rear spring center bolt

A

aichord

Member
I have a 1929 model a pickup. The rear spring has a bolt with a round carriage type head on it. i would like to replace this bolt with a square head bolt. I already have the rear end pulled and lying on the garage floor with the rear spring intact. Is there a way to remove the center bolt and change it out without having to release the rear spring from its shackles. I have already placed the C clamps on it and have a short peace of high load chain wrapped around it.
The reason for the bolt change is the round head of the bolt is allowing the spring to move out of the hole in the cross piece and shifting to the right causing the whole truck to lean on the drivers side.
 
your going about it right, just make sure the clamps are big and usa made, not the harbor freight ones
 
Yep, NEVER use Harbor Fright C clamps for anything more than a paper weight. I used one to pull a slight bend out of the edge of a thin piece of steel on my riding lawn mower. The C clamp twisted like a wet noodle. What a piece of crap!

BTW, now is a good time to clean and grease the spring leaves.
 
check the squareness of the hole. It should have steep sides the full thickness of the cross member. If not, weld it up and file as necessary
 
FWIW: Just good to know experiences to share.

Good to know information "before" installing or reinstalling a spring rather than "after".

1. If you remove the rear spring to change the center bolt, this may be a good time to check if there is wear on "all" spring leaf "tops".

2. Often, after time, one finds that the bottom, outer sharp 90 degree edges of spring leaves dig & wear a recess in the tops of the adjacent spring leaves down below.

3. The spring leaf "top" wear usually stops abruptly after time & causes a 90 degree "stopping" point for the sharp bottom edge of the leaf above.

4. It is similar to the adjacent top leaves begin to flex & slide outwards to a certain point until they encounter a "brick" wall ..... but, it is a 90 degree "steel" wall on the adjacent leaf down below.

5. When one hits a bump, spring leaves flex & slide outwards to a certain point ...... then stop flexing at the steel wall thus causing jolts & a much rougher ride.

6. The fix is to remove the 90 degree indentation on tops of leaves with a side grinder as well as easing the outer bottom sharp 90 degree edges from the leaves on top to totally eliminate this steel wall & prevent this wear from ever happening again.

7. Even if providing a new spring, easing the outer leaf bottoms will prevent future wear in tops of leaves.

8. Spring covers help to keep highway splashing water from washing away spring petroleum based and/or spring graphite lubrication as well as prevent sand & grit from entering between spring leaf joints.

Just experiences to share in doing something only once in a lifetime.
 
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Never try to change the center bolt without releasing pressure from the rear spring by using a spring spreader and then removing the shackles, but only done while the spring is mounted in the chassis. This rear spring can be deadly if the center bolt breaks or is removed, without the U-bolts in place.
 
Harbor Fright tools are the paper plate of tools... Might work for easy salad tasks but I'd not want to cut a steak on them....
 
Thanks guys. I have changed the bolt and all went well. Checked all the plates of the spring and they look good. Now I just have to put the rearend back on the frame. Shackels are another job for another day I won't attempt them without a spreader.
 
Glen in Hillman MI said:
You do not have a center bolt problem, you have loose u-bolt problem.
Must be as tight as you can get them. 100 lb. or more
Click to expand...

He "had" a center bolt problem because it was a carriage bolt for which the head couldn't nest in the square hole of the crossmember. In other situations, yes, loose u-bolts can cause a center bolt to break.
 
The spring can be a stinker to get into place at times, but, if your fingers are small enough you can feel the center bolt slide into the hole.
It hard to over tighten the u-bolts, just don't slide the car off the jack stands. [smiley face]
 
you may find that the rear spring wants to bind on the sides of the rear crossmember. I use a bar to get it into position as I raise it with a floor jack under the melon. Bob
 
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