2 Tooth Steering

 

4/2010

Here are the details on the steering sectors. While all I have are 2 tooth units, the dimensions apply to the 7 tooth.

The bushings you buy from the supply houses appear to be a AA king pin bushing and are too big. They appear to have a nice fit after installation, but that is only a few high spots. If you hone them round they come out round at 1.127", we hone some round just to see.
The sector shaft diameter is 1.1235 on a NOS shaft.
The Ford print for the sector bushing calls out for the rough ID to be 1.122" to 1.124". Burnished ready to use the ID should be 1.12475" to 1.12575".
The original bushings were steel shelled with a copper lead tin zinc bearing surface.
The bushings listed in published bushing and bearing lists by some people are incorrect sizes, check all bushings before you buy!

Les Andrews on page 1-298 of his shop manual will give you wrong information. He lists the sector shaft with a 1.125" diameter and tells you to replace at 1.123". In effect, you will be throwing away NOS sectors in your search for the 1.125" shaft.

Needle bearings were all the rage at one point in time. They are no really recommended. The sector shaft is not really very hard. The very hard needle bearings are also very small so they have a small contact patch. Over time the needles may leave little dents in the sector shaft. While some have had long life with the needle bearings, most have found they caused problems.

To properly fix the sector shaft you have two options.

You can use the Clevite 0978 bushing that is sold by some of the A suppliers. If your teeth are good on the sector and you just have some wear then have the shaft built up. Put the bushings in the housing and have them honed round. Have the sector shaft hard chromed plated and ground to proper fit of your installed bushings.
One quote for this process is about $200.

If your sector shaft is not too worn then you can have a few thousands ground off the shaft to make it round. There are bushings available that have the correct OD and 1.0625 ID. You just need to install and ream close to size and then final hone to size. The bushings will cost about $10 ea.

Please note that I specify honeing to fit.
Never ream king pin or sector bushings to size.
You are just wasting your time and resources. Reaming leaves a surface with high spots. You have a wavy surface and get a tight fit on the high spots. These high spots will quickly wear leaveing a larger, looser hole. Most automotive machine shops have a Sunnen hone and should be able do the job. This will give you a tight bushing that will stay tight for a very long time.

Kevin Fehr