15 replies to this topic

[Club man]

Hi all, been for Mot today and when the chap jacked the rear up one wheel stayed up and the other dropped down, we where unsure which was correct and thought maybe a shock is to blame, any ideas anyone?

Thankyou

[tim-d]

Dampers shouldn't be the issue here - they'll just stretch to the extent of their travel pulled by the weight of the rear arms, wheels etc. (one daft possibility is that you've got mismatched rear dampers fitted - perhaps one meant for a lowered car???). With no weight on it may look a bit odd but if it was performing ok beforehand then there shouldn't be a problem, unless the problem persists when the car is back on its wheels - my guess (and it is just a guess) is that the balljoint on the end of the ally trumpet has perhaps popped out of it's socket and not realigned to go back in - unusual with dampers on but not impossible - certainly if suspension cones are knackered...

Testing dampers not possible with them on the car, check for fluid loss or evidence of leaking - easy to pop them off pump by hand a few times and compare respective resistance.... Std ones are peanuts so if they're old just replace if in doubt...

[Cerberus]

You can check the dampers when they're on the car. This is exactly how I found out mine were shot.

Jacked the car up on a two poster ramp, the wheels drop, and the dampers slow the dropping if they are working correctly.

On mine, one just dropped straight down, and you could lift the wheel up and down with one finger. The other was slightly better, and the wheel didn't drop as quickly. When they were removed, you could pump them with ease as there was basically no fluid left in them.


With regards to the OP, it could be that one damper is stuck. How much of a difference between the two heights was there?

[tim-d]

You can check the dampers when they're on the car. This is exactly how I found out mine were shot.

Jacked the car up on a two poster ramp, the wheels drop, and the dampers slow the dropping if they are working correctly.

On mine, one just dropped straight down, and you could lift the wheel up and down with one finger. The other was slightly better, and the wheel didn't drop as quickly. When they were removed, you could pump them with ease as there was basically no fluid left in them.


With regards to the OP, it could be that one damper is stuck. How much of a difference between the two heights was there?

Yep spot on forgot that one!!!

[lrostoke]

Could even be a seized radius arm pivot shaft..

Undo bottom shock fixing see if arm is free to lift up and down.

[Club man]

Thanks for replies it's jacked up at home now, one shock is at full extend and really easy to lift wheel and the other side hasn't really dropped at all and is quite stiff to move the wheel up and down.

So as suggested I will replace the pair as I think they prob have both gone, just in different ways, then when there off I will do what you have said then check how the arms are sitting then, and check those trumpet joints and pivots

Thankyou for helping

[Cerberus]

good time to check your cones too.

[JustSteve]

The knuckle joints are not the problem, and its highly unlikely that the dampers have had it..

It's most likely that it's the pivot spindle- the spindle and bush/bearing are probably both trash. It's easiest to buy a new reconed radius arm.

Might as well replace as a pair, and take the time to service the rest of the suspension. (Cones, knuckles, dampers).

Out of interest, when was the last time you greased the radius arm pin?

[bmcecosse]

The test described up there ^^^ is NOT reliable test for dampers (not 'shocks') - they really need to be removed from the car - but if the back of the car bounces about - well - make your own judgement. The problem is almost certainly a seized up radius arm........

[Cerberus]

The test described up there ^^^ is NOT reliable test for dampers (not 'shocks') - they really need to be removed from the car - but if the back of the car bounces about - well - make your own judgement.

Why not?

The damper is supposed to damp the movement of the wheel/suspension in the vertical direction. If when the weight is taken off the wheel, and it just drops to full droop straight away, and can then be lifted up and down with ease, then the damper is not working (or it's a very very soft one).

I agree it may not be the shocks, but I'd say it's as likely as a seized radius arm, especially if they're the original shocks.

[Carlos W]

Did it fail the MOT?

[Club man]

Hi, they have been greased at fairly regular intervals and when I do it it won't take alot before comming out, it's all jacked up and I'm going to move the tank later to get the dampers off so should be able to asses the arm

Yes it did fail the Mot although he didn't know what to put down as the fail because he was unsure where the problem is and picked somthing generic from a list about suspension components and put it down as the loose side rather than the stiff side

Thankyou, will keep you posted

[Club man]

Ok, so I removed the dampers today and they seem fine, i managed to get the side where the arm wouldent drop to move but noticed that the nut on the outside of it where the grease nipple is moves with it so I'm assuming this is the fault.

I loosened and re tightened the nut and pumped new grease into it and pushed alot of the old grease through but the nut still moves with the arm so I'm assuming its had it?

Thanks

[JustSteve]

Yup, exactly as I thought... Don't bother nessing about getting a repair kit, and finding somebody able to ream the bushes, ring up somebody like minispares and tell them you'd like a refurbed set... Fit nice new clear ones, and send them your old rusty FUBARed ones... Done!

[Ethel]

Press the pin out. It's only supported at the ends, so a bit of to and fro should expose enough of the pin to see where it's seized.