Welding Rear Springs

8EL

Senior Member
The rear spring on my 31 coupe has been worn against the axle housing leaving a divot on the outside of the spring eye. This could be easily welded with a low hydrogen rod, but what effect might it have on the metallurgy of the spring?

The spring is otherwise serviceable and given the cost of it, I intend to reuse. I could leave it as is, but would like to reapply the material lost. Has anyone attempted this type of repair? Photos attached......
 

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Do yourself and any future owner a favor. “Replace the Spring”.

Model A Ford’s suffer from the Shade Tree Mechanic problem. In my opinion, this would be a good example of that.

Do it right the first time, job done, you can move on to other problems.

Brakes, front end, springs, shocks, tires and wheels. These need to be right.
 
Don't weld on it, springs do not like heat. Just run it as is or replace it. New springs are not really that expensive or there are still a lot of serviceable used ones around
 
You can replace that main leaf for about @150.00 in California, with a new leaf. Take the old one with you to the spring shop. Get the same thickness and length. I just did a front and had the eyes reversed and new backing, along with removing a leaf for about 200 dollars at A1 Spring in Oakland.
 
That wear spot doesn't effect the use, only the looks. If this is the only defect, you can repair it by filling with an epoxy. Use an epoxy that has a metal filler that will make a tough repair. Make sure to prepare according to the epoxies instructions for proper bond.
Do not weld it as it requires procedures that pretty much most welding shops have no experience with! Your money would be better spent on a new/used one or a cosmetic repair.
 
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8,

It took 90 years of hard service to create that divot. It's going to take a lot of viagra to make that spring work again. Find another.

My $.02, jb
 
Yes you can weld it - If you also have the ability to also temper it back to its original specs.
Yes you can "bondo" it so it looks new - the wear isn't in a spot that will cause failure.
In the end you'll be ahead just hitting up local club members or a swap meet for one in better condition. But first address the worn parts that caused it to rub.....
 
I would replace it. Having a spring malfunction on a trip is no fun.
Change it so you don't have to worry about it.
 
So most springs are made from as far as I know 5160 high carbon steel. In the case of welding broken half's together, It can be welded ( have seen this) but careful attention to applied heat is essential. Cool it to fast and it will become brittle, or to slow and the annealing result will leave it soft and it will deform under load. This repair is not mostly structural and given what I have learned about this particular application, wearing against the axle housing is pretty common. Therefore I was asking if anyone had previously made such a repair and was looking to compare notes.

The load on the spring is downward, where most force is being applied to the top of the eye therefore I do not believe that it's strength has been compromised.

I thank all of you for your opinions, but I have to say that I find it somewhat insulting to be referred to as a "shade tree mechanic", and to "do it right the first time". I have spent $3,400.00 in parts on this brake / rear axle rebuild to insure it is correct. I do first class work, and have done so for the last 47 years, this job will be no exception. Thinking outside the box has afforded mankind some of his greatest successes known.

Thank You
 
You can do whatever you feel like. It won't hurt to leave it as is or fill it with anything. JB weld, braze, weld etc.
 
It's interesting the wear is on the spring eye. I have two axle housings here with big dips worn out of them from the spring hitting..
 
I would replace it, for the reasons previously mentioned, and because of the wear on the spring.

I've never seen a spring wear like that, but have seen several rear axle housings and front axles wear due to spring sag. I'd question the spring and whether its really serviceable. It is likely not the proper metal due to the sag and de-arching that allowed it to touch the axle housing for so long. The wear on the spring is not normal.

The ability to weld is one thing and even if it could be done, I think this leaf is bad.
 
The spring must have lost its arch or it wouldn’t be rubbing the axle. It needs to be at least re-arched. I replaced mine because it lost its arch and was rubbing on the front axle.
 
The spring has not lost it's arch, the bushing wore out in the spring eye and perch allowing them to rub on the axle housing. I replaced the axle housings as they were wore through the bushing into the casting. I have re welded the divots with lo-hy rod DC reverse polarity to provide for a flat weld with minimal penetration and see no stress cracks, allowed to cool at ambient. Heat added was minimal. See no reason not to put in service, Heny's steel as expected is quite high quality as can be determined by characteristics noted while welding. I will advise if failure ends up being the case, but I doubt it...pictures attached.
 

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I've never seen the spring wear, only the axle housing in our neck of the woods, in my lifetime.
So I can see why you got the responses you did.
 
The eyes of the spring are functionally not part of the car's suspension, so concern about ruining the heat treatment is negligible. However, the eyes of the spring are structural in nature. If the eyes did not fail with their untreated wear, I doubt they will fail after welding.
If the worn spring was on my Model "A," i would replace that leaf as a minimum or the replace the hole spring.
 
I find the claims interesting that state they have never seen such wear as has been realized on my machine before. From a recent post "Rear spring perch fix procedure", the shackle has failed leaving the weight of the car to be born against the axle housing exclusively. In the photo given it clearly looks to me that the spring eye is being worn in the same manner as mine, why would it not?

I am also curious why Bob Bidone agrees that after welding the spring would not fail, he would replace it any way. I agree with Bob in his assessment of the impact the welding process would have on reliability. Also as can be seen from the photos I submitted, one will be unable to discern after painting the repaired spring from new, why then would you replace it any way?
 

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