Spring Perch Troubles

chrs1961815

Well-known member
I am in the process of redoing the brakes and suspension on my roadster and I have run into a problem. I cannot get the nuts off the botton of the spring perches. The shackles have been removed, so there is nothing in the way. I tried a wrench with a pipe and eventually an impact wrench - it did not even budge! I have tried heat and penetrating oil to no avail. What should I do?
 
I usually heat stubborn perch bolt nuts with a rosebud until red; then hit them with an impact gun; always come out.

Getting the perch bolt out of the axle is another subject.
 
If you heat nut to a dull red as Rich says the impact should bring it off. I would use new nut going back together.
 
You could try the heat and quench method.
If the perches aren’t bad and need minor fixes like shackle bushings they may be able to be fixed in place as long as they are tight within the axle and wishbone. I assume there’s no remnants of cotter key left even they I’ve sheared if many . Sometimes you have a stout one!

Heat or heat quench, penetrant. Impact , to remove .
Larry
 
I usually heat stubborn perch bolt nuts with a rosebud until red; then hit them with an impact gun; always come out.

Getting the perch bolt out of the axle is another subject.

What is a rosebud? I don't think you mean the flower.:confused:
 
Rosebud is a reduced heating tip for oxycetalene torches.
I have typically used one for doing lead work for body panels.
 
Rosebud is a reduced heating tip for oxycetalene torches.
I have typically used one for doing lead work for body panels.

Called a rose-bud - but think of a flame pattern more along the lines of a dandelion "gone to seed."

A "suffuse" flame, broad spectrum, for heating wider areas to less degree. Lots of heat, lots of gas used, but widely applied.

As in doing lead body work. Or bell & spigot plumbing. Even sweat soldering.

Joe K
 
Rosebud.
 

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As soon as you get the bolt off melt some paraffin wax around the base of the perch - you are going to need all the help in getting them out of the axle. This where the real fun begins!
 
I usually cut the head and threaded portion off leaving a "slug." THEN I use the 20T press and a cold chisel/drift cut off short and slightly smaller in diameter than the slug. Press with MINIMAL heat applied to the axle.

Somewhere in the Ford literature Ford says to NOT heat the axle prior to straightening - and for steel this grain size transition point typically happens around 400F. Most welding of steel is best done between this temperature and the transition temperature of about 770F. So I stay below 400 using welder's temp crayons.

The slug is pressed out doing minimal compression - the tool doesn't "mushroom" itself, and you can re-do the attempt at increasing levels of press - keeping control of the process.

Thermal cycling and Oil of Wintergreen is your friend. Lots of Oil of Wintergreen in PB Blaster.

Heh. Saying this reminds me of the book "The Sand Pebbles" and the movie with Steve McQueen.

Ho-mang (Holman)

Joe K
 
Why are you removing the perches??
Paul in CT

I've done a front end both ways. It usually depends on if the bushing for the shackle is worn through into the spring perch.

If worn through even this can be remedied by a good grinder, welder and copper heat sink. You grind out a "slot" eliminating 3/4 of the worn through part, then using the copper chill you build up again using a TIG or MIG. It's not a big deal and not that hard, the biggest challenge removing the chill after the welding/shaping is done with a burr. Some use a 3/8" brass pipe with a slot cut out of it. (You're only looking to back up a third of the diameter.)

Sometimes the balls for the shock absorbers have been cut off - even these can be replaced by welding.

And sometimes you just want to start over for "nice." I had one I replaced where the dog-bone shock absorber link had worn into and ruined the little "pad" which prevents the shock shackle from "tilting" and makes a better seal on the original shackle.

If you remove the spring perch, you probably want to at least check the axle beam "straightness" using KRW type rod indicators. If the holes all line up and the 7 degree angle of the kingpins is maintained, you're probably good to go.

Model T axle below, but the tools and the principle are the same.

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Joe K
 
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Still nothing after several rounds of heat and water. I dropped the front of the axle and tomorrow I am going to disconnect the radius rods from the transmission. Maybe a better angle would help.
 
If the nuts are that tight, I can't imagine how tight the perches must be in the axle. I've had to drill them out before, and that of course ruins them.
 
Now that the axle is out, you will be able to get more pressure on it. Try jumping on the spanner or putting a pipe over it. The worst that can happen is you'll twist the bolt off but it sounds to e like you'll have to ruin it anyway to get it out of the axle. Time to show it who's boss!
 
Rosebud is a reduced heating tip for oxycetalene torches.
I have typically used one for doing lead work for body panels.

This is what I have known as a "rosebud" for fifty plus years; maybe a regional thing?

Doing a little heating today and as you can see there was no "reduced heat" around the two rosebuds we were using which resulted in nicely pliable axle.
 

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Doing a little heating today and as you can see there was no "reduced heat" around the two rosebuds we were using which resulted in nicely pliable axle.
So much for Ford's instruction to straighten the axle "cold" as heat upsets the metallurgy.

Come to think of it, you're not straightening it, are you?

How can I find fault with a technique which has been done by Rodders since the invention of the "Hot-Rod."

I can't say I have EVER heard of anyone losing an axle end after the modification.

We'll just chalk it up to "good metallurgy" and the "wisdom of Ford."


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Joe K
 
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When my brother and I were straightening axles it was easy to tell which ones were heated, it took 1/2 the pressure to bend them compared to ones that didn't get heated red, and there's little bounce back
 
We do all axle straightening cold before we proceed to the heat work shown in my previous post.

Still surprised you are having trouble with the nuts; usually the easiest part of the process.
 

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