Spring perch removal ?

I just did this. Really stuck. Kroil, Heat, big hammer. Took three days but finally out. Perches are not reusable
 
Never heat the axle past the point where oil start smoking you will ruin the axle's metal. This will make it very soft.

I had a pair of perches that would not move.

Keep in mind I have this big vice and tried all the common things. Though kroil I never bother with as it never actually soaks through if they are really stuck. That is another story.

Not long before this I picked up a pile of tools insanely cheap at a garage sale. In this pile was a long throw automotive air hammer. So I thought, lets give it s try.

I cut the end off a chisel tool and put the nut on the end of the perch. Pulled the trigger and much to my surprise after a short bit it moved, slowly. Got it down and pulled the nut off, keep in mind it was still very very tight. Pushed it through. The end was mushroomed a bit, but the original nut still fit on it. The other side worked the same way.

A KEY part of this, I have a vice that is around 100lbs. Two people had to lift it on the bench. This did not allow the axle to move even a small amount. If you can not solidly back the axle while hammering it will not work very well.

Good luck.
 
Folks have been dropping model A axles for over a half century. Many of those dropped axles are still in service. You cant hurt the axle by heating it unless it gets so hot it bends from it's own weight. Cherry red to a dull orange is about as hot as you can go. Bright orange or yellow is way too hot.

You can heat the perch hot enough to see some red starting to show but you don't want to hit something that hot. Heating and letting it cool will break some corrosion bonds and it can even be allowed to cool off before pressing on it. A person can try heating it to 250* F and start pressing but it can be a lot hotter than that and still keep it's bond grain intact. Start out at a decent temp and the results will be better. I've welded a piece of steel strap over an old perch nut so that it can be threaded down on the perch till it bottoms against the welded strap. A person can hit that with a hammer or press on it if they are careful. Backing up the axle is important but a person doesn't want the back up tooling to mar the axle.
 
i use a muffler air hammer with a flat punch end. I screw the nut on perch Enough to keep the punch centered.
Heat the axle and use the air hammer. Often the perch comes out ok.

By the way the Model A roadster in my Avatar has a heat bent dropped axle.


John
 
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