Rear tyre wear and removing a stuck shock absorber
Discussion
My 92 mk1 Eunos almost passed the MOT today, emissions a bit high (probably due to being sat for 8 months, old petrol and not being warm enough when tested), a leaking shock on the nearside rear, and nearside rear tyre worn.
I pulled the nearside wheel off and it's worn right down on the inside edge, plenty of tread on the outside. The offside tyre is fine.
Would having the knackered shock absorber on this side cause this odd tyre wear, or does the camber need adjusting? If so, how do I adjust it? Looking around the wishbone there doesn't seem to be anything that can be adjusted.
Secondly, any idea how I can remove the shock? The bolt turns, the captive nut is free but I can hold it with a spanner and it is undoing OK, but the bolt is rusted tight into the bush
The shock is undone at the top and the upper wishbone bolt is out, so just this one stuck bolt to remove....
I pulled the nearside wheel off and it's worn right down on the inside edge, plenty of tread on the outside. The offside tyre is fine.
Would having the knackered shock absorber on this side cause this odd tyre wear, or does the camber need adjusting? If so, how do I adjust it? Looking around the wishbone there doesn't seem to be anything that can be adjusted.
Secondly, any idea how I can remove the shock? The bolt turns, the captive nut is free but I can hold it with a spanner and it is undoing OK, but the bolt is rusted tight into the bush
The shock is undone at the top and the upper wishbone bolt is out, so just this one stuck bolt to remove....Can you post a pic to which bolt you mean, is it the 17mm bolt that holds the shock in place on the lower wishbone and the captive nut on the inside of the wishbone as cracked loose and just going round and round?
If so if you look underneath the wishbone you will see an oval cut out,if you elonggate it with a small angel grinder(be careful and but some eye protection on,and make sure it is supported by an axle stand)dont cut right through and not too big.
You should now be able to get a flat spanner on the square not to undo the bolt and remove the shocker.
Put it back together the same way as removal,making sure to pack plenty of copper slip on the nut and thread.
Hope this helps to get her back on the road,
As for the alignment,take it to someone with the equipment to do it,and it will make a big,big difference once done.
Where are you,I use a local place to me for full geos and are very good on price.
Regards
Wayne
If so if you look underneath the wishbone you will see an oval cut out,if you elonggate it with a small angel grinder(be careful and but some eye protection on,and make sure it is supported by an axle stand)dont cut right through and not too big.
You should now be able to get a flat spanner on the square not to undo the bolt and remove the shocker.
Put it back together the same way as removal,making sure to pack plenty of copper slip on the nut and thread.
Hope this helps to get her back on the road,
As for the alignment,take it to someone with the equipment to do it,and it will make a big,big difference once done.
Where are you,I use a local place to me for full geos and are very good on price.
Regards
Wayne
Sorry yes I forgot to specify the bolt - it's the one that holds the lower end of the shock into the wishbone. I can already get a spanner onto the nut at the far end through the gap under the shock, and the nut indeed is undoing OK, the problem is that the bolt appears to be rusted into the lower bush on the shock. I guess whoever fitted it forgot the copper grease...
I'm in Fife about 30 miles north of Edinburgh, but TBH I can't really afford a full alignment atm, I'm just trying to get the car back on the road after a long layup. I'm going to have to fit 2 new rear tyres so if I can adjust the camber of the nearside rear slightly to avoid excessive tyre wear to the inner edge then that would be great for the moment.
I'm in Fife about 30 miles north of Edinburgh, but TBH I can't really afford a full alignment atm, I'm just trying to get the car back on the road after a long layup. I'm going to have to fit 2 new rear tyres so if I can adjust the camber of the nearside rear slightly to avoid excessive tyre wear to the inner edge then that would be great for the moment.
Get plenty of plus gas on it and cross your fingers,it should work loose, if you do the cut out,you can leave the nut on the end of the thread and use a pry bar to help push it back out.
If you look towards the back of the wisbone(inwards towards the diff)you should see the bolts that hold it to the rear frame,two in total one at the back and one towards the front,they should have a big washer with marks on them and a cut out in the middle,spray them both with plenty of plus gas,these will do your camber,but you could do more harm than good if they are not set right.
Regards
Wayne
If you look towards the back of the wisbone(inwards towards the diff)you should see the bolts that hold it to the rear frame,two in total one at the back and one towards the front,they should have a big washer with marks on them and a cut out in the middle,spray them both with plenty of plus gas,these will do your camber,but you could do more harm than good if they are not set right.
Regards
Wayne
Thanks, I will.
I'm not happy about cutting a hole in the wishbone so I'm going to have to resort to drilling and hacking the bottom of the shock collar apart and trying to slice the bush without damaging the bolt.
Last time this happened I hacksawed right through the shock casing to make some room, but this one has a big "Nitrogen inside" warning on it and I don't want to explode myself.
I'm not happy about cutting a hole in the wishbone so I'm going to have to resort to drilling and hacking the bottom of the shock collar apart and trying to slice the bush without damaging the bolt.
Last time this happened I hacksawed right through the shock casing to make some room, but this one has a big "Nitrogen inside" warning on it and I don't want to explode myself.
The hole is already there ,you are just making it a bit wider so you can get a hold on the nut,honest it is the easiest way to do it,I have had to do this loads of times,and if we were on the OC forum ,I could get owners that I have had to do this on their roadsters to post with some pic's.
I am trying to help you with the best way to do it.
I am trying to help you with the best way to do it.
Adjusting the camber might stop the excessive tyre wear but it might not and it might also make it handle really badly. The only way you will know what needs doing for sure is to get the alignment tested properly. Taking a wild guess based on tyre-wear is likely to only make things worse.
Is the bolt protruding even slightly from the bush? If so, get a spanner or something similar underneath the head and around the shank. Lever it against the edges of the recess in the wishbone. You might have to use two, 180 degrees apart to keep the forces even. Use a socket to turn the bolt with one hand, and using the other (or an assistant) try to lever the bolt out of the bush with the spanners.
If it's not protruding at all, turn the bolt by hand whilst emptying an entire tin of penetrating fluid on it. Keep turning for a good 15-30 mins whilst the fluid penetrates if you have to, and just pray that the sucker works loose.
Method 1 worked for my offside rear, Method 2 for my nearside rear. Levering the bottom of the shock up and down against the wishbone might also help, but is much easier if you leave the top mount attached and lever the wishbone itself.
If it's not protruding at all, turn the bolt by hand whilst emptying an entire tin of penetrating fluid on it. Keep turning for a good 15-30 mins whilst the fluid penetrates if you have to, and just pray that the sucker works loose.
Method 1 worked for my offside rear, Method 2 for my nearside rear. Levering the bottom of the shock up and down against the wishbone might also help, but is much easier if you leave the top mount attached and lever the wishbone itself.
The tyre wear could well be down to the knackered damper - often you'll get a feathered or 'saw tooth' edge on the tyre with duff suspension.
So dont touch the alignment bolts till you've got the damper fixed.
RE the bolt - agreed you need Plusgas (proper plusgas or graphite oil is better than WD40) and get it right in there, apply, turn bolt, apply, leave overnight, apply, turn bolt, etc etc.
and if you can get the bolt out a cm or so, then you can get open ended spanners udner the head and use the to pull the bolt while your socket turns it, as already suggested.
So dont touch the alignment bolts till you've got the damper fixed.
RE the bolt - agreed you need Plusgas (proper plusgas or graphite oil is better than WD40) and get it right in there, apply, turn bolt, apply, leave overnight, apply, turn bolt, etc etc.
and if you can get the bolt out a cm or so, then you can get open ended spanners udner the head and use the to pull the bolt while your socket turns it, as already suggested.
The tyre wear could well be down to the knackered damper - often you'll get a feathered or 'saw tooth' edge on the tyre with duff suspension.
So dont touch the alignment bolts till you've got the damper fixed.
RE the bolt - agreed you need Plusgas (proper plusgas or graphite oil is better than WD40) and get it right in there, apply, turn bolt, apply, leave overnight, apply, turn bolt, etc etc.
and if you can get the bolt out a cm or so, then you can get open ended spanners udner the head and use the to pull the bolt while your socket turns it, as already suggested.
So dont touch the alignment bolts till you've got the damper fixed.
RE the bolt - agreed you need Plusgas (proper plusgas or graphite oil is better than WD40) and get it right in there, apply, turn bolt, apply, leave overnight, apply, turn bolt, etc etc.
and if you can get the bolt out a cm or so, then you can get open ended spanners udner the head and use the to pull the bolt while your socket turns it, as already suggested.
Thanks for you help everyone, the shock is finally off after much drilling and dremeling (under the car in a rainstorm 
), managed to get it all out with only a tiny nick in the bolt too so I'm pretty happy. I shall be applying plenty of copper grease when I re-assemble it all.
I shall leave the camber until the shock is back on and I know how the new rear tyre is wearing.
), managed to get it all out with only a tiny nick in the bolt too so I'm pretty happy. I shall be applying plenty of copper grease when I re-assemble it all.I shall leave the camber until the shock is back on and I know how the new rear tyre is wearing.
it's not difficult to adjust the camber, just to measure what you're doing with it!!
the lower wishbone mounts onto concentric bolts which change position as you rotate them. so simply put, moving both front and rear mount inboard (i.e. effectively shortening the lower wishbone) will reduce your camber. this will give you a quick fix until you can get it properly checked but you risk messing up the rear toe at the same time as it's obviously adjusted by the same two bolts.
the lower wishbone mounts onto concentric bolts which change position as you rotate them. so simply put, moving both front and rear mount inboard (i.e. effectively shortening the lower wishbone) will reduce your camber. this will give you a quick fix until you can get it properly checked but you risk messing up the rear toe at the same time as it's obviously adjusted by the same two bolts.
skinny said:
it's not difficult to adjust the camber, just to measure what you're doing with it!!
True but adjusting camber alone without knowing what the toe & caster are doing might just be making the problem worse rather than better. A wheel can have a lot of camber and still be flat on the ground & wear evenly if there is enough toe-in to match. My car is set up with a bit more camber & toe at the rear to give extra traction (at the expense of increased tyre wear).If the camber is that far out that it destroys one edge of the tyre but the other edge still has meat on it on one wheel and the tyre on the other wheel is fine then you should be able to see it out by viewing the car from behind. It'll look kinda like /---|
nah he'll be alright, camber has a bigger effect on uneven wear than toe. just make sure it's not pointing out towards the front by putting a big straight stick across the tyre 
in any case, i'd still drive a bit carefully until you get it properly sorted as it will likely handle fairly unpredictably.
in any case, i'd still drive a bit carefully until you get it properly sorted as it will likely handle fairly unpredictably.
Once I've refitted the new shock I'll attempt to measure which way the rear hub is pointing, it might be pretty obvious with a long straight edge clamped to the disc. If I can see an obvious problem I'll tweak it a little but otherwise I'll get a proper alighment done at some stage.
The car has always handled nicely and never tried to spin out, even in heavy snow (it appears to have a working LSD which helps) so I don't think it's setup in a dangerous way, but people always state that a proper setup transforms the handling so it's worth doing at some point.
The car has always handled nicely and never tried to spin out, even in heavy snow (it appears to have a working LSD which helps) so I don't think it's setup in a dangerous way, but people always state that a proper setup transforms the handling so it's worth doing at some point.
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