Swivel Pin Shims

[parrie]

Good Day All,

Just finished up installing new swivel balls complete w/ new railkos & bearings on my '61 109. Getting ready to install the housings but not 100% sure on the swivel pin shims. When I took the old apart the bottom swivel pin (steering arm) had shims...is this correct or does only the top pin get shims?

[cnfowler]

My old Haynes manual shows with the steering arm on the bottom of the swivel pin housing, only the top pin should have shims. Someone with more experience will chime in hopefully.


Colin

[parrie]

Thanks Colin. Thought it was odd there would be shims on the bottom...Makes sense to me that the bottom wouldn't get shims as this would effect how the pin seats on the bottom bearing. I haven't been able to find anything specific in the green bible, maybe I missed something, going to take another look.

[SafeAirOne]

Just have a look at the Parts Catalogue:

[lumpydog]

parrie - as you point out, the main effect of shimming the bottom is that it lowers the pin (and the bearing) in the housing, causing the entire swivel pin housing to sit slightly higher. Neither of mine had lower shims when I overhauled them.

[parrie]

Thanks for posting the diagram Mark...a parts catalogue I do not have. Although the diagram sheds light on the situation neither Colin nor Lumpydog has any shims on their lower pins w/o issue. On the one hand it makes sense that the bottom would not get shims thereby setting the bottom bearing however there is a case for shimming both top & bottom to more or less center the housing on the swivel ball. My guess is that you have done at least a few swivel ball rebuilds over the years...what has been your experience?

[I Leak Oil]

These aren't exactly precision machined hence some need shims on the bottom to preload the bearing correctly.

[parrie]

Thanks for joining the conversation Jason. How does one know if the bottom bearing is correctly preloaded?

[lumpydog]

Thanks for joining the conversation Jason. How does one know if the bottom bearing is correctly preloaded?

parrie - the workshop manual outlines the process of setting the pre-load for the swivel pin housing. The bottom bearing and overall preload are set using shims and torquing the pin's fixing bolts to the right setting. Trial and error, removing shims to increase load and adding shims to decrease the load. Follow the manual's direction and you will be fine. A few tips:
- using a simple fish scale does the trick for measurement.
- set preload with the swivel ball seal off.
- the series 2/2a workshop manual specifies a different pre-load (12-14lbs) than the Series 3 workshop manual (8-10lbs). Mine is a 2a and I set it to 14lbs of pre-load.

[parrie]

parrie - the workshop manual outlines the process of setting the pre-load for the swivel pin housing. The bottom bearing and overall preload are set using shims and torquing the pin's fixing bolts to the right setting. Trial and error, removing shims to increase load and adding shims to decrease the load. Follow the manual's direction and you will be fine. A few tips:
- using a simple fish scale does the trick for measurement.
- set preload with the swivel ball seal off.
- the series 2/2a workshop manual specifies a different pre-load (12-14lbs) than the Series 3 workshop manual (8-10lbs). Mine is a 2a and I set it to 14lbs of pre-load.

Thanks, this is making much more sense. I've looked at several different threads on the subject but none mention the bottom shims and the green bible isn't really clear. When I pulled mine apart and saw the shims were also on the bottom I had to understand why. So I presume, in theory, one should be shooting for relatively the same amount of shim top and bottom until the 12-14lb range is met. I will start w/ the shims listed on Mark's diagram and adjust from there.

Thanks guys

[lumpydog]

parrie. The shims listed in Mark's picture are a range of sizes (thicknesses) that can be used to achieve the right pre-load. Typically you would have 2-3 of each size on hand to test the amount/combo that works - using different thickness combos to bump up, or down the pre-load as needed. You can order a range of shim sizes from our sponsor.

You do not need to balance out every shim on top with one on the bottom. If it were my truck, I would return the shims that you found on the bottom, to their original location. Then add/remove shims from the top as needed.

[lumpydog]

I'll add these thoughts as you mentioned you swapped in new swivel balls and bushes, etc so the shim situation will likely be different. As mentioned, shimming the bottom moves the entire housing higher. This has several effects:

1) It means the axle's exit will be effected. This may have been why the prior owner (or factory) added them, to center the axle's exit through the stub axle. Test this before putting the swivel seal on, etc - , if the axle is angling up, and contacting the stub axle exit at the top, the swivel housing is too high - remove some lower pin shims. If the opposite is true, adjust accordingly.

2) It reduces the number of shims needed on the top pin. If you're finding you need a lot of shims up top, bottom shims can counteract the need. Again, check the axle's exit from the stub axle - it should not be contacting the exit and should spin freely.

[parrie]

I'll add these thoughts as you mentioned you swapped in new swivel balls and bushes, etc so the shim situation will likely be different. As mentioned, shimming the bottom moves the entire housing higher. This has several effects:

1) It means the axle's exit will be effected. This may have been why the prior owner (or factory) added them, to center the axle's exit through the stub axle. Test this before putting the swivel seal on, etc - , if the axle is angling up, and contacting the stub axle exit at the top, the swivel housing is too high - remove some lower pin shims. If the opposite is true, adjust accordingly.

2) It reduces the number of shims needed on the top pin. If you're finding you need a lot of shims up top, bottom shims can counteract the need. Again, check the axle's exit from the stub axle - it should not be contacting the exit and should spin freely.

Thanks again for all the great info...all makes perfect sense to me now. I have a pretty good stock pile of assorted shims so I should be good to go. Going to give it a go tonight, will report back.

[parrie]

I'm happy to say that my first attempt at installing the housing went surprisingly well. I started w/ .045" on top and bottom which was a bit stiff...added .002" to the top which put me at 14lb pull. Total amount of shims top & bottom is very close to Mark's parts diagram. At first look the axle exit looks good but I ran out of time, will confirm before locking everything down. Thanks again for all the great info!

[SafeAirOne]

Total amount of shims top & bottom is very close to Mark's parts diagram.

That's funny--The diagram isn't directive of the total thickness of the shims to be used, but rather an illustration of the variety of shims available. Quite a coincidence in your case.