21 replies to this topic

[KJM]

Model:1979 Mini Special

Description of problem (please be as in depth as possible):

Hi everyone, I have just taken the mini for it's first MOT in years and it failed on a few minor things.
The inner joint of the steering arm has too much play apparently -easy I thought... I'd change the track rod... until I tried looking for one and they don't seem to be available. I pulled the steering gaiter off and it seems that the track rod is part of the steering rack (the ball joint part doesn't have a hex head on)

My question is whether I can replace just this part or is it time for a new rack?

Also, the lower ball joint on the lower arm failed as it hass too much play - the mot guy seems to think that removing a shim will sort remove the excess play it has - anyone heard of this?

And one more thing whilst I think of it... the hydrocarbons were too high, they reckon that I need to retard the timing (it runs on for ages after keying off!) Is this something that could cause this?

Any help appreciated (especially as I'm on a tight time limit due to retest!!)

Thanks,
Kieran

[oltonlad]

i dont understand why u cant replace the track rod end, i've got a mini special and the rack on mine is the same as any other mini that i've owned, as far as the ball joints are concerned you may as well replace it as u have got to strip it down to shim it anyhow and theyre really cheap to buy, i would take a closer look at the rack or post some pics if possible so we can see exactly what you mean, retarding the timing may help with the hydrocarbons as will gapping the tappets a bit wider until it has been tested.

Edited by oltonlad, 03 May 2011 - 08:03 PM.

[Dan]

He's not referring to a track rod end. He has wear in the inner end of the track rod, the ball joint on the end of the rack itself.

The rack is designed to be non serviceable outside a reconditioning facility, replacing a rod and servicing the joints means finding some parts that are hard to track down from normal suppliers and will have to be traced through engineering firms. Then driving out the pin that seals the ball joint and rebuilding it. Keith Calver has started making kits to overhaul the rack and leave it with more easily serviced, better joints that can be rebuilt in place. A replacement rack is the easiest option though.

Running on is caused by something in the combustion chamber getting red hot. This can be any of a number of things for a number of reasons. Timing is a possibility, but there are many more and a lot of them would also alter the tuning. The engine needs a good service and tune.

[icklemini]

The inner joint of the steering arm has too much play apparently -easy I thought... I'd change the track rod... until I tried looking for one and they don't seem to be available. I pulled the steering gaiter off and it seems that the track rod is part of the steering rack (the ball joint part doesn't have a hex head on)

Try your local factors - do quite a few track rods to be honest, they can be done in situ, however you need pipe grips or the special tool to undo the knuckle...

Considering the price of a new rack for a Mini... it would be cheaper to buy a new one however...

[Big_Adam]

Also, the lower ball joint on the lower arm failed as it hass too much play - the mot guy seems to think that removing a shim will sort remove the excess play it has - anyone heard of this?

If you not had them done for a while, I'd change them. I tend to go with a system of change > shim > change. Many people will tell you to replace regardless, but I'd rather reshim if the balljoint isn't too old.

But if you never had them done / don't now when they where last replaced, I'd replace. Its £10 bits and can be done on car (its a pain, but can be done).

[MRA]

It is better to replace, however make sure that you lap them in to the seats and cap nut, this will give your ball joints a longer smoother life, the issue with shimming them is one of safety not cost.....

I would like to run a survey on those Mini owners that have had a broken ball joint shortly after it has been "re-shimmed" unfortunately I know that not all of them are in a position to respond

[KJM]

It is better to replace, however make sure that you lap them in to the seats and cap nut, this will give your ball joints a longer smoother life, the issue with shimming them is one of safety not cost.....

I would like to run a survey on those Mini owners that have had a broken ball joint shortly after it has been "re-shimmed" unfortunately I know that not all of them are in a position to respond

Thanks for all your replies - for some reason my e-mail notification didn't work so I've only just realised!

I think I'll just have to buy a new rack then, it seems a bit silly that you can't replace just the track rod though!

With regards to the ball joint, I do have a new kit to put on, but I'm a little confused with the shims - do I put one on and feel how much play there is and adjust to suit, or do they need "x" amount regardless? And by lap them, do you mean with lapping paste as you'd do a valve?

Thanks!

[MRA]

It is better to replace, however make sure that you lap them in to the seats and cap nut, this will give your ball joints a longer smoother life, the issue with shimming them is one of safety not cost.....

I would like to run a survey on those Mini owners that have had a broken ball joint shortly after it has been "re-shimmed" unfortunately I know that not all of them are in a position to respond

Thanks for all your replies - for some reason my e-mail notification didn't work so I've only just realised!

I think I'll just have to buy a new rack then, it seems a bit silly that you can't replace just the track rod though!

With regards to the ball joint, I do have a new kit to put on, but I'm a little confused with the shims - do I put one on and feel how much play there is and adjust to suit, or do they need "x" amount regardless? And by lap them, do you mean with lapping paste as you'd do a valve?

Thanks!

The main reason why you can't buy the parts anymore is because of safety, buying parts for an item and then fitting them incorrectly is very dangerous how do you inspect a rack for wear ?

The only real way is to remove it from the car, strip it down, inspect ALL of the parts and replace were necessary then rebuild.

What was happening was that the old rack was left in the car (so was never really checked) and new track rods fitted when they wore out, so any wear within the rack itself went unnoticed

A recon rack is about £30 upwards dependant on quality....

The only downside to fitting a new rack is cost can be a little higher
The only upsdide to a recon rack is cost is lower.

Fitting ball joints (swivel pins) is a process of iteration, how you do it is up to you... ie if you add a shim and it's too tight, you add another.... and so on when it gets too loose you remove one and so on, till the movement is just right.

The movement is really difficult to describe on a website, but primarily it needs to be smooth in operation, not loose, if it moves on it's own accord it is far too loose, if you need a bar on the end too move it it is too tight, however we being humans, are all different, some people are stronger than others etc...

I find that fitting a ring spanner over the end works for me, I can feel how smooth it is and how easy it is to move.

Lapping in the ball joint, yes this is done with fine grinding paste only and no electric tools, using electric tools will simply cause it to fail due to hot spots, which are high spots that have been overheated,

You may think that if you are very slow it won't casue an issue, however the infinately small contact patch having a reasonable energy exerted on it will overheat locally

***EDIT*** I have corrected my mistake with the shims, I mixed up loose with tight, the above information is now correct.

Edited by mra-minis.co.uk, 05 May 2011 - 09:39 AM.

[KJM]

Ok thanks for your help! I'm going to look into prices for racks, and have a go at the ball joint - this might seem a silly question but do you check the "tightness" of the ball joint bolted tight to the lower arm or just hanging off the hub and checking purely the movement of the ball?

The other slight query I have (which I'll find out when I do it) is that the guy who did my mot said that I will need to REMOVE a shim to make it a bit tighter, rather than install one which is contradictory to what you said. Obviously you work with Minis all the time and the MOT bloke doesn't, so I will go with what you say!

Thanks again for your help!

[MRA]

My mistake, thanks for highlighting it for me Have now corrected it...

Although I suspect that the MOT man was on about removing to tighten an already installed but loose ball joint, this is very bad practice and should never be undertaken due to the high possibility of a fatigue failure.

[midridge2]

you could do it the mra way or do it the correct way the mechanic has told you, i know the one i would do to get it correct. lol

[KJM]

Hmm yeah i think the "correct" way will be done... I have a new ball joint kit anyway so it'll be silly not to use it!!

Cheers!

[MRA]

you could do it the mra way or do it the correct way the mechanic has told you, i know the one i would do to get it correct. lol

Are you referring to my mistake with the shims above ?

[midridge2]

i was, but by the time i had typed out my reply and had a coffee you had changed your posting.

[MRA]

A quick cover up .....