Rear Spring adjustment

[sphooch]

Does any one have any helpful hints on how to center the rear spring , Its a 31 roadster and just noticed the spring is off. it needs to be shifted about 5-16 of an inch toward the passenger side. the body is off the frame , were the frames come together at the rear , someone worked on it . The rivets have been removed and replaced with bolts.I'll want to center the spring and reinstall the rivets. Some helpful know hows will be greatly appricated.. THANKS THE HOOCH

[Patrick L.]

What does the spring center bolt and rear crossmember look like ?? The head of the center bolt should be square and fit into a square in the crossmember.. I think thats what you were asking.. Over all these years you never know what has been done to these old monsters.. Maybe yours has a wrong crossmember or some such thing..

[d.j. moordigian]

Be real careful...the center bolt that holds all the spring leafs together could be
broken...when you loosen the 4 nuts on the spring clamp. Use 2 "C" clamps on the
exposed leafs, then make sure the bolt in the center of the spring is good.

[sphooch]

the square bolt in the center of the spring is not sitting exactly in the center of the square oppening. I measure it to be 5-16 of an inch off to the driver side. Do you know if i loosen the 4 nuts on the u- bolts , with the c- clamps on the springs, would I be able to shift the frame over??? or should I remove the spring to check for a broken center bolt?? thanks

[d.j. moordigian]

If the center bolt is broken, the c clamps will keep some of the leafs from flying out.
Do you know for certain that the bolt is good?

[700rpm]

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As long as the body's off, I would suggest dropping the rear end, getting a spring spreader, taking the rear spring apart, cleaning and lubing it, and putting a new bolt in. This is dangerous business. Do a search here on previous discussions about handling the rear spring. There's lots of info.

[CarlG]

Mine had a round head bolt -- both front and back -- obviously been changed out at some time or another. I put a new spring in the front, but the rear one is still like that.

[Patrick L.]

I guess I'm unsure of what you're saying.. Is the spring bolt NOT in the frame hole and off to the left ?? Is the frame hole not located correctly ??
If you start to loosen the 4 u-bolts,, you'll find out if the center bolt is broken or not.. If the leaves stay together the bolt is in one piece.. If the leaves start to separate then the bolt is probably broken.. The spring/leaves need to be treated with respect..
If the spring is just not properly located then just loosen the u-bolts and pry the spring over until the bolt will fit in the hole and tighten everything up..
Like said,, it can be a good thing to pull the spring apart and grind/clean/grease the leaves and re-assemble.. I leave the main leaf in place and just remove the others.. A couple c-clamps will allow the leaves to be removed safely and some ' all-thread ' to put them back together..

[ctlikon0712]

If he relplaces the bolt, what type and grade should he use? Would a grade 8 be too hard and brittle? Just wondering.

[Tom Endy]

The rear spring can be lethal. You want to give it due respect:

My suggestion is to use a proper spring spreader to spread the spring while it is still in the car attached to the cross member of the frame with the two U-bolts. It will then be safe to remove the shackle bolts. With the rear axle assembly out of the way collapse the spring spreader and remove it. The spring then is no longer lethal even though there is still some minor tension remaining. remove the two U-bolts and remove the spring from the car. From this point on the spring is no longer dangerous. Put a C-clamp on either side of the center bolt to hold the leaves together and remove the bolt. Remove the two retainers on the sides. As you release the C-clamps the the spring will come apart.

De-grease and bead blast (or wire wheel) the leaves. Grind the witness marks out of the tops of the leaves where the leaf above dug into it. Round off the bottom edges on the ends of each leaf so they will no longer dig in. Spray the bottoms of each leaf with Slip-Ease as you assemble the spring.

Most Model A suppliers sell a replacement bolt (and nut) with a square head, that is twice as long as needed. This extra length will aid in pulling the leaves together during assembly. You can also use C-clamps to help pull the leaves together. When fully assembled cut the extra length off the bolt and peen the bottom end over. make sure the square head is centered straight. Wipe the excess Slip-Ease off the sides and paint the assembly.

To install the spring back in the car put a chalk mark down the sides of the spring at the center bolt. Put another chalk mark on the sides of the cross member where the square hole is. With the aid of a jack or with help hoist the spring into place lining up the chalk marks. When the spring is seated move it back and forth sideways to ensure the head of the bolt went went into the square hole in the cross member. Install the U-bolts.

Put the spring spreader back in place and spread the spring far enough to be able to connect the rear axle assembly up with the shackle bolts. When the shackle bolts are secure remove the spring spreader.

This is the safe way to go about the task.

Tom Endy

[sphooch]

thank you so much . sounds like good advice . THE HOOCH

[bogiediver]

Sorry to bring up an old thread - but thought it was better than starting another...

I also have a Roadster. The car appears to be sagging low, when looking from the front, on the driver's side - by a good couple of inches. No shocks on the car. It was suggested to me that a rear spring that has shifted the center bolt to the passenger side of the cross member centering hole could cause this.

sphooch -
- was this the case with yours - sounds like your rear spring shifted toward the driver's side, so did the passenger side appear to be sagging?
- If so, did shifting the spring back to center correct the sag?

I have not crawled under to look yet - but I'm guessing someone here can confirm or deny this in about 2 seconds - I was told the u-bolts go thru holes in the cross member - correct?

It was further suggested to me that if I loosened the 4 nuts on the u-bolts (not necessarily removing them); put a 4x4 (or other substantial material) under brackets where the bumpers are mounted and jacked this to raise the body (while the wheels remain on the ground), I could move the cross member back to center over the spring. Then tighten the u-bolts and all would be good.

Another suggestion has the sag resulting from a shifting of the front spring to the passenger side. And that the same process of loosening, but not necessarily removing the spring, and shifting back to center and tightening could level the car out...

I understand the risk if the center bolt is broken - seems like if that's the case, it would be apparent as the u-bots were just starting to be loosened.

Thoughts?

[oldmanandakid]

The new rear spring waiting in our shop has a round pin not a bolt. Can I assume the pin was was pressed in and will be an OK fit in place of the square bolt head?

[Tom Wesenberg]

Originally Posted by oldmanandakid

The new rear spring waiting in our shop has a round pin not a bolt. Can I assume the pin was was pressed in and will be an OK fit in place of the square bolt head?

It must be a round head on a threaded bolt, isn't it?

[oldmanandakid]

Tom---I just went out to look and it is a straight sided round pin (about 1/2") on top and is threaded on the bottom with a hex nut.

[Mikeinnj]

The rear and front x-members should have square holes to nest on square headed spring center bolts. Sometimes the holes get wallowed out of shape from wear or have been modified. Some spring shops/suppliers assemble their springs with a round headed bolt which should be replaced with the correct square headed bolt.