• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
  • When posting a classified ad, you MUST select a prefix from the drop-down next to the subject line. If you don't you will get an error and your ad will not be posted!
Tips
Tips

TR2/3/3A TR3, Front Suspension

Share this page

I

IKE

Freshman Member
Country flag
Offline
I'm rebuilding my 1960 TR3, working on replacing all the bushings using a kit from Moss. The clearances between the bushings, specifically the wishbone pivots seem to be very sloppy. Is that normal? Advice? I'm considering making my own bushings.

If this has been answered, perhaps a direction would help.

Thanks

Ike
 
Which ones?

The lower outer bushings are supposed to be reamed to size after installation in the arm, which should result in a clearance of only a few .001" to the pin.

The nylon inner lower bushings are somewhat sloppier, but not hugely so unless the arms are worn/damaged. The steel sleeves inside the nylon should be replaced, so just a light slip fit inside the bushing.

The upper inner bushings are supposed to be rubber that fits quite snugly (deforms just a bit as the nut is tightened).

The triangle formed when the arms are joined to the vertical link is what locates it; one of the advantages of this design is that the individual pivots don't have to be precision fits.
 
Randall
The main concern is the steel sleeves/bushing on the inner lower fulcrum pins. - the replacment sleeves fit onto the lower fulcrum pins with too much clearance in my opinion so I'm considering making a new one that will just slip on and then add a drop of medium strength loctite to prevent rotation. I can also size the OD to provide a better fit with the nylon liner. Does that seem reasonable?

The upper fulcrum pins and new urethane bushings filt well and the assembly is tight. I will ream/hone the lower outer bushing for the proper clearance on the trunnion pins. I measure the trunnion pins at 0.620 - 0.621 and the recommended 0.625 reamed hole for the outer bushing is to sloppy - hence the idea to ream it to fit. All of the fulcrum pins and trunnion pins seem to be in good shape with little sign of wear or corrossion.
I figure the front suspension is one of the most critical assemblies so I want to get it right. Fortunately I have good shop in my garage so I can make the parts if necessary.

Thanks

Ike
 
This is getting confusing, with (at least) 3 different threads going on.

Making new steel sleeves would be OK, I guess, but I'm not sure the originals are ordinary mild steel. I'd be more inclined to order new ones from TRF and work on something else in the time I would have wasted trying to machine them.

Your outer pins do seem to be a few .001" smaller than the new ones I measured
https://www.britishcarforum.com/bcforum/u...buil#Post621144
but I don't believe it will make a noticeable difference in operation. Most cars use rubber in all the inner pivots, so the vertical link can move around by quite a bit under maximum cornering. In fact, the early TRs did as well, until they found that the rubber did not hold up well under the loads seen by the lower inner pivots. But since both sides move pretty much the same direction, the overall effect on steering is trivial.
 
TR3driver said:
Making new steel sleeves would be OK, I guess, but I'm not sure the originals are ordinary mild steel. I'd be more inclined to order new ones from TRF and work on something else in the time I would have wasted trying to machine them.
Click to expand...

In 1981, I got some lower inner fulcrum bushings from TRF that had the opposite ptoblem; the inner diameter was too small to fit over the pins. I thought that maybe they were supposed to be reamed to fit as the lower outer bushings are. There were no internet fora on which to ask questions like this back then.

I took the bushings to the same machine shop that did the outers. The machinist said that he ruined two reamers trying to ream them. Turns out the bushings were made incorrectly and TRF sent me new correct ones.
 
Randall - I took your advice and ordered parts from TRF. Sorry for all the confusion.

Ike
 
Randall - I pulled the following information together for reference and my own interest on the fulcrum bushings per recent discussions. Perhaps it will be of interest.

Old Bushings - perhaps from original 1960 TR3 - Material - 12L14 Steel with a surface hardness of 60 on the Rockwell C scale. A low leaded steel for easy machining then carburized for hardness.

New Bushings - Source - Moss or VB, not sure. Material - garden variety mild steel with a surface hardness of 60 on the Rockwell C scale. Probably carburized for hardness.

The tests were done in a lab using a fast, hand held x-ray fluorescence device (Niton XRF analyzer) where I used to work.

I think the parts were probably turned, heat treated then ground to size based on the surface finish.
 
Does that come Turbo Charged?

credits to "My Cousin Vinnie"
 
Back
Top