Front wheel rubbing wheel arch

[Jakko]

My S3C front offside wheel rubs the inner wheel arch when the nose drops under heavy braking or on hard left lock. After traveling back from SCH I measured each side and have 20 mm difference in the front ride height. About 160 mm offside and 180 mm nearside. these figures look compatible with the suspension wicki. I have taken other measurements as follows. Length of thread under the lower spring cups varies by 3 or 4 mm. Spring length with car on axle stands and wheels removed varies by a similar amount. I cannot identify the type of spring/shocks fitted (no labels), but they are adjustable for height and rebound rate.

The units look to have been on the car some time, but was advised at SCH that they are not the original parts.

I intend to raise the offside ride height a little ( when I can get hold of a C spanner) as an interim fix and have a closer look in winter. If any of you have any further advice I would be grateful.

Met some of you at SCH, but not enough as I had to leave early. Great day though!

[Griffinr]

Start by getting some releasing oil on the adjuster rings while you source the C spanner. I would also check all the joints and bushes for wear expecially on the lower side as any wear hear is magnified by the suspension angles.
Rob.

[tvrgit]

What brand of shocks are they? The plastic bushes in my AVOs wore away badly (quite common according to other threads at the time) and that would seriously affect movement under braking.

Also check that the arches are fitted as high as they will go, and also tucked as far forward (round) into the front of the arch as you can shove them - I ended up drilling new holes in the plywood bonnet bracket, about an inch forward, to move the arch as far from the tyre as it would go.

[tvrgit]

What brand of shocks are they? The plastic bushes in my AVOs wore away badly (quite common according to other threads at the time) and that would seriously affect movement under braking.

Also check that the arches are fitted as high as they will go, and also tucked as far forward (round) into the front of the arch as you can shove them - I ended up drilling new holes in the plywood bonnet bracket, about an inch forward, to move the arch as far from the tyre as it would go.

[Jakko]

Just trawled through my history file and found receipts for replacement AVOs in 2007, so I expect that is what is still fitted. The wheel arch seems to be firmly attached, but will check it again. Will also look closely at the lower shock bushes. Thanks for the responses so far. All good stuff from the forum as usual.

[chiefyo]

Hello Jakko. Apologies if this is stating the obvious - But when taking any comparison measurements for chassis I would suggest you need to compare like for like on either side of your front suspension , basically measure from a flat surface to any identical point on either side of your front suspension take as many different measurements as you wish and compare these. What you are achieving by this is checking suspension height without reference to body. Depending on what your measurements tell you. You can then hopefully get closer to your problem. I.E if chassis heights match then problem is in the body somewhere. You can also do something called a drop test to check for chassis twist or damage . But thats another story. Hope the above makes sense

[Jakko]

Chiefyo, Thanks for your reply. I forgot to mention that my ride height measurements were from the same chassis point at the front corner on either side. I recognized the risks of variation using body points. I will take more chassis measurements tomorrow to capture more data and report anything Ibthink may be diagnostic.

[Jakko]

By way of an update, I wound the spring seat up one turn on the offending side to try it out. Then went for a lovely day out to the lake district. Net result is the problem seems worse now. Does it make sense that putting the spring under greater compression lowers the ride height? Seems counter intuitive to me, but hey, I'm still learning.

I have found other issues during my investigations (funny old thing). The bonnet is lower on one side and slightly off centre, both issues will be adding to the problem. I also saw some apparent softness in the shock absorber bushes, but am not sure what good looks like. Shocks are AVO,s so will try to find replacement rubbers to add to my winter list. (See separate post)

[QBee]

1. You might find you need two C spanners if your locking ring is siezed
2. Its the correct way to raise the ride height
3. Ride height was the reason why I had wheel arch rubbing issues for months - I thought of everything else before the penny dropped
4. If the dampers have a small adjuster near the bottom, you might try tightening them (turn clockwise) to see if it helps with the nose dive. Too much and the ride will be ste. Fully tight and the front still bounces like a tart on a Saturday night, your shocks need a replace/refurb.

[QBee]

Jakko said:

By way of an update, I wound the spring seat up one turn on the offending side to try it out. Then went for a lovely day out to the lake district. Net result is the problem seems worse now. Does it make sense that putting the spring under greater compression lowers the ride height? Seems counter intuitive to me, but hey, I'm still learning.

No, you are right, raising the wotsit with the C spanner raises the ride height. Did you have any ballast in the passenger seat for a change? I found a lawnmower in the boot dropped my rear ride height by 9mm, and it was only an 18 inch Honda. Imagine what a 68 inch Shoe Collector can do to your ride height?

[greymrj]

Again, it might be stating the obvious but have you checked where the wheel arch is touching and then checked the clearance on both sides? On mine the offside wheel arch was formed differently to the nearside and the clearance was much less. Not only did the wheel touch at one point on big bounces, but it also touched at another place on full lock. Checks showed clearance to the wheel, at exactly the same ride height at the chassis outriggers, differed by almost 30mm! This winter programme includes taking off the offside wheel arch and remoulding it correctly! Mine is an earlier car and the arches are a little different but I believe this also occurs on late cars. At least one owner of a later car has worn clean through at offside wheel arch but hasnt got a problem on the nearside.

[paul.deitch]

Front wishbones parallel to ground and equal, rear rails 10-15mm higher was the recommendation from my supplier. I found those settings pretty good. I originally had the same problem as you. Good luck.

[Jakko]

Paul, thanks for your comments. I have checked the front wishbones and they are not parallel to the ground, even on my nice flat garage floor they are higher at the wheel ends by around 8mm. I measured the angle (roughly) and it is about 4 degrees from horizontal. (one more than Diana Ross. This means that the inboard chassis rails are effectively lower than optimum under your guidelines.

Chassis height at the front outboard corner differs by approx 20mm (157mm and 176mm) and spring lengths vary by 5mm (160 and 165mm). I find these measurements are somewhat confusing.

I am more interested now in how to adjust my shockers to get a suitable ride height. I intend to try to get some new shock bushes as a first pass. I don't want to spend hundreds on new shock unless I have to. However, I suspect my springs may have sagged as they look quite compressed as they are currently set up.

I know the bonnet is not adjusted correctly. Offside is lower, which probably accounts for most of the rubbing and I will address this over winter. When I insert my hand under the wheel arch there is a pronounced difference in clearance between the tyre and bonnet arch.

Is there a noddy's guide to setting up the front shocks to help me out? Comments on a postcard please to "Confused Jakko @ hopelessly lost.com."

[greymrj]

Are you sure exactly where it is touching? Is it the section of wheel arch attached to the bonnet or the one attached to the body? It appears that the latter is usually the problem.

[Jakko]

With mine it is rubbing on the one attached to the bonnet. There are clear witness marks showing the area being rubbed.

[Le TVR]

Jakko said:

However, I suspect my springs may have sagged as they look quite compressed as they are currently set up.

That is the usual problem. Car is mostly driven with driver only and will tend to sag on that side as the springs have compacted.
If you have 20mm assymetry under the front outriggers, do have similar assymetry under the rears? ie is the chassis still straight.

Unfortunately it does sound like its time for new springs, shocks and shock bushes. Maybe even check the ARB bushes at the same time.

[v8s4me]

If you jack up the front end maybe you could back off the adjusting rings until the springs are loose. You could then measure their free length and see if you sagging theory is correct.

[Jakko]

Thanks Joe, I like that idea. I have temporarily wound the offending side up a couple more turns and will take it for a quick (long) run later to see if this helps. The more I look at the shock bushes, the worse they look. I think it's inevitable that £££££s are going to have to leave my plastic.

[Le TVR]

Usually both front and rear sprngs would sag on the same side.
Might be an idea to wind up the rear spring on the same side by the same amount or the corner weights will be very unbalanced?