AK, unstable and not self centering properly

[daleb]

Hi

I have an 02 AK , jag XJS based, 5.7 chevy which stopped self centering when I renewed all the ball joints on the front. As far as I remember there were no shims to install as the joints were self contained and did nto have grease nipples. It does seem to be improving as I get more miles on it.

How do I measure castor. Ride heights are set up as per AK's instructions using spring preload and typical driver passenger.

And brakes. It was pulling left under braking and I found the Drivers side front calliper had sticking pistons. So I replaced both fronts with recon units and it now pulls left and locks the driver side first. Discs are almost new but tyres are close to the limit.

I have recon rears but they are a nightmare to fit so left them in the box for the time being.

This makes the car horrible unstable under hard braking especially if the roads are a bit bumpy.

I am going to bleed the brakes again and check it all over but what else could cause this.

TVM

Dale

[kayjayd]

Originally Posted by daleb

As far as I remember there were no shims to install as the joints were self contained and did nto have grease nipples.

Hi Dale,

You should have castor shims installed to the front of your top ball joints as per the attached pic. Ignore the fact the nuts aren't tightened up, this is an early pic of my build

[Purple AK]

Originally Posted by daleb

Hi

I have an 02 AK , jag XJS based, 5.7 chevy which stopped self centering when I renewed all the ball joints on the front. As far as I remember there were no shims to install as the joints were self contained and did nto have grease nipples. It does seem to be improving as I get more miles on it.

How do I measure castor. Ride heights are set up as per AK's instructions using spring preload and typical driver passenger.

And brakes. It was pulling left under braking and I found the Drivers side front calliper had sticking pistons. So I replaced both fronts with recon units and it now pulls left and locks the driver side first. Discs are almost new but tyres are close to the limit.

I have recon rears but they are a nightmare to fit so left them in the box for the time being.

This makes the car horrible unstable under hard braking especially if the roads are a bit bumpy.

I am going to bleed the brakes again and check it all over but what else could cause this.

TVM

Dale

Dale. There should definately be shims between the top arms and the top balljoint! Normally 3-4 at the front. Otherwise it wont self centre

[wilf]

Also check corner weights if sorting the geometry still leaves you with a brake pull.

[TINKA]

Check the steering arms and that the bolts holding them on are OK. One of my bolts holding the steering arm on snapped with out me havung any knowledge at all about it, only symptoms were pulling to the left when breaking, eventually ( over a year later ) fatigue set in, and the steering arm broke. Worth checking.

There should be shims on the top ball joint, but unlike what other people say there is no hard and fast rule to weather they go in front or behind. To measure the angle you need to get the car on angle stands so it is level, remove both brake calipers, you will then see two flats on the upright about 2" apart on either side ( sorry no pictures it was a long time since I did this ) these two flats are what you need to put the plumbod guage against, that AK recomend you make and use to set up the geomitry.If you dont know anything about the guage give Ken a ring at AK. From memory 5 deg is about what you need to aim for. HTH

[chesterak]

As Wilf has said...you cannot set up the suspension just by measurement of chassis and/or spring platform height you have to measuer corner weights and "balance" the car. I had exactly the same problem and discovered significant inbalance at the front, readjusting cured brake pull.

[lutman]

Good example of what was being mentioned in another thread about tyres. Suspension set up is critical for safe running of the car.