Steering

[Inigo]

My Fulvia is an S3 1976 - 818.630 0798 01 and need advise about the steering which is precise and with no vibrations, but when I lift my foot of the accelerator the steering feels dead for a second and I get the feeling that the car moves from left to right/right to left. Any advise would be much appreciated.

[Huib]

This is play in one of the steering components. In order of likelihood:
steering ball joints (track rod ends)
steering idler box
silent blocs of lower wishbone
suspension ball joints

The last few months I have seen many bad idler boxes. Sort of epidemic.

If you apply throttle, the front wheels pull the car and the wheels try to pull themselves inwards (toe in).
If you lift throttle the car pushes the front wheels and they try to go outward (toe out).

If you have play on one side (respective to the steering box), the wheel goes outward on that side when you lift the throttle and the car goes to that direction. Vice versa when you apply throttle.

[lancialulu]

Idler box is major suspect as the later ones had plastic instead of bronze bearings. And the plastic wears as Huib says like an epidemic. easy to remove and have two new bearings inserted. My shop found some camshaft bearings from a Jap truck wear the right size.....

[lancia7550]

I read this with interest as I have some play in my steering after replacing all parts mentioned with new ones, except for the steering box and idler box.

I have new bronze bearings for the idler box but did not bother replacing it while all parts were out because I could not detect any lateral movement on the shaft while holding the box by hand.

Is there a certain way to diagnose if the idler box has worn bushes, either inside or removed from the car?

Any chance of the play being caused by the main steering box? The car has rather low mileage but the box was dry when I started restoring it. I have adjusted the play on both boxes in the prescribed way but it did not make much difference.

Thanks
Albert

[Huib]

Albert,

I understand from your posting about the S1 servo, that you have an S1 car.

S1 Fulvia's (and early S2's) have an idler box with grease nipple. These have bronze bushes inside which hardly ever wear.

On the S2 / 3 Fulvia's another possible source of play are the cardanic joints on the collapsable part of the steering shaft. See my posting http://www.viva-lancia.com/lancia_fora/ ... sg-1188294

On the S1 cars, there is a so called Hardy disc between the steering box and the steering shaft. It is a disc made of 5 layers of canvas with thin steel segments on both sides of the center layer. These are 90 degree segments of thin spring steel. Segments 1 and 3 are on one side of the center layer. Segments 2 and 4 are on the other side. These usually have rusted away. If the canvas layers start to come apart, this is the sign that the steel has gone. The canvas itself is not strong enough to handle the forces by it itself.

I have bought some replacement discs which are available from Lancia part suppliers. These look fantastic but the steel sections are missing. Apparently someone reproduced the part without noticing the steel sections inside or he used one as an example where the steel had already completely disappeared (not uncommon). These imitation discs are extremely dangerous. They tear in half within 6 months.

I have a stock of thin spring steel (stainless) and can water cut the sections. I have never been able to find canvas of 1,5 mm thick. If someone can help me find canvas of 1,5 mm thick I can reproduce the part properly.

Alternatively you can go to the Mercedes Benz dealer. There was a Mercedes in the sixties which had a Hardy disc with the same dimensions. It is made of solid rubber with steel bushes where the bolts go. It can perhaps also tear after many years. That Mercedes has a fail safe construction around the disc.
The Fulvia does not have that fail safe construction. I would therefore prefer to have discs like the original with the steel sections to handle the forces and the canvas doing the fail safe function.

So, please, if anybody knows where I can source the canvas, let me know.

And if anybody know how to fix the cardanic joints on the S2, let me know too.

[lancia7550]

Yes, my car is late (1970) s1 but does have a grease nipple on the idler. I guess there are no.guarantees though that it has ever been lubricated.

I have bought a hardy disc from omicron if I remember correctly but I will have to.check if it has steel between the layers.

Would it perhaps be possible to make a disc entirely out of steel or aluminium? The S2 is fine without the damping from the disk.

[Huib]

It is not really the damping of the disc that is important. It is the flexing. It is impossible to guarantee that the steering box and the steering shaft are exactly in line. The subframe is mounted with rubbers. The steel of the body and subframe flexes. Whenever you apply forces to the car such as accelerating, decelerating, cornering, loading the relative positions of and angle between steering box and steering shaft changes.

[lancia7550]

Hi,

I manged to order a mercedes rubber steering disc. Hopefully it is the correct one. As soon as I get it and it is correct I will post the part number on here for future reference.

My current steering disc is made out of canvas and does not appear to have steel reinforcement. It is still in as new condition but I can see how it can introduce vagueness in the steering if it is not stiff enough.

Huib, just referring back to my previous post- it would be really useful to know how to best pin point steering box or idler box play when inspecting the steering components (ignoring the obvious signs like pulling to one side when accelerating/ backing off).

Thanks,
Albert

[Huib]

I have never found any instructions in the books.

What I do is:

idler box:
screw down the adjustment screw till it is fully locking the shaft. Back off till you can swing the Pitman arm without resistance

steering box:
Make absolutely sure it is in center position.
Screw down adjustment screw fully till it can't go further
Back of adjustment screw 1 turn on new steering boxes, 3/4 of a turn on used but good steering boxes.
Test result by turning steering wheel. Usually there is slight resistance when passing the center position.
If necessary play with the position of the adjustment screw.
Do never tighten the adjusment screw with the steering box not in center position. If you turn the steering wheel the housing may crack.

If you have the steering box on the bench, check surfaces of worm and roller. You may assemble with the roller in a different position.
Needle bearings for the vertical shaft???
Axial play of the roller.
Axial and radial play of the bearings on the worm shaft. You can adjust by changing the shims under the rear cover.