6 replies to this topic

[new_van_man]

Hi,

I have just finished rebuilding the mini from scratch. Theonly thing i did not take apart were the driveshafts and hubs (front).

Since I have been using the car there has been a rather odd sort of knocking knoise when teh drivers wheel goes over bumps in the road. It only happens on the drivers side.

I have jacked the car up and everything looks and feels secure. What could this be? Suspension arms tight, track rods not bent, steering rack secure, subframe mounts all good.

The noise is like a banging or knocking but only over bumps, on motorway at 70 its fine (when clutch depressed so low revs no klnocking noise)

The other rather weird thing is the steering. The steering never seems to set itself to zero (i.e the steering wheel is not straight when wheels are. Then if you go round a sharp left turn quite hard the steering wheel then goes how it should be in a forward driving position when driving wheels are straight. Go round a right turn sharply and the steering wheel returns to an offset postion when the wheel are opointing stratighht again.

The steering rack does not appear to have any play in it and the wheels move in relation to the steering wheel. i.e steering wheel moves so do the wheels with no play.

But why wont the steering wheel return to the same position depending on which way you turn.

Apart from this the car is awesome!

Any help much appreciated,

Cheers

[tiger99]

It is hard to diagnose things like this, sometimes even when you are in the car, and always from a distance, so I could be completely wrong. And, you have checked the prime suspects. But I will suggest some possibilities, although you may have checked these already.

Firstly, are the ball joints in good order and properly shimmed, with the anti-rattle spring in the lower joint? (The lower joint loses its vertical load sometimes during suspension movement, the spring is there to keep it tight).

Second, badly worn knuckle joint. Probably unlikely as the car would sit low, unless you have HiLos.

Thirdly, shock absorber bushes, or the large washers not correctly fitted, possibly allowing metal to metal contact during suspension movement. Or an internal fault in the shocker?

Fourth, and I have never, ever heard of this happening, but it is theoretically possible. Loose bolts in the shock absorder to body mounting bracket, they may seem tight but it may shift under dynamic load.

Fifth, worn lower arm and/or tie rod bushes allowing metal to metal contact. You will have checked those already, but if they get oil on them they can deteriorate surprisingly quickly, and may make the steering feel squidgy.

Sixth, worn hole in subframe where lower arm pivot bolt locates. It locates in three places, and only one is held tight by the nut, the others being a good push fit in the subframe.

Seventh, upper arm bearings, or too much end float.

Eighth, worn or missing rebound stop. the knuckle can become unloaded on droop, and may even become disengaged. Or rubber cone spring may rattle against inside of subframe tower, or knuckle in end of trumpet.

Or maybe a loose component in the braking system, which should go away if you apply the brakes lightly.

Totally wild guess, something that should not be there rattling about loose in the trumpet....

I think you may need to do some small amount of dismantling for a closer look and feel of various bits. Good luck!

[tiger99]

Oops, I missed one thing you said. The steering not returning to the same centre position is a very big clue. Normally loose rack U bolts, but you have checked these. Or subframe mounts, but you have checked these. However, the rear lower mounts often fracture (rubber seperating from metal) and because they are held in place fairly tightly, may look all right.

That leaves lower arm bushes as prime suspect, assuming the shell or subframe are not coming apart at the seams.

[new_van_man]

Tiger,

Thanks for your posts on both my issues. First off the lower arm and top arms were fully rebuild with new bushes and pin (lower arm), and top arm had a rebuild kit. Have hi lo suspension fitted but at slightly higher than standard ride hieght with new knuckles. The hi los are not genuine, is possible the cones are moving around (i think this very unlikley).

I havnt taken the rear subframe mounts off to have a look and the old ones were reused. So they could be the culpritt. When i brake i can feel a sort of banging sensation if teh clutch pedal is depressed at the same time. the noise is definatley coming from the drivers side. I will try and take these off and have a look, i take it that it is hard to see when on the car as under compression will hide any defects.

I will also check the steering rack bolts again, but they were tight last time i checked.

Cheers,

Ed

[spiteri87]

having same exact same problem well be defo using this advice

[R1minimagic]

Sounds like the rear subframe floor mounting, i would also check the subframe at the rear where the large holes are, for cracks (common problem when the rubber mounts are shot)

Also, lift the carpets and check the floor isn't cracked.

[tiger99]

One more thought, could it be the engine steady bar? It is on the drivers side, which is my only reason for suspecting it. But as you know what you are doing and have already replaced all the obvious things, I expect you have checked that too.

This is going to be something very odd, I think, but hopefully trivial to fix.