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[hoj]

The idler arm was seen by a mechanic I use there was definitely play in it I saw it
Wishbones are coming soon so I'll know when they'redone if its finally sorted

[hoj]

Been told I should get new bolts (pinch bolts)
Anyone know what size please

[05omegav6]

Been told I should get new bolts (pinch bolts)
Anyone know what size please

By whom?

[hoj]

Err a garage

[Andy H]

There are pinch bolts that clamp the ball joints in the bottom of the McPherson struts.

I have changed a few sets of wishbones over the last 15 years and haven't had to replace any pinch bolts.

They have a fine thread - they may be a standard size but I would get them from Vauxhall just to save time.

[05omegav6]

Likewise... only replace if rotten. Same with wishbone bolts...

[05omegav6]

Err a garage

Same garage that failed to spot the knackered wishbone bushes presumably...

Will they be fiiting them as well?

[Diamond Black Geezer]

This came up a while ago, re: pinch bolts. Now, I'm not saying don't change them, in fact I did, purely because I refurbed my front suspension, so all bolts got a nice coat of oem-style silver paint on them. However, in theory, a length of wooden dowel would work as a pinch bolt, the condition of the pinch bolt is possibly the most redundant component on the car's suspension.

Common thought is it is 'holding the front suspension together'. Look at the design of the suspension. If you remove the pinch bolt completely nothing happens. There is a big spring and the weight of the car pushing down, and the wishbone/balljoint wanting to spring upward. If you've ever tried to change a wishbone by yourself you'll know how much aggro can be had in trying to push the wishbone downwards enough to release the balljoint from its home, where the pinbolt sits. The purpose of the pinchbolt is to stop the wishbone 'popping' out of the steering knuckle, but in reality, unless you do lots of rallying, that's not going to happen pootling round town/down the A123.

As said above by Al/Harris... replace only if completely rotten, to the point the wishbone is actually knocking up and down, but I've yet to see that in the last 11 years.

Oh, final - vital - point, please make sure the mechanic nips up the wishbone bolts with the weight on the car, otherwise the rubber bush will tear and you'll be buying yourself new wishbones and paying to have them fitted before you can say 'bad mechanic' 

[Nick W]

There are pinch bolts that clamp the ball joints in the bottom of the McPherson struts.

I have changed a few sets of wishbones over the last 15 years and haven't had to replace any pinch bolts.

They have a fine thread - they may be a standard size but I would get them from Vauxhall just to save time.

If you look at this sort of pinchbolt, the unthreaded portion locates in a groove in the ballpoint. This is necessary to stop the balljoint pulling out of the strut. Using a standard bolt in this design is very dangerous. Even if the bolt is correctly tightened it is still possible for the balljoint to dislodge. I have seen this many times, and there was always further damage.

I haven't replaced the pinchbolts on mine, but I did examine them carefully before refitting them. You're not just looking at the threads, but for wear in the shank or if the bolt is bent.


James, the weight of the car will easily overcome the springiness of the wishbone bushes. Add in a little steering lock, and the assembly will self-dismantle. I've recovered enough incidents like this to know that a ratchet strap around the wishbone and lower spring cup is vital before you even consider moving the car. And even then it's a slow winch job, using as little steering as possible.

[Diamond Black Geezer]

As Nick and Harris say, the issue is heavy wear on the pinchbolt, ie: it's not the same diameter it was new, hence a loose fit, irrespective of how tight you do it.

I think I'm just feeling a bit cautious and whenever I see 'a new pinchbolt' and things similar appear on invoices it's - dare I say it - a way of (some) garages getting a few unnecessary quid on the bill.

Again, as Nick says, if a new pinchbolt is the order of the day, then make sure it's the right one, not just any old nut n bolt. The shank

[Nick W]

I think I'm just feeling a bit cautious and whenever I see 'a new pinchbolt' and things similar appear on invoices it's - dare I say it - a way of (some) garages getting a few unnecessary quid on the bill.

On an Escort, Fiesta or the small Peugeot/Citroens I would order new bolts before starting the job. This is because I've never managed to the Ford ones out undamaged, and have seen far too many French cars with destroyed wishbones after suspension work. The cost of new Escort bolts is trivial at about £2 each.

[Diamond Black Geezer]

Fair enough 

Just seen too many threads of relative newbies to Omegas have, eg: handling issues, get tracking done... then have droplinks replaced, then tracking done again, then new tyres, and so on, before coming here and being given the right diagnosis. Not badmouthing all mechanics, as I say "a way of (some) garages getting a few unnecessary quid on the bill." so not badmouthing the trade as a whole  Hope OP is sorted soon. 

[Andy H]

There are pinch bolts that clamp the ball joints in the bottom of the McPherson struts.

I have changed a few sets of wishbones over the last 15 years and haven't had to replace any pinch bolts.

They have a fine thread - they may be a standard size but I would get them from Vauxhall just to save time.

If you look at this sort of pinchbolt, the unthreaded portion locates in a groove in the ballpoint. This is necessary to stop the balljoint pulling out of the strut. Using a standard bolt in this design is very dangerous. Even if the bolt is correctly tightened it is still possible for the balljoint to dislodge. I have seen this many times, and there was always further damage.

I haven't replaced the pinchbolts on mine, but I did examine them carefully before refitting them. You're not just looking at the threads, but for wear in the shank or if the bolt is bent.


James, the weight of the car will easily overcome the springiness of the wishbone bushes. Add in a little steering lock, and the assembly will self-dismantle. I've recovered enough incidents like this to know that a ratchet strap around the wishbone and lower spring cup is vital before you even consider moving the car. And even then it's a slow winch job, using as little steering as possible.

The clamping action of the pinch bolt needs to be enough to stop any movement in normal use. If there is movement then the parts will wear very quickly.

The location groove is mainly there to align the parts when they are assembled but it does provide a useful last gasp safety net. If there is sign of wear or damage to the bolt then you need to check that the ball joint is still a snug fit in the bottom of the McPherson strut.

[terry paget]

I thought the purpose of the pinch bolt is to ensure the turning motion is accommodated in the ball joint, not in the taper pin in wishbone. I thought it was a fairly high torque nut. What is the torque on it?

[05omegav6]

I thought the purpose of the pinch bolt is to ensure the turning motion is accommodated in the ball joint, not in the taper pin in wishbone. I thought it was a fairly high torque nut. What is the torque on it?

60mn off memory, but might only be 45nm