Looking for some input here, please.
 
I am having an issue with my Capri where it drives fine until about 70km and then the steering gets a really pronounced wobble. It comes up through the steering wheel and you can barely hold the car in a straight line it is so bad. Once it starts it keeps happening until you slow down quite a lot and is then fine again. Doesn't seem to make any odd noises or other tells.
 
The car has had a professional wheel alignment (Monaco Performance for those in the Newcastle area), wheels are in balance, tyre pressures are good. Everything is in specification and looks fine.
 
The front suspension has eccentric strut stops (the bearing ones, no bushing) and adjustable lower arms all from SMCKA, adjustable coil over conversion and the sway bar is some Mark Delaqua thing he supplies for V8 conversions and is running anti dive arrangement with three double bushes.
 
Advice appreciated.

Any minor slackness in any component can cause wobbles. .. Even if the alignment is set right. Start at the wheel brgs then move inwards thru all the bushes(steering rack mounts are the usual culprit), all balljoints and even the rack itself. . Don't forget the flex coupler to the column . Jack one wheel off the ground and use axle stands so you can get a decent length strong plank or rhs bar under the tyre , borrow a friend to lightly lever the tyre up and down while your checking the moving parts. . Feel for looseness and minor knocks etc . Next is get ur mate to turn the steering slightly L to R to take up the slack play so you can see/feel the steering moving , if nothing is loose go back to the alignment shop and show them... They might adjust the toe outward out inward to compensate it.

Good luck !

Does it go away if you apply the brakes?  Could be bearings..
 
 

wattsy I had the same as you described, it was at about 70 as well.
After rebushing everything, mine was the steering rack plastic/nylon cup bush in the rack. From memory it is opposite where the pinion goes in, inder the inspection plate. Sorry it was done around 20 years ago, then I also filled the boots with the recommended volume of oil, after that I had Beurepairs do a wheel alignment, and they lost all of the fluid out of one boot.
 
hope that helps.

Cheers for the replies. I have been doing this thing so long it gets hard to recall what has been done and what hasn't. From memory the rack was a reconditioned one but I was a bit suspicious of play on centre.

Do the boots not get filled with grease? Never seen them with oil. Does it go away if you go faster.

i'd never seen anything done with oil before either, but that's what the workshop manual (green Haynes?) had in it.
Ithought it might have had a dampening effect, but of course if the boot ties came loose you lost some.
 
my vibration came and went depending on the speed, you could accelerate past it.
I thought this was a generally common fault?

Check that the centre hole of your wheels actually fits the hub, you can get reducers to make them tight.  
Next check your stud holes in the rims in case they are flogged out.
Check the wheel nuts are suited to the type of wheels you have some are tapered some have a mushroomed end
Check rack mounts are not cracked allowing rack to move left and right (have someone wiggle rack while the wheels are on the ground)
Rack ends have a tendency to wear out
Play in the rack is adjustable by shimming
keep searching something will turn up, most likely wheels or rack itself if everything else is new

Can anyone please list the ID/OD size and thickness of the washers on the sway bar/control arm bush please? I need the sizes ASAP as my originals were lost at a shop and I want to swap the dodgy ones I have for better ones. Thanks in advance :)
 
I think (hope) I have found the cause of the wobble. The yellow bushes where the control arm meets the cross member haven't been in the car more than a few years and have driven almost nowhere. The holes in the middle are now all oval and sloppy. New bushes on the way.
 

jaysus, that will do it alright.