'63 steering gear box adjustment

[Richard P.]

Based on member comments to one of my previous threads and also an opinion of a local mechanic that my steering problem "probably" is caused by a misadjusted steering gear box I'm going to let him adjust it.

Is it true that there are only two adjustments; 1. Worm bearing and 2. Lash and that these can be done with the box on the car and the pitman arm must be removed during adjustment? Is it this simple or am I missing something?

Its a new box installed only 50 miles ago. It may or may not have been adjusted by the factory or the mechanic who did the installation. The steering problem is no recovery after making a turn and hard steering in general. Its a power steering car. Thanks in advance for your replies.

[Joe R.]

Re: '63 steering gear box adjustment

Richard,

Obtain a 1963 Corvette Shop Manual and refer to Standard Steering Section 9-2 under Maintenance And Adjustments.

JR

[Duke W.]

Re: '63 steering gear box adjustment

It's difficult to properly adjust the worm bearing preload and total preload on the car. You said the steering gear is "new", which I assume means that it is freshly rebuilt. In this case you should talk to the rebuilder and verify whether or not it was properly set up.

In addition to worm bearing and total preload there's also a sector shaft shim choice to allow proper sector shaft end play. Setting up the gear is fairly straight forward, but it requires attention to detail, patience, and a 50 or preferrably 25 lb-in dial torque wrench.

Your symptoms could also be insufficient caster, but if alignment has not changed and the steering felt okay before the gear was rebuilt, then the problem is most likely the steering gear.

As Joe said, study the '63 shop manual to understand how the job should be done and pay particular attention to the worm gear and total preload specs.

Duke

[Timothy B.]

Re: '63 steering gear box adjustment

Also, you stated the car has power steering but remember the corvette power steering is only power assist so it does not feel as easy as the later power steering where the assist is in the steering box.

[Richard P.]

Re: '63 steering gear box adjustment

Thanks to all who replied. One quick question regarding the caster comment. Just had a four wheel alignment with the following result for front caster:

Left Front: +1.7 degrees
Right Front: +1.7 degrees
Cross Caster: 0.0 degrees

These readings seem well within the specified range and I discounted caster as an issue based on these results. The alignment shop says they used a "Corvette 1963-1965 (Modified Specification). Should I revisit caster as a potential cause of my problem?

[Duke W.]

Re: '63 steering gear box adjustment

That's enough caster. For power steering 2+ is best, but some chassis can't get that much within the available range of adjustment, however, I doubt if the problem is lack of caster.

Duke

[Richard P.]

Re: '63 steering gear box adjustment

Thanks Duke, I'll pursue the gear box adjustment as the next step and keep my fingers crossed.

[Gary R.]

Re: '63 steering gear box adjustment

Based on member comments to one of my previous threads and also an opinion of a local mechanic that my steering problem "probably" is caused by a misadjusted steering gear box I'm going to let him adjust it.

Is it true that there are only two adjustments; 1. Worm bearing and 2. Lash and that these can be done with the box on the car and the pitman arm must be removed during adjustment? Is it this simple or am I missing something? Its a new box installed only 50 miles ago. It may or may not have been adjusted by the factory or the mechanic who did the installation. The steering problem is no recovery after making a turn and hard steering in general. Its a power steering car. Thanks in advance for your replies.

Hi Richard,........ First concern I have is you said this is a "new" box. There have been attempts at building new boxes since the Saginaw division stopped making them and sold off the machinery. The ones I have seen and repaired were very poor at best. If the box is the original rebuilt then you shouldn't have any issue with it at all, however that is not the case. There are the 2 adjustments you referred to but if you just want to see if the lash is out all I would do is get the box on center and see if there is play in it at that point. If so look at the cover and the jam nut. See if there are any threads showing above the jam nut, hopefully there will be 2+ showing. If the box is loose then loosen the jam nut and turn the screw CW until you feel resistance, a little is ok but you want to feel some. Stop there, DO NOT BACK OFF THE SCREW as I have read too many times on CF, that accomplishes nothing and tells me the people that recommend that don't know what they are talking about. Then take the car for a ride and see how it is. Again assuming the box was indeed correctly rebuilt or built this maybe all you need. If on the other hand you don't see any threads and the steering is loose I can guarantee you have bad gears in the box. Guys have sent me boxes from many of the vette rebuilders out there and everyone was bad. If you want some advice before digging into this just let me know. I go over this and other rebuilding at Carlisle every year in the seminars I hold, I will be glad to speak with you.

[Jim S.]

Re: '63 steering gear box adjustment

The Boss man has spoken. Listen to him.

One further comment. Worm bearing lash will show up as an axial movement of the input shaft (in and out of the gear) as you turn the steering wheel clockwise and counterclockwise. There should not be any noticeable axial movement if the worm bearing is adjusted properly. Any axial movement is lost motion and will result in you moving the steering wheel with no movement of the road wheels until the input shaft bottoms against the internal gear bearings. With older gears that have been in service, you may even detect a small polished area on the input shaft that will be an indication of it moving in and out. You must address worm bearing lash first before trying to adjust the sector shaft. Specs for the worm bearing adjustment are in the Chevrolet shop manual or have Gary do it.
Jim