Steeringbox

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Submissions by Jacks.

Steering:

See also [1]

Type:

Worm and re-circulating ball nut:



The working of the steering gear is the worm and recirculation ball and nut type in which the ball mounted on the worm is driven through steel balls which functions as a rolling thread, there are 50 balls, optional 54 balls for power steering. There should be around a 1/4 of a litre of oil in the steering box.

Faults:

Excessive Play or Looseness in Steering Gear:

This can be caused by the steering gear been worn out, if so you may need to renew the faulty components and adjust
Pitman Arm may be loose on the Sector Shaft, so may need to tighten the retaining nut.
Idle lever Bush and bolt may be worn, then renew and adjust.
Steering gear might be loose on the sub-frame mounting bolts, so re-tighten the mounting bolts and then check alignment of steering gear mounting.
Steering linkage Ball Joints maybe worn or loose so renew faulty components or tighten them up.

Steering box adjustments:

The lash adjustment is made integral with the Sector Shaft and the rack of the Worm Shaft, if the steering box is still attached to the vehicle, then you will need to remove the Pitman Arm, you might need a puller for that
The reason for removing the Pitman Arm is that we need to isolate the steering linkages etc away from the movement we are adjusting, so we don’t get a false reading, some might say leave the Pitman Arm on, but that’s not the correct way.

Adjusting the Lash Between the Ball Nut and Sector Shaft:

With a ring spanner. unlock the sector shaft adjusting screw lock-nut, then with a screwdriver turn the adjusting screw anticlockwise a couple of turns, we will come back to that later on.
First we need to adjust the Worm Shaft until we get the right pull of the pre-load which is obtained by a spring scale attached at right angle to the steering wheel spoke mounted 7�? from the centre of the wheel

Worm shaft location:

It’s located under the flexible coupling of the steering shaft, on top of the steering box assembly, there you can see a big nut adjusting nut this holds the worm shaft into the steering box assemble, and another thinner bigger nut that has notches cut into the rim /edge of the nut adjusting lock-nut it holds the adjusting nut into a locked position when the pre-load has been set.

Unlocking the Worm shaft:

In order to adjust the pre-load on the worm shaft, you will need to tap the thin lock nut by placing a suitable blunt chisel or dowel punch in one off the notches and using a hammer , hit the thin large nut anticlockwise then you will be able to move the other larger nut accordingly . Adjusting nut Clock wise to increase the pre-load, anti clockwise to lesson the pre-load.

Worm shaft pre-load:

The worm shaft has a pre-load setting on it, the setting is done with a spring scale that’s attached at right angle to one of the spokes on the steering wheel, you need a pre-load setting of 4-12 ozs, and the pull is at a 7" radius. I doubt if you have the gear to do it this way,with a spring scale, but if you do then there's the info, it’s not rocket science, so read on.

Pre-load explanation:

The pre-load, well its a bit like when you tighten up your front wheel bearing, you nib it up and then come back a bit, this is to allow for expansion of the bearing for when it gets hot, now if you didn’t, and just locked them up tight, the wheel would need more force to rotate it, and the bearings would soon heat up and fail, (too much tension) well this is similar in a way to the steering mechanisms, they call it pre-load, meaning the workings of the worm shaft is by rotating the steering wheel, this rotating force needs to be freely, yet firmly, with just a little tension 4-12ozs its called Pre-Load

So at given mark, 7 �? out from the centre of the steering wheel (radius), we can then pull at right angle to a pressure of between 4-12 ozs using the spring scale in order to rotate the steering wheel.
However, if more pressure is required to move the wheel than what’s recommended, then the pre-load on the worm shaft bearing in the box is too much, so you need to loosen off the adjusting nut, anti clockwise
If it moves with less than the recommended pre-load ,then the steering wheel is too sloppy, so you then need to increase the adjusting nut clockwise direction to put more pre-load on the worm shaft.
Note: when you're adjusting, you need to move the steering wheel from lock to lock, in order to get the worm shaft pre-load setting correctly.

No Spring Scale:

If no spring scale is available, you should be able to put your index finger on the spoke of your steering wheel 7" from the centre, and move the steering wheel from lock to lock with a force of 4-12 ozs, so not much pressure is required really, if you find something of that weight,4-12 ozs then move it with you index finger you will get an idea of the pressure required to move the steering wheel, pretty simple.

Now once that has been all set correctly and the adjusting lock nut is locked up, we then need to move onto the final adjusting, that’s the bit I said I’d come back to later.

Sector Shaft:

You will need to turn the steering wheel from lock to lock, then counting the number of turns, turn the wheel back to the central position. You now turn the sector shaft lash adjusting screw in a clockwise direction with your screw driver, until a pre-load tension has been obtained with the spring scale, rotating the steering wheel through the central position as you did earlier when doing the worm shaft pre-load setting.

Pre-load for sector shaft:

You know what pre-load is by now, only this time it’s the sector shaft pre-load, and there is a lot more pre-load required here, it’s 20-28 ozs and with a 7" radius, so yes we use the same mark as before on the steering wheel, you must also move the steering from lock to lock to correctly set the pre-load. If the steering gear assembly inside the box is badly worn, then you may need to replace some parts, as wear and tear usually takes place in the middle of the shaft, as that’s were most of the steering movement has been done, rather than at the end of the wheel locks, so you will notice it gets tighter at the end of the steering lock when adjusting the lash screw. If the movement is really sloppy in the middle, then you may have to remove and replace the worn parts
When the pre-load is set correctly then lock the adjusting nut up with the ring spanner, and refit the pitman arm .

Please feel free to add, or correct,
When time permits, as I shall add more info, as well as some pics.
Jacks.

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