Front Castor Problem

[cer444]

HI all

I have spoken to a couple of older mechanics about my castor problem and they had come across this problem of running out of adjustment.

They could recall a kit to pack up the rear of the cross member as I have done but very rarely did they come across it.

As for the spacer shims/tubes all they do is place pre- load on the rubber insulators to pull the crossmember into the chassis if it is too loose the front end will try to wonder all over the place, Too tight and when you hit a pot hole you will certainly feel it.

From my little experiance last saturday at the wheel aligner's you can take those tubes/shims out, tighten the bolts all day and for as long as your arse points to the ground IT DOES NOT ALTER THE CASTOR OF THE FRONT END!!!
.......well on my car anyway,

That spacer tool I,m stuffed if I know how that works!!!
because as I said before I cant move my top wishbones forward or back because then the nut bottoms out on the shaft before it locks on the wishbone!!!!

Any way The car is going back to the aligners on friday so I'll let you guys know how it goes with the dirty great big 3/8 shims I placed under there.

               Aaron

PS.... have a HR disc brake front end in the shed it's looking bloody good!!!

[craiga]

Aaron,

This is a very interesting and worthwhile topic - keep posting mate, it really does make interesting reading.

Cheers,

Craig.

[cer444]

I have opened a very big can of worms with a simple wheel alignment!!!!!!!

[Ed]

HI all

I have spoken to a couple of older mechanics about my castor problem and they had come across this problem of running out of adjustment.

They could recall a kit to pack up the rear of the cross member as I have done but very rarely did they come across it.

As for the spacer shims/tubes all they do is place pre- load on the rubber insulators to pull the crossmember into the chassis if it is too loose the front end will try to wonder all over the place, Too tight and when you hit a pot hole you will certainly feel it.

From my little experiance last saturday at the wheel aligner's you can take those tubes/shims out, tighten the bolts all day and for as long as your arse points to the ground IT DOES NOT ALTER THE CASTOR OF THE FRONT END!!!
.......well on my car anyway,

That spacer tool I,m stuffed if I know how that works!!!
because as I said before I cant move my top wishbones forward or back because then the nut bottoms out on the shaft before it locks on the wishbone!!!!

Any way The car is going back to the aligners on friday so I'll let you guys know how it goes with the dirty great big 3/8 shims I placed under there.

               Aaron

PS.... have a HR disc brake front end in the shed it's looking bloody good!!!

Hi Aaron,
interesting topic,
also the HR front wont necessarily solve your castor probs.  
my CRS V8 front may be way out, I dont actually know, can only assume its welded in a jig and OK.
Im going to drop my front end out nad have a good look now, the shims seem to make the most sense after looking again at the diagrams.

it's a worry to know that some cars bolt up perfect and others are somehow.. out of shape?

Cheers

Ed

[zulu]

This may or may not be part of the problem, but check that the steering knuckle and king pin assemblies have been installed on the correct sides. I once installed a left assembly to the right side and it played havoc until detected.
Gary

[Ed]

Looking on the american autos site,
they have 2 sets of insulator rubbers, 1 for FE with std front end.
1 for FE with HR front.

I reckon Ive used the std rubbers with the HR front end causing my probs.

despite the spacers only allowing different amounts of preload on the rubbers as Aaron suggests, the rubbers on the photos inf act appear to be much thicker than the stock items.

Aaron,
perhaps u can use one of these in the rear of your front end?

I will go down there on saturday to have a look and measure them up, if u like I will send thru pics of the height differences for you.

Cheers

Ed

[cer444]

Hi all

ZULU I did not know there is a right and left hand side for the steering knuckle? .......This could be interesting!!!

How do you tell a left hand from a right hand and visa versa

I reckon this may knock the nail on the head???

ED just hang off until I get a reply from ZULU
(and ED thanks very much for your offer)

[zulu]

The actual steering knuckle support assembly, (the long vertical piece that houses the centre of the kingpin) on FE & presumably all, these have left & right part numbers, don't recall if the numbers are forged onto the part though.
They look the same but I think the geometry is different.
Gary

[cer444]

Hi Zulu

In my spare parts catalogue the part numbers are as follows-

LH - 7408871
RH - 7408872

But the number on my knuckles are as follows-

LH - 7408871/2
RH - 7408871/2

So you would seem to think the knuckles are interchangable???

Maybe it is still worth swapping sides?

    Thanks Aaron

[cer444]

Hi all

Just have to place the correct "Terms" on a few thing

I was wrongly calling the "support assembly" a "steering knuckle" so-

Where your front wheel hangs off (the thing with the wheel bearings on it) is in fact a called a"steering knuckle"

The thing that joins you top & bottom wishbones is called a "support assembly"

So the part # for my support assembly is 7408871/2

I think I have confused myself and you guys enough for tonight!!!

I can't read the part numbers on my steering knuckles so I'm flying blind once again here!

       Thanks Aaron

[gp]

Hi guys,
I've been watching this thread with great interest......I haven't been able to contribute anything until now. The steering knuckle supports are DEFINITELY different for LH & RH. The hole/s where the king pins go through are at an angle, which affects the castor. So maybe you do have th LH one on the wrong side & vice versa?

Cheers,

Graham

[sgo]

Any up-dates?

cer444, how did the wheel alignment go?

Ed, did you learn anything about the different types of mounting rubbers?

[Ed]

Hi Sgo,

I learnt the lower HR x-member to FE-FC mounting rubbers are about 3/4inch thick (im guessing here as I have them in the shed at the moment and not here). (part # FEK4a rare spares).

The standard ones are maybe 1/4inch. (part # fek4 rare spares)
I used the normal FE/FC mounting rubbers and they are way too thin.

My next job will be to replace the 4 lower rubber insulators (all of same thickness funny enough) and squish them up to align the xmember.  Ideally I should use some sort of spacer shim as well.  This will be made out of an old spacer tube cut down to the correct height (to be determined).

Sounds easy but I have my motor in place LOL.

hope this helps

Cheers

Ed

[cer444]

Hi all

Had my ute at the wheel aligners today (suppose to be last friday but I was crook).

Anyway with my dirty great big 3/8 shims at the back the outrigger in the correct position ( not squeezing the rubber out the sides!!!) It had a big fat zero deg castor which is a lot better than -2 deg castor!!

Only 2 deg better than before,+ castor would be a lot better but the difference was like driving a new car!!
you would not think that just 2 deg would change the steering so much the car returns out of corners better, it stays on the road better and pretty much where you point the steering wheel the car now goes!!!

So with the shims still in place, sitting on 0 deg castor and still no castor adjustment I think it is time to swap the support assemblies over and see what that does.

just as well I know the wheel aligner personally as I think I have worn his machine out!!!


Also tried my newly fitted nasco warmride heater on the way in this morning "bloody beautiful"
             
             Aaron

[sgo]

Aaron, good to see it's working out.
What did you use for the spacers?

Ed, my set up used a stock/thin rubber on the front bolt and a thick/rare spares one on the rear bolt, but as it's all apart at the moment I can't really say how it all sat?

[cer444]

Hi all

sgo- I stole my Noltec crossmember bushes out of my drag car (LC Torana), Ground down the outer diameter and enlarged the centres slightly to fit the inne tube.

This is just a temporary fix as I have a gap between the chassis rail and the lower half of the insulating rubber.

I need to make a spacer that sits on the crossmember for the insulating rubber to then sit on to get full contact on the chassis.

I will post some pics to give you guys a better idea.

              Aaron