wheels/axle of the trolley jack to the body of the car, and jack up the spring. I've done this when I was checking shocker travel after I lowered the car, but take great care and make sure the rope is strong. If it lets go you could be in trouble.
Mind you, I hope your rubber bounce straps are strong, they might tear under that much tension.
Peter Sherman

They are *supposed* to be able to take the shock of the axle and springs when a bump throws the wheel of the ground, so they jolly-well ought to take the standing load! Mind you, with current poor quality production of so much stuff these days who knows? I replaced my V8 springs recently, the straps looked a bit ratty so I replaced those as well. The new ones showed no sign of the 'string' reinforcing that the old ones did, and I noticed they stretched almost an inch when taking the load of the axle and spring. Unfortunately I didn't note how much stretch there were in the old ones before I took them off, it wouldn't surprise me if it had been virtually none.
Paul Hunt 2010

Good points Paul. My straps are the old 'stringed' variety and show no signs of stretch or tear.
Richard Coombs

This thread was discussed between 30/06/2010 and 12/07/2010

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