Polybronze bushings (long)

84toy · 10:42 PM

I have just installed Chucks Polybronze bushings and thought I would post a couple of tidbits that I did. On the front I sandblasted and coated the inside of the front and back bearing holders with Devcon metal putty and then chucked them up in my lathe and machined them to the exact interferance fit and pressed the bushings in. The front bearing holders are a two piece unit welded together and have a large gap at the joint of the two pieces. These were all filled in and machined perfectly round. I used no shims since I could machine to the exact tolerance needed.

On the rears, I coated the inside with a light coat of Devcon metal putty so I would not need shims. When this product is not machined, it is like gritty sandpaper when hardened and is perfect for holding a grip on the poly portion of the bushing. This worked perfect, the bushings pressed in firm and straight. I don't klnow why but I don't like shims but they should work. Another thing I did was I assembled the side plate with the bushings installed and held it firmly together by hand and measured the gap between the side cover and the body. I then used washers to get an exact fit. This will prevent side to side movement. Chuck provides washers that are the exact thickness to make up for the added thickness of the bushings but I wanted to fit mine exactly to my car. The left side was really different and I only used very thin washers behind the cover plate to get no movement side to side instead of the provided thick washers. Anyone can do this if they have a handful of different thickness washers and a little patience. The front and rear both move easily but firm enough to stay still on their own weight. One helpful thing is as you snug up all the bolts, rap and shock around the bearing areas with a large brass hammer, you would be surprised how much smoother you can get everything to work by "settling in the parts". In addition, when I installed the front and rear inner races to the shafts, I sandblasted the surfaces and used the Devcon to bond the races to the shafts so no shims were required and the races stay perfectly round.

In closing, I think the Polybronze bushings are an excellent product and will work as supplied. Chuck is a first rate guy to deal with. What I did is probably a little on the anal side but I am always that way on machined parts. Too many years as a machinist I guess. I can't wait to get the car out for a test ride but I am waiting for the return of my shocks from Bilstein......

makaio · 12-13-2003, 11:55 PM

Quote:

Originally posted by 84toy

Chuck is a first rate guy to deal with.

Yes he is.

speeder · 12-14-2003, 12:46 AM

Paul, Wow, sounds really great even if I'm not familiar w/ all of the fits that you are talking about. Did you take pictures by any chance? Good write-up anyways, Now I want you to help me w/ mine. Bribe time, I guess.

And Chuck is one of my favorite people. Back before Elephant, he was THE greatest DIY guy on this board, IMO. ANd always w/ a mini tech article in the post.

911nut · 911nut's Garage

Denis, I second your opinion of Chuck. Great guy to work with and talk to.
Paul, yes, I too ended up using thinner washers on the left than the right. In fact, I couldn't use the Elephant-supplied spacers.
Shimming the aluminum races was the most difficult and time-comsuming part of the job. However, when all was done I was and still am very happy with the results.

84toy · 12-14-2003, 08:54 AM

Here is the gap we are talking about. I would custom fit with washers...
The one thing that you can do to avoid the shimming of the races is to use the Devcon. I originally thought of JB weld and talked to Chuck if he had ever tried it but he was concerned about the races not centering properly since the epoxy could oose out of one side and cock the race which was a valid point. That's why I used the Devcon metal epoxy, it's just as good and contains gritty metal particles that center the race. When you coat the inside of the race and the outside of the shaft and assemble it, you have to rotate it together with a some effort and they do not move at all after assembly even before the epoxy sets. One warning, you will have a more difficult time removing the races some day if you want to replace them. I suspect it will take heat and/or a chisel to get them off but still easier than the originals I suspect.

scca_ita · 12-14-2003, 08:55 AM

hummm, while this sounds like an endorsement, these bushings are starting to make me feel that the average guy is not equiped to do the proper install without spending more money.

I am going to look at a set today, but figured this product was a slip on and go.....

makaio · 12-14-2003, 09:01 AM

They are a product for the average DIY'er. Paul just took some extra steps, that he felt would help him make his suspension perfect.

scca_ita · 12-14-2003, 09:08 AM

Where exactly do the shims go for the front bushing install? Pics? Thanks

84toy · 09:30 AM

As for the endorsement, I have never talked to Chuck and didn't even know who he was until I called Elephant to discuss the bushings. The kit will install just the way it is provided and it is clear that extra effort was made for the DIYer. I only posted the extra info for those that have more shop equipment.

scca-ita.....enough shims are provided to custom fit each bushing to it's location. The shims are wrapped around the bushings until a light interference fit can be achieved. The shims make up for variances in production.

Chuck Moreland · 12-14-2003, 09:53 AM

Paul, Glad to hear this worked out.

To clarify for anyone not familar with the product, Paul's installation technique is not the normal method. He is a capable machinist and wanted to experiment a bit. We discussed his approach and agreed it should work.

The procedure for installation explained in the product instructions is very different and does not require the extra machining steps and Devcon putty that Paul used.

jyl · jyl's Garage

Don't get the wrong impression. It's really no big deal to install the polybronze bushings.

The fronts took me maybe 20 minutes for the actual installation including figuring out which shims to use - excluding of course removing and repainting the A-arms.

The rears took longer, maybe 1 hour, because the inner races were a tight enough fit to require extra wirebrushing / sanding of the torsion bar tube part of the spring plate. Again, this excludes disassembling the rear suspension enough to remove the spring plate.

Bottom line: I am a DIY dummy with only hand tools, and I managed it w/ no problem.