Steering self centreing

[dave364634]

When I drive in a straight line my car goes to the left much easier than to the right.

Also after turning left it won't sell centre properly.

I take it this isn't normal, and after takeing several guesses at the o/s/f camber it's still wrong????

Ta.

 

[zcacogp]

Could be a bunch of things, but I'd start with the geo for sure. Camber or alignment.

Are both the tyres on the front the same brand and similarly worn?


Oli.

 

[Copperman05]

Due to camber of the road cars will pull to the left naturally, but its usually quite gentle, as Oli states you probably need a geo, but I would sort out any mis-matched tyres first, should be the same brand and type all round.


Edd

 

[944 man]

If this was a new card Id tell you that they all do this. Theyre set to counter the camber, but like the rear wiper and series one windscreen wipers: no one bothered to adapt this for our roads.

Porsche Cars GB would adjust this for you if you didnt like it.

 

[George Elliott]

Dave

The problem you have is unequal Castor IMO

As a rough guide, you can look at the tab on the Castor adjustment.

If you view from the front below the batwing, looking to the rear, there are two steel tabs about 19mm x 25mm long. They locate the rear of the lower wishbone. If the tabs are oriented around towards the centre of the car, the castor setting is minimal. (wishbone in and front lower ball-joint back) If they are rotated to the outside (away from each other) they will increase castor. I reckon you may have one at 5 o'clock and one at 7o'clock. (and remember 5 o'clock on the n/s is 7 o'clock on the os[8|])

Minimal castor is about 2Deg, Max is maybe 4.5Deg. The difference is massive. With a small castor setting the wheel talks to you, with loads of castor its heavier, more remote, but probably better over 130mph.

this assumes you don't have one tyre at 12psi and one at 45psi, and a binding brake caliper.

That 19mm number is where an open end spanner can be fitted to make adjustment (but the nuts need to be loosened on the end of the castor pin, which are 19mm AF and not to be confused with the castor block to body bolts which are 17mm AF)

If the castor is up the left, or the castor block rubber is shot, it will need to be replaced, but the camber & toe will then need to be realigned. Its possible to improve it 90% with some common sense or if you want absolute perfection, then Centre Gravity, Atherstone.

hope this helps
George
944t

 

[dave364634]

The batwing?

I'm going to MOT it tomorrow, and probably order 2 front dampers and get it aligned.

 

[George Elliott]

Dave, sorry - below the front spoiler lower edge
George
944t

 

[dave364634]

But I never altered the castor to do the bearing....


On the MOT there is;

1 - n/s/f brake low efficiency
2 - n/s/f wheel bearing play
3 - play in both front damper rods
4 - play in both inner rack joints

 

[JamesO]

Were they fail points or advisories? I had an advisory on one inner tie rod once and in my opinion it should have failed as the steering felt awful. point 4 sounds like the culprit if you haven't fixed it. In my experience with these cars, they can pass an MOT but feel like crap to drive.

 

[dave364634]

All advisorys.

Can you get new rack ends or is it a replacement/used rack?

 

[ChasR]

On my old S2 the PO changed the track rods via replacements on ECP going through the previous receipts. Going onto their website now though, it seems the price has almost doubled in 5 years on them though (although they are Lemforder replacements). Berlyn now seem to be the cheapest by a small margin.

 

[JamesO]

Bert at Berlyn services supplied me two inner tie rods for a reasonable price, IIRC they came with the track rod ends included, making it not a bad deal at all. Pretty easy to fit but will need an alignment afterwards.( Assuming the tie rods are causing the play and not the rack itself).

Not sure if a refurbed steering rack comes with tie rods?

ETA

Just re-read the original post, replace anything with play in it, tie rods etc then get an alignment done. No point in aligning something that's worn out or you'll pay to have it done twice and guessing wont work that well.

 

[George Elliott]

But I never altered the castor to do the bearing....

Fair enough Dave, but I mention Castor as it has a dramatic effect on the Steering self centre loads.

Track rod / rack cannot give unequal steering load, its either worn and loose or its not.

Camber cannot give unequal steering load either, its just the incline of the wheel to the road.

One thing that could be a problem though is the UJ (or double UJ actually) in the steering column as it connects to the rack. If the (usually lower) joint which goes around quite an acute bend is worn the loads will feel bad, but that will likely apply both ways not just to one side.

Hey, I'm just suggesting from my limited experience and a great distance.

good luck

George
944t

 

[JamesO]

ORIGINAL: George Elliott

But I never altered the castor to do the bearing....

Fair enough Dave, but I mention Castor as it has a dramatic effect on the Steering self centre loads.

Track rod / rack cannot give unequal steering load, its either worn and loose or its not.

Camber cannot give unequal steering load either, its just the incline of the wheel to the road.

One thing that could be a problem though is the UJ (or double UJ actually) in the steering column as it connects to the rack. If the (usually lower) joint which goes around quite an acute bend is worn the loads will feel bad, but that will likely apply both ways not just to one side.

Hey, I'm just suggesting from my limited experience and a great distance.

good luck

George
944t

Fair comment, I may have replied to the topic when less than sober.. But I do stand by replacing the worn bits before going further.