Rear Spring

[jhowes]

I am now putting the rear spring together and the question of the strength of the center bolt has arrizon. Is that a grade 8 bolt because I am nervous bringing it down to its final resting place. It seems like a lot of pressure on that single bolt. Just trying to save my life, thanks in advance. Jack

[Russ/40]

Well, consider the spring well restrained when bolted into the rear member. When out and sitting around, it is wise to wrap a chain around it. Especially if it has been removed not knowing the condition of that bolt. A quality bolt from one of the suppliers for that purpose is warranted.
I applaud you on your caution, very much warranted.

[100IH]

First, have you checked to see that the had of the bolt fits into the square cutout in the ea crossmember? Keep the head in position as you tighten, not after, We have to assume that the bolt is new because the x-cess is going to be cutoff after it's fully tightened and then the end peened over so the nut won't loosen. When you get to the final stages of tightening, put some c-clamps near the bolt to draw up the leaves. This will avoid excess strain on the bolt toward the final tightening. All of this should be done with the spring on the floor. Final assembly to the rear axle assy. with the spring clips installed and using the spring spreader, the graphite and/or grease will also lessen the stress on the center bolt.

[jhowes]

Thanks to both of you for your advice. I am using straps and C clamps, the bolt is new from Snyders I didn't know about the piening after all is assembled. Jack

[redmodelt]

Yes too peening. Once the nut is drawn up and the excess cut off, peening turns the bolt into a rivet. The bolt is only there to keep the spring pack together, the U bolts and clamps do the rest.

[ursus]

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While on this subject, what is the best way to install a rebuilt spring when the rear end is out? It seems like a struggle to mount the spring in the crossmember before installing the rear axle assembly so why not mount the spring to the rear axle first then roll it all into place together?

[jhowes]

Ursus; That's exactly what I am doing. I mounted the main leaf with a spring spreader and then one leaf at a time with plenty of nylon straps and clamps . In the future I would use a threaded rod until the leaves were close enough together to remove and replace with the 8 inch bolt that the vendor's sell. Jack

[Tom Endy]

The rear spring on a Model A Ford can be lethal. It should never be removed from the car while attached to the rear axle assembly, yet people do it all the time. The only thing preventing the spring from exploding is the 3\8" center bolt that was never meant to hold that much tension even when new.

The safe way to deal with the spring is to first install a proper spring spreader to capture the tension in the spring, remove the shackle bolts and lower the rear axle assembly out of the way. Next collapse the spring spreader and remove it. The spring is then no longer lethal; it can be removed from the frame of the car and taken to a work bench for disassembly. There is negligible tension left in the assembled spring. A C-clamp can be used to hold the remaining tension to aid in removing the center bolt.

The new center bolts most suppliers sell are twice as long as need be for the purpose of easy assembly. Once the leaves are drawn together the extra length should be cut off and the end of the bolt peened.

Attached are two articles that deal with the rear spring.

Tom Endy

[Tom Wesenberg]

In addition to what Tom just posted, be sure you use quality C-clamps, NOT Harbor Freight clamps.
Some H/F tools are OK, but not the C-clamps, which have the strength of a dried cow pie.

[jhowes]

How did Tom know that I had Harbor Freight clamps? Jack

[Joe K]

MUCH easier to deal with the spring as part of the rear axle unit. Probably safer too.

When I took the spring off my axle, I used 3x3 oak section "strongbacks" around the pumpkin. Blocked under the spring ends such that as the spring flattened, it would hold the spring at a proper height to loosen the shackles.

Two pieces of all-thread, washers & nuts, one on either end of the strongback - tighten evenly until the shackes loosen. Be sure to leave enough all-thread available for "full release" position. (I simply didn't cut the 3' pieces of all-thread.)

Today I would do similar with a 20T press - same blocks but no strongbacks.

Joe K

[Joe K]

There is negligible tension left in the assembled spring. A C-clamp can be used to hold the remaining tension to aid in removing the center bolt.

Reports on this forum generally agree - but be careful of those 10 leaf "E" springs which are under the pickup trucks and certain commercial 103" wheelbase.

My own spring was being held in the vise. I found the nut and carefully ground off the peining over. I then clamped it using an 8" welders type clamp and removed the nut.

The nut had been undone, the bolt removed, and I had begun to undo the clamp when the spring "squirmed," flew apart, came out from the C-clamp, and the large leaf flew skyward and left marks on the dining room floor joists overhead. The other 8 leaves (one in the vise) were scattered about on the workbench like so many tree leaves in the fall and before their scattering had jumped themselves about two feet.

I was young and fortunate. And standing out of harms way through all this.

So maybe put a chain on that one too? And keep one's head and arms away from the possible trajectory?

Joe K

[Ranchero50]

I popped my 10 leaf stack apart today. I used the frame U bolts to hold it while removing the 3/8" center bolt. I installed a 8" long grade 8 one I had floating around and used a welding clamp and a couple short chain come a longs to secure the mess. The shackles were still attached and it came apart pretty well. The bottom five held their form (thanks to the clip maybe?) and once the top five came loose to the bolt stop I knocked them sideways to unload the rest of the way. I removed them for now until i make a spreader to dismount the rest.

[Joe K]

Heh. Your method of bolt substitution.

Before seeing this it came to me after writing my spring adventure what I did wrong with the welder's c-clamp.

The error I made was in using the clamp to "let down" the spring once the center bolt was removed.

Better would have been to use the C-clamps simply to "hold" the spring pac together, remove the center bolt without moving anything - and replace it with a Grade 8 all-thread (IIRC, rating on bolts is done by grade, rating on nuts is by alpha letter, what is the rating system for all-thread?)

With a generous length of all-thread and starting "tight" one could let down a spring in virtually perfect safety - and no risk of leaves bouncing off one's forehead.

Hindsight is 20-20, of course. And your 8" bolt is/was "reading glasses."

Joe K

[Ranchero50]

Originally Posted by Joe K

Heh. Your method of bolt substitution.

Before seeing this it came to me after writing my spring adventure what I did wrong with the welder's c-clamp.

The error I made was in using the clamp to "let down" the spring once the center bolt was removed.

Better would have been to use the C-clamps simply to "hold" the spring pac together, remove the center bolt without moving anything - and replace it with a Grade 8 all-thread (IIRC, rating on bolts is done by grade, rating on nuts is by alpha letter, what is the rating system for all-thread?)

With a generous length of all-thread and starting "tight" one could let down a spring in virtually perfect safety - and no risk of leaves bouncing off one's forehead.

Hindsight is 20-20, of course. And your 8" bolt is/was "reading glasses."

Joe K

After reading your earlier post I knew I wanted to keep the stack held together. All thread is typically grade 2. Nuts are as well. They want the nut to strip before the higher quality bolt breaks. I loosened the clamp and tapped the stack so the leaves would separate gradually. I sweated it for sure but it worked out OK.