Suspension Arm Question For a 1941 Cad

[Mike Wenrich #1666]

I have been changing the coil springs and while I had the suspension arms down I noticed I was having difficulty getting grease in the upper suspension arms.  I also noticed the spindle assembly was tight fitting and to make a long story shorter, I loosened the clamp screws and the grease fitting.  Using an allen wrench I could not turn the threaded pin unless I loosened the end caps.  The one cap is supposed to be torqued at 155 LBS and it looks like the other is captured in the assembly and would become tightened with the other one.  But when I snug everything the steering knuckle becomes tight when moved inwards or outwards.  I have not connected the lower suspension arm with the spring yet and I am concerned something is in a bind.

Anyone have an idea what is going on?  Is it supposed to be rigid when everything is tightened?  Since there are grease fittings I would think it is designed to move.  I was able to get grease in the fittings on both sides but the grease pushes back out on the rear side.  Probably a faulty fitting but it looks like a non removable fitting on that side.

[Steve Passmore]

I assume your talking about the top camber and caster concentric adjusting pin and its bushings? (that which your calling 'End caps')  These are screwed onto each end of the pin as you know but the suspension works buy moving on the threads so they must have room to move within the threads for the travel of the lever action shock arm.           If the pin is done up too far one way it will bottom in one bush before reaching the required travel of the shock.    When doing up the bushes the pin should start off by being in the centre of the shock arm eyelet.
You should not loosen the bushes anyway but loosen the clamp bolt in the shock arm. this allows the pin to rotate for adjustment.
You are not supposed to tighten the pin anyway with the Alan screw, that is for adjusting your Caster and Camber. Its supposed to be suspended between the bushings for movement. Screwed to the bottom of a bush and the grease cannot get in.
If it was bottoming in say the rear bush you should have unscrewed the pin a full 360 degrees to maintain your Camber but remember you have then altered your Caster.
If the car has never had trauma to the front everything should be about centre but who knows what past owners have done to these cars?

[Mike Wenrich #1666]

I was thinking about this very thing overnight when trying to sleep.  That I have the bushing bottomed against one side or the other.  If I am looking at the assembly correctly, you only torque the back side bushing since the other side is captured by the thru bolt.  I know the caster camber is all out of adjustment and I will need a pro to set it up.  Many years ago I changed king pins and had this assembly apart.  Memory fails me now, what I did at that time but the bottoms of the lower A arms were rusted out and I had plates welded over the base of the springs.  Now I found good replacements.  So changing all this out has taken everything out of adj. 

I was trying to roughly center the assembly between the shock arm opening.  I will go back after this today and see if I can improve the vertical travel resistance.  The explanation that the movement is on the threads helps me better understand the situation.  Thank you.

Mike

[Paul Phillips]

Mike
The torque on the rear bushing is the one that is important, the pinch bolt on the shock arm is used to lock the front bushing in the right place to time the threads and keep things snug. It is ok to use a shim on the front, if needed to have that snug up and be timed correct on the center pin.

Starting with the center pin in the middle of the shock arms should give you the right adjustment range for caster & camber. Process is to get caster about right, then camber is within +/- 1/2 turn from there. To set caster & camber, keep the pinch bolt tight on the shock arm and loosen the one on the spindle.

As to lubrication, there should be a zerk fitting at both ends of the upper pin, don't expect grease to flow thru from front to back,  there should be a rubber grease seal on the inboard side of each shock arm.

Hope this helps!
Paul

[Mike Wenrich #1666]

Yes it does Paul.  I was in the dark on the front fitting because no mention was made of it in the Cadillac manual.  I ran into another problem today while trying to change out the lower A arms.  When I mounted the A arm with the four bolts to the frame and lifted the arm up to attach the lower spindle bolt, the spindle did not fit in between the lower A arm ears.  I tried adjusting several times to get the correct adjustment and could not get it to work within tolerances.  Finally went back to the original A arm and it was okay.  I determined there was a slight bend in one of the ears on the replacement A arm.  Seemed minor but I had to go with the original, which had previously been welded on the bottom in the spring mounting area due to rust.  Disappointing but at least I will have new springs up front and hopefully a front end man can adjust the caster/camber without difficulty.  A blind man looking underneath won't notice the weld.  I don't think many others will either.

Mike

[Steve Passmore]

. To set caster & camber, keep the pinch bolt tight on the shock arm and loosen the one on the spindle.
Paul

Sorry for the typo, Paul is right there. The pinch bolt in the Support Arm for the pin adjustment not the shock arm.

Mike. I have had this before when things don't line up. Its sometimes caused by some trauma to the front like hitting a curb or something in its past life and everything gets just a tiny bit bent. The Support Arm only has to give a fraction at the top or the smallest bit of movement on the lever shock arm to multiply this on the bottom arm alignment.  Its possible also your rusty bottom arm was weak and allowed things to move slightly on the top over the years, now everything is set slightly differently.