Elephant Bushing Tip-Suspension project update-Torque question
 

Since I've been recovering the last couple of days after getting my trailing arm pivot bolts out(!), I got back into it a bit tonight. The outer busing races on the Elephant units use a .012" shim as a base, which is pretty stiff. Instructions recommend tape to temporarily hug the tube prior to installing the race. I was struggling with tape that would hold, so I used zip ties, they worked great, making this a breeze:

http://forums.pelicanparts.com/uploa...1132705232.jpg
http://forums.pelicanparts.com/uploa...1132705264.jpg

Here are the new monoballs which almost didn't get installed due to my frustration on the pivot bolts. The old two piece parts came out easily with a bit of heat applied to the arm. The new parts, which I kept in the freezer overnight slid right in:

http://forums.pelicanparts.com/uploa...1132705353.jpg

Here's my sorry-a$$ed "plating" job on the covers:

http://forums.pelicanparts.com/uploa...1132705543.jpg

Ya' think I needed new bushings?:

http://forums.pelicanparts.com/uploa...1132705618.jpg
http://forums.pelicanparts.com/uploa...1132705662.jpg

Lastly, what is the torque for the trailing arm pivot bolts? I can't find it in my factory shop manuals or in Bentley.......I'm guessing it is "up there"?

What did you use for plating? I was thinking of trying it on my sprngplates

I used a loctite bearing retainer product to take up the extra space between the spacers and the race. It made installation a breeze. The bearing retainer product that I selected was good for up to 0.015" if I remember correctly. I used a pair of calipers to measure the gap down to 0.005 and then spread the retainer compound to lock everything down. Seems to have worked great! Your zip tie approach is definitely a process improvement. I used electrical tape, but this seems cleaner and easier to work with.

Are those the Weltmeister spring plates?

Doug

Those are Weltmeister plates.

I used a rattle can "cad" spray on. It's a little brighter than the spring plates, but it'll get dirty and cruddy soon enough.

Ed,
Looks great! Nice job! I'm sure you'll notice a difference!

Doug

Doug: Where did you get that Loctite product?

RE: torque values. Are you talking about the bushing covers that you "plated?" 34lbs.

There is a good discussion here:
http://forums.pelicanparts.com/porsche-911-technical-forum/250552-rear-suspension-reassembly-questions.html?highlight=torque

OK, I re-read your question. 87 lbs. on that puppy. Again, according to Haynes.

Thanks Milt. I think the suckers took 887lbs of force to get off.

einreb on this board has removed/re-installed these more times than I can count (I can only count to about 7). PM him if you have questions, or need suggestions. He might be able to give you a few pointers.

I bought it from www.mcmaster.com . I read in a much later thread that Tyson Schmidt was doing the same thing, which was validating for me.

Here is some more info about the products. At mcmaster, they have 767 Loctite products. Look under threadlockers.

**** I used 638
Description: For nonthreaded metal cylindrical parts such as shafts, hubs, bearings, bushings, splines, and pulleys. They prevent corrosion and fluid leakage between surfaces, resist most chemicals, allow reuse of slightly worn parts, and provide better strength than shrink-fit and press-fit assemblies. Come in bottles.
603™— High strength and contaminant resistant. Fills spaces up to 0.005" dia.
609™— High strength and low viscosity (125 cp). Fills spaces up to 0.005" dia.
620™— High strength, high viscosity (8500 cp), and high temperature. Fills spaces up to 0.015" dia.
638™— Maximum strength. Fills spaces up to 0.015" dia.

To add a bit of background. I just didn't like how hard it was to make the fit "perfect" with the shims. If they weren't tight enough, I was afraid the race would spin, but when they were too tight the shim stock would crumple on me. Also, the thin shimstock is razor sharp, as you all know. All in all, it was a PITA. The use of this retainer product eliminated further blisters from my hands related to twisting the races on and off (yep, I'm a wimp). I guess I have computer user - white collar hands.

Once it was set, I was very confident that I had a very well installed race that was nearly 100% concentric with the a-arms or torsion bars.

After 1.5k miles, so far so good!

Doug

Thanks Doug!

After acquiring the aforementioned blisters during this project, I came upon the "strap wrench" revelation to do the twisting. Not only do you have a notably larger amount of torque with this cheap & handy device, but you save your pretty, computer hands from manly carnage ;)

http://forums.pelicanparts.com/uploa...1113693494.jpg

I've been experimenting with the use of JB weld instead of shims to secure the races. Some customers have tried this method with good success. My initial results have been very positive, it is certainly easier to install than shims.

If further testing proves positive, this is going to become the standard for installation.

In the mean time, I am recommending the use of a penetrating thread locker (designed for use after parts are assembled) to be applied after the shims are installed, and wicked into the shim area. An example is loctite 290 or devcon superlock 2290.

Chuck,
Doesn't the JB Weld installation run the risk of putting the inner races off center to the a-arm? Maybe because the a-arms only rotate through 5 to 10 degrees of operating range it doesn't really matter? My concern was aligning them in the chassis, so they are more or less "friction-less".

That is the main reason I chose to use the shim + bearing retainer solution.

Doug

How many .001" would make a difference? I know we strive for perfection, but when you look at the bushings that came out, I was off center by multiples of .125".

Also, the urethane will deflect a few thou, I would think. As long as we're not filling huge gaps, I've got to believe we're "close enough for horseshoes" as far as concentricity.

What are the chances of finding the Loctite wicking formula in Dallas?

mcmaster will ship overnight to most places in the US. You may be able to drive to their retail center?

I agree that a few thousandths probably makes no difference. However, I did have a hard time with a "crash free" tub making the a-arms aligned even using the ER control arm mounts.

Doug

Muffinman ( and others):

I use an identical strap wrench to get the oil filter off our cars. Other tools are metal and the handle comes awfully close to the body lid edge...maybe causing scrapes.

This tool is the ticket for filter removal...and once you buy this cheap tool...it comes in handy for so many other things compared to buying something that is labelled a filter-removal tool.

- Wil

I have shared this concern and it is the reason I have resisted an adhesive-only approach. But the poly jacket does accomodate some minor misalignment, that is one reason it is there.

So far all indications suggest this is a theoretical concern that doesn't seem to be problem in practice.

Ed, McMaster does carry the penetrating loctite 290.

Hey Chuck...I've been thinking about going to your setup shown above...is there any reason I couldn't TIG the races to the pivot arm on the very end provided I didn't interfere with the poly-jacketed piece?...Like keep the welds small so stuff can be slipped past them? If I knew specifically what the race material was I could get the appropriate filler rod to mate mine to the arm.

Thanks...
BG