Technical Report: Bronze Spring Bushes

[Moseso]

Say what you will about rubber, or nylatron, or urethane rear spring bushes -- they won't do THIS to you....

There has been a burgeoning, and annoying squeak from the right rear of the car. I determined a few days ago that it was surely coming from the spring shackle. So -- today -- I began to take it apart for some lube action. (The oil squirted on it a few days ago had been useless.)

It's stuck in there bad....

The attached photo shows the spring and its pin removed from the shackle. Using a 14" pipe wrench, I can rotate the remnants of the shackle in its bushing -- barely. There's no way to beat it out from behind, as the frame and spare tire compartment block access.

When I can arrange two people for the job, I intend to attempt to "wiggle" the shackle while trying a lever between the frame and the shackle pin. I'm not actually encouraged that this will work.

Phase II will involve removal of the wing (for access) and grinding off the head of the shackle pin to the point where I will be able to drive it inwards out of the bushing. This will also require cutting the pin off (Sawzall?) between the bushing holder and the frame -- probably, a couple of times before I can drive it out.

THEN ----- I can ream out the bushing, lube the snot out of it and install a new shackle.

That's the current plan, anyway. After a couple hours under there, today, I was out of "nicer" ideas.

Commentary/ideas/tips/advice/warnings all gladly accepted.

 

[TR3driver]

IMO your first approach is likely to work. Turn the shackle so it points downward, so you can pry between it and the frame piece. A helper would be good, but I'd be trying to do it myself; with a nice long pry bar and a 'cheater' on the pipe wrench.

To cut the pin, I'd attack it with a 4" angle grinder and cutoff wheel. Unfortunately HF seems to have quit carrying the cutoff wheels with the 5/8" bore (to match their angle grinders), so I just bought some wheels from MMC. Haven't had a chance to try them yet, though.

 

[TR3driver]

Unfortunately HF seems to have quit carrying the cutoff wheels with the 5/8" bore (to match their angle grinders)

Oops, my mistake. They're listed now
https://www.harborfreight.com/pack-of-10-4-inch-cut-off-wheels-for-metal-45432.html

 

[Moseso]

Yup... Got an angle grinder -- and a small pile of good wheels.

I hope you're right about being able to wiggle it out with a helper on the pry bar. But it's in there pretty darn tight!

 

[JFeher]

Maybe if you do the other side at the same time you'll be able to lower the springs enough to get behind them and drive them out.

 

[Moseso]

Re: Technical Report: Bronze Rear Spring Bushes

No can do. The bushing/pin that's frozen is the one that's welded to the frame. The only way to get behind that with a hammer and drift is to lift the body off the frame. There's gotta be 17 different ways to solve this before I do that!

 

[hondo402000]

Re: Technical Report: Bronze Rear Spring Bushes

how about a torch and heat it up, I understood heating rust forms carbon
and releases rusted thing

just a thought

Hondo

 

[M_Pied_Lourd]

Re: Technical Report: Bronze Rear Spring Bushes

Moses,

Is this the kit with the bronze bushings and delrin washers? I have it installed on mine and don't want to have similar issues down the road.

Cheers
Tush

 

[Moseso]

Re: Technical Report: Bronze Rear Spring Bushes

Moses,

Is this the kit with the bronze bushings and delrin washers? I have it installed on mine and don't want to have similar issues down the road.

Cheers
Tush

Yes. That's the one. I thought I had everything well lubed and fit, but this one somehow got dry enough to seize. That was the point of my first sentence. The failure mode of any of the "soft" bushings won't cause this type of disassembly nightmare.

There would be a way to modify the bushing holders on the frame for zerks. No good way, that I can see, to do the same for the spring eyes. Maybe they should be disassembled and lubed once-a-year, or so.

 

[TR3driver]

Re: Technical Report: Bronze Rear Spring Bushes

No good way, that I can see, to do the same for the spring eyes.

How about drilling a small (1/16" or less, don't want to weaken it too much) hole through the center of the shackle pin, and then welding a nut on the outside to hold a grease zerk? Not that much force involved, so I don't think that would weaken the pin too much. But if it did, you could replace the pin with something stronger (like 4140).

 

[Moseso]

Re: Technical Report: Bronze Rear Spring Bushes

That's the part I was missing, oh, great engineer. I got stuck at the small hole through, which I thought I could live with, but couldn't live with the size of the hole required in the head of the pin, in which to tap the zerk. Of course! Add a small nut. There you go, Tush. They're lubricatable -- with a little modification...

 

[bobhustead]

Re: Technical Report: Bronze Rear Spring Bushes

Get the shackle out of the way by cutting thru the bolt behind the shackle. This will expose the end of the bushing. Drill several (numerous) holes all the way thru the bushing, starting with a bit about whose diameter is about half the thickness of the bushing. Drill them close together. Then repeat with a bit of equal or slightly lesser diameter than the bushing thickness, thus removing the bush a core at a time.
I have at least one more suggestion if you don't like this one.
Bob
By all the way thru, I mean outer end to inner end along a horizontal axis as the car sits.

 

[Mickey Richaud]

Re: Technical Report: Bronze Rear Spring Bushes

Folks - just a reminder: If you want to review a product or vendor, please do so over in the Vendor and Product Review side. Basil has a policy regarding posts about vendors and products, and if you're not familiar, please take a look.

Thanks!
Mickey

 

[MadMarx]

Re: Technical Report: Bronze Rear Spring Bushes

I have these bushes from Joe in my car but they're doing fine. I've greased them very good at installing and found no escape of grease from the bushes.

Good luck!

Cheers
Chris

 

[Moseso]

Re: Technical Report: Bronze Rear Spring Bushes

My apologies, Mickey, for approaching/dancing on/crossing the line. In spite of my thread title -- an admittedly poor choice, given the policies -- I don't really consider this a product review. I have nothing to report about the quality of the product. I don't "blame" the product for anything. Other than the unanticipated difficulties encountered in addressing its failure, I think it's a fine product.

This is a technical report on what could happen to other TR owners -- did happen to me. What I did not anticipate (didn't think about, really) is the pernicious difficulty that could be encountered addressing a failure of this particular design -- a trait not shared by the stock design, nor any of the other alternatives to it. I don't think this is a "failure prone" product/modification. But if it does fail, it's different.

As (probably) the first to encounter these issues with this modification, I thought this a good place to a) report it, and b) check my plans with the others on how best to deal with it.

 

[Moseso]

Re: Technical Report: Bronze Rear Spring Bushes

Get the shackle out of the way by cutting thru the bolt behind the shackle. This will expose the end of the bushing. Drill several (numerous) holes all the way thru the bushing, starting with a bit about whose diameter is about half the thickness of the bushing. Drill them close together. Then repeat with a bit of equal or slightly lesser diameter than the bushing thickness, thus removing the bush a core at a time.
I have at least one more suggestion if you don't like this one.
Bob
By all the way thru, I mean outer end to inner end along a horizontal axis as the car sits.

Gotcha, Bob.

I may get there. Though, I'm not certain I want to remove the bushing yet. My initial plans have been to remove the shackle pin in a non-destructive way, ream the bushing a bit, polish the pin and reuse them. If I have to destroy the shackle to get it out, I may <span style="font-style: italic">still</span> decide to use its replacement in the bronze bush.

Or... I may opt to get it out of there altogether. I don't think driving the bush out of its holder will be as difficult as withdrawing the pin from it.

I didn't want to remove the rear wing, but I'm beginning to think the accessibility that will provide is well worth the extra hour, or so, it will take.

 

[TR3driver]

Re: Technical Report: Bronze Rear Spring Bushes

If you want to review a product or vendor, please do so over in the Vendor and Product Review side. Basil has a policy regarding posts about vendors and products, and if you're not familiar, please take a look.

FWIW, Mickey, this doesn't seem like a "product review" to me. In spite of the title (which I took to be humorous/ironic), Moses is asking for help in dealing with a problem. He hasn't said anything about how well the product works (when it does) etc.

In my opinion (which after all doesn't really matter, this is Basil's bailiwick), this forum is the right place for this thread.

 

[bobhustead]

Re: Technical Report: Bronze Rear Spring Bushes

If you are going to use the basic parts, consider removing the piened (sp?) in bolts and replacing them with stainless. I am too lazy to look up the shear modulus, but I don't think it would be too far off.
Bob

 

[hondo402000]

Re: Technical Report: Bronze Rear Spring Bushes

In my opinion Stainless would be a wrong direction go to in, stainless steel rubbing against carbon steel would gall and seize up worse than bronze, maybe an oilite bushings would be better, but drilling for a grease fitting would be the best route

IMO
Hondo

 

[bobhustead]

Re: Technical Report: Bronze Rear Spring Bushes

My suggestion would have stainless as the pinion, rubbing the bronze, with the bronze fixed in the shackle hole.
Bob