Bilstein RSR strut top threaded rod nut removal? Special tool?

[Jim Williams]

I found the source of another thump and bump in my '73 RS look-alike's front suspension. I found that there is some slop in the mounting of the Bilstein RSR front strut at the top mount, maybe a 1/16" or so on both the right and left side. The threaded rod goes through a heim joint top mount. On trying to tighten the nut, I find that the threaded rod the nut is screwed to moves also, and there is no apparent way to hold the rod. The rod does have a keyway machined down its length, leading me to think that there has to be a way to hold it securely while the nut is tightened ((or loosened). Does anyone know if there was a tool furnished with the strut, or if there is something I'm missing?



Maybe hold the washer just below the nut with some water pump pliers?

Short of holding the piston, which turns along with the nut (and rod), I can't see any other way to hold the rod.

I thought of perhaps finding a nut to fit the rod, and filing a matching key way in the nut, then inserting a properly sized key, and then counterholding that nut. I tried one of those tools with the folding hook on the end, but all that has accomplished is buggering up the threads on the threaded rod.

[Steve@Rennsport]

Jim,...Do you have any air tools (and compressor, of course)??

Its a cinch to R&R those nuts with a 3/8" or 1/2" impact wrench.

[Jim Williams]

Originally Posted by Steve @ Rennsport Systems

Jim,...Do you have any air tools (and compressor, of course)??

Its a cinch to R&R those nuts with a 3/8" or 1/2" impact wrench.

Steve,

Yep. I have a big honkin' air compressor. 5 (real) HP, 80 gal tank, 2-stage pump, and both a 3/8" and 1/2" impact wrench.

What I'm not seeing though, is a way to counter-hold the threaded rod to keep it from spinning along with the nut I'm trying to remove. What am I missing?

[barney911rs]

You should be able to hold the rod in the fender well with your hand while tightening the nut with an impact gun on top. If not use some large vice grips or channel locks (with a rag to protect the rod) to hold it still.

[Chuck Moreland]

Jim, You won't need to counter torque the strut. Just hit it with the impact wrench and you'll be gold.

The slot in the strut accept a toothed washer that can be used to counter torque the strut. But the washer is absent on your car.

[3.2 CAB]

If you really wanted to get creative, get a BIG washer and mig a piece of key stock to it, then on the other side weld a nut, flat on to the washer. This way you can slip the "tool" down the shaft, then hold the nut side with a wrench, then use the correct size box end wrench to loosen the big strut nut. Talk about overkill, o-well. Good luck!! Tony.

[Jim Williams]

Steve, Chuck, and John,

Thanks for the suggestion of the impact wrench. I had some doubts, but I gave it a try this morning, and spun them both off fairly quickly. But John, I never use a impact wrench to *tighten* anything. Maybe there are some folks that can tell how much torque they are applying, but I don't trust this method for torquing, only untorquing.

Tony,

Glad I didn't have to get creative.....

I found the problem with the slop in the top of the strut connection. There is a large washer (spacer if you insist), that lacks just a little over 2 mm in thickness being enough to take out the slop when the nut is tight. I used a dial indicator mounted on the fender, measuring the top of the shock rod, and loading and unloading the suspension using the lift. Luckily, I found a couple of washers (matching pair, one for each side) measuring 2.5 mm in thickness, that I will now need to add to the washer already installed at the base of the threaded rod just under the heim joint.

[3.2 CAB]

Jim, glad to hear you got it done. The others had already stated the easiest way, so I was just giving you a "Rube Goldberg" possibility!! Good luck!! Tony.

[jimmcc]

Jim,

I've never had any problem using the air impact to retorque the strutt nut and that's the way I was taught to do it. Spin it up real quick and it will torque down in an instant. No need to hold the gun on it for a long period.

Glad to see you got the rear end problem worked out. I've been busy and haven't followed the thread but will go back and read your solution.

Jim McCullers

[barney911rs]

Jim,

You're reply confused me until I went back and read what I wrote. These old timer moments are happening way too often.

I concour with what jimmcc said. This is not a nut that is real sensitive to torque. You just want to make sure it's on using the old German method. "Good-N-Tight"

[Jim Williams]

Here's a follow-up on the looseness at the top strut mount for anyone that might be curious. Between the loaded and unloaded front suspension strut, the amount of play was measured like this.



2.11 mm of play; metal against metal whenever the the road conditions loaded and unloaded the suspension. The nut was already as tight as it would go. The solution was a thicker washer, but an added one of the right size would fix it. First photo is a "before" on the right side, second is an "after" on the left. The small lower washer was the fix.




The "washer" under the strut nut is actually a locking device for the nut. I should have recognized it for what it was, but until it was out and I saw how thin it was it didn't ring a bell that it was designed to fit into the channel in the threaded rod, and get it's body folded up against the sides of the nut to prevent the nut from backing off.



The second "washer" had it's tab sheared off, and the one with the tab had not been folded up as it should have.

Anyone know where these lock-tab washers can be found?

[jimmcc]

JIm,

The dealer has them and so does Smart Racing. From SRP they are about $1.85 or so each if I remember.

The camber plate is one from Racers Group and looks identical to what I have on my 930 which was built in 1997. There is a spacer that fits between the top of the shock and the bottom of the camber plate bushing which looks some what like your third photo.

When you spin the top nut back on using the impact when it torques up the shock shaft will spin like when you tried it with a wrench. At that point the nut is tight then you can bend the tab up on the locking nut.

Jim

[Jim Williams]

Jim,

The thick spacer on the top of the shock rod, on my setup, lacked just over 2 mm of being tall enough to lock the shock rod firmly into the hole in the heim joint. I guess the car must have been driven that way by the PO since the RSR strut and camber plate were first installed, along with the attendant racket it produced.

I have been unable to find an online diagram of the part in order to find a source or a name or part number. I know of course that Bilstein makes the strut, and TRG I believe is where the PO bought the camber plate. But the Bilstein website is not very helpful, and I have no "dealer" name, and the TRG site doesn't any longer appear to show the camber plate.

In the meantime I have used a spring washer, and will probably give the nut a short burst with the impact wrench after I give the car a brief road test to make sure the suspension noise is gone.

[jimmcc]

If my recall is correct Jim the spacer/bushing came with the camber plate from TRG. Unfortunately I do not have a part number or spec sheet on it. Give TRG a call. I've found they keep track of their product origins and can sometime locate a part if requested.

Do you know the manufactirer of the strut brace on that car? I like the way it ties into the center of the strut rather than the mounting bolts.

Jim

[Jim Williams]

Jim,

Not sure on the strut brace, but I think it came from TRG as well. The PO of my car had most of the suspension work done by a body shop, and doesn't seem to remember where a lot of the aftermarket add-ons were purchased.

Here is a photo I copied from the TRG site probably a year or so ago.