7 replies to this topic

[Pickup]

Hi,

sometime over the last few weeks the right hand rear corner has dropped by about an inch there's a a light knocking noise from the right hand rear - (which wouldn't bother me but it turns into a grinding noise :'( going over bumps and round corners). I had a quick look tonight - the brakes needed adjusting anyway - and it looks like the trumpet is a bit loose (at the knuckle end).

Any ideas as to what the problem (and the fix) might be?

Thanks

Fraser

PS the rear subframe & suspension was replaced about 2 1/2 years (22k miles ago) and I believe that the ride height was altered because it had been set too high - I think this "alteration" involved a hacksaw and some large washers but no-one's admitting to anything.

[Dan]

There's no way to set the ride height too high unless you have adjustable suspension.

Probably your cone has collapsed. Or if you adjusted the rear ride height by cutting the trumpet with a new, standard cone the spring has just settled as they always do and the trumpet is no longer long enough to do the job. Mini's are meant to be higher at the back than at the front. Cold also be the knuckle cup but it sounds a bit too extreme for that.

[Sprocket]

Didnt the van and pick up models have a slightly different radius arm with a slightly longer lever action resulting in a stiffer/higher suspention at the rear. For carying the extra weight??

If the trumpet has been cut by hand with a hack saw, id suspect the knuckle has now worn or worst case cracked the trumpet causing it to come loose. Either that or the nylon cup has worn through.

I found that the grease used in these knuckles, strait out of the packet is not at all, any good. I replaced the knuckles july last year for new ones, stripped and cleaned them two weeks back and the grease had gone hard and there was nylon on the knuckle itself very little of the grease that was left in any state to lubricate the joint was no where near it.

or it could be a seized pivot arm and has now worn the subframe

[Pickup]

Thanks for the replies,

it's actually a saloon, the radius arm is free to move.

When the car got the new stuff fitted it was sitting high at the back (about 4 inches between the top of the rear wheels and the arches). The guy that did it said he could adjust it took the car away and brought it back later that day with it sitting much lower.

F

[minislapper]

The radius arms are exactly the same. I was once told that the trumpets were a slightly different length but was never convinced there was any truth in it.

The only way you are going to find what the problem is, is to strip it down and check all the components and replace as necessary.

On one of my previous minis, the ring on the donut had rotted away causing it to sit on its ar$e. I'm sure it will be nothing too serious. If parts have worn out on one side, odds on they will do the same shortly on the other so often best to replace both sides.

It doesn't take much to make it sag pretty badly at the rear as the ride height ratio is, I think, 1:5, as opposed to 1:3 at the front so even a minimal drop makes a big difference.

[Dan]

Take it right back to whoever butchered it (assuming it was a garage not a mate) and complain. What he should have told you was:
'Wait three months at least before you decide on any changes to the ride height as new springs will settle dramatically especially at the rear (for the reason above), even disturbed used spring will settle for about a week."
And Sprocket is right that if the trumpets were badly cut they could be tearing at the nose under the load.
As I said, it's meant to be higher at the back. That's how it's designed and its part of the suspension.

LWB Minis do indeed have longer rear trumpets than saloons. Actually vans and pickups do, don't know about estates.

[Pickup]

Thanks folks,

Will try new (well different) trumpets & donoughts this weekend (hopefully). I'm still a bit confused as to why it's taken 2 1/2 years & 22,000 miles to "settle"??

[Sprocket]

Just thinking now. maybe the longer knuckles have been fitted??

And like i said, less than 12months and the grease was dry and the knuckle had plastic on the metal.

Let us know what you find