Radius rod is too long

[Russell Reay]

I recently replaced an axle shaft. I did not intend to totally remove the radius rod, but could not untangle the brake actuating arms w/o first removing the RR. Upon re-assembly I find the RR to be about 1/2" too long, ie the RR hole does not correctly line up with the front bolt. Since none of the components have any flex (or better not !!) my options are limited. I loosened the backing plate bolts and disconnected the spring which gained me about 1/4", but still no go. I can insert a bar between casting bosses on the bottom of the transmission and pry against the front of the RR, but there isn't enough give to achieve the objective. Any suggestions?

[nkaminar]

Take a tape measure and measure the distance from the hole in the front to some point on the rear axle like the spring perch. Now do the same for the other side. They should be equal. Plus, both rear wheels should point straight ahead. You can check this by sighting the tires to the front wheel or use a tape measure or other tool like you would use to check the toe in on the front. Also measure the distance from the banjo to the backing plates. That should also be equal.

The radius rod has not changed length. There is something wrong in the back. Careful measurement should point out the problem.

On a Model T it is not uncommon for the rear end to be bent. When they were $5 each or free, they were used to pull stumps by tying a chain to the differential.

[GRutter]

If not done already, take the weight off of the rear spring by jacking the body up. Right now everything is working against you, including the brake springs, emergency brakes, and anti-rattlers so if you're fighting it, pull those clevis pins.

[Russell Reay]

Originally Posted by GRutter

If not done already, take the weight off of the rear spring by jacking the body up. Right now everything is working against you, including the brake springs, emergency brakes, and anti-rattlers so if you're fighting it, pull those clevis pins.

I am down to bare bones--see photo, minus the wheels. I agree w/ nkaminar that measurements should locate the problem. but nothing has changed since initial disassembly. Housing didn't fall over, RR didn't either, used same gasket thickness when re-attaching housing. Logic tells me I need a microscopic bend in the torque tube, but w/o a bulldozer parked nearby as an anchor, it's hard to assemble a lever and fulcrum.

[Big hammer]

A rachet strap from the axle to the bumper and pull it back, or hold on to the frame cross member and push the axle with your legs, or chalk the front tires from behind the tires and roll the rear tires backwards. Help from a strong young person would help!

[Will N]

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Originally Posted by Big hammer

A rachet strap from the axle to the bumper and pull it back, or hold on to the frame cross member and push the axle with your legs, or chalk the front tires from behind the tires and roll the rear tires backwards. Help from a strong young person would help!

Yup, just pull it into alignment. Been there, done that.

[David R.]

I realize it’s different, but yesterday I was reassembling my AA rear axle after complete rebuild and experienced similar problems. What I learned was to leave everything a little loose until totally assembled. I couldn’t get radius rods and spring perches lined up until I loosened torque tube bolts, spring pivot bolts and spring U-bolts. That gained me enough to get everything together and then tighten up.

[chrs1961815]

I literally just went through this yesterday and today. Like already mentioned, things have to be loose until everything is together. A pry bar helps at times.

[Russell Reay]

Thanks for all good suggestions. Will report on techniques used when I finally get it back together.

[mercman from oz]

Radius rod is too long - Russell Reay

[larrys40]

Russell,
I’ve done hundreds of A rear axles. Most of the time the radius rods can be a tight fit if you put your backing plate bolts in first .
My suggestion would be to remove the two forward upper and lower radius to housing and backing plate bolts on both sides unless you are inke having trouble with the one side. Install the forward bolt and nut at the u joint end. Leave loose. Go back to you trouble side and use a decent size line up punch and try to pull one of the leaves in the the housing holes forcing it in and when the other hole lines up tap in the respective backing plate and radius bolt.
You should be able to do this with both e brake and service plates on. Once the one bolt is lined up the other is fairly easy. You will have to tap it in as well but it should pretty much be lined up . Install castle nut and cutter key in when tight.

I do the rear and first most of the time as otherwise you are lining yourself up for a potential fight.
Not a big deal. It may seam logical to do the rear first and then the front but now you have learned why not to do it that way. Yes there are other contortions you can do to accomplish it but they too can be frustrating.
All the best
Larry Shepard

[jerrytocci]

If the radius is off on one side , I would think the same on the other but the other way

[31Tudor]

Originally Posted by larrys40

Russell,
I’ve done hundreds of A rear axles. Most of the time the radius rods can be a tight fit if you put your backing plate bolts in first .
My suggestion would be to remove the two forward upper and lower radius to housing and backing plate bolts on both sides unless you are inke having trouble with the one side. Install the forward bolt and nut at the u joint end. Leave loose. Go back to you trouble side and use a decent size line up punch and try to pull one of the leaves in the the housing holes forcing it in and when the other hole lines up tap in the respective backing plate and radius bolt.
You should be able to do this with both e brake and service plates on. Once the one bolt is lined up the other is fairly easy. You will have to tap it in as well but it should pretty much be lined up . Install castle nut and cutter key in when tight.

I do the rear and first most of the time as otherwise you are lining yourself up for a potential fight.
Not a big deal. It may seam logical to do the rear first and then the front but now you have learned why not to do it that way. Yes there are other contortions you can do to accomplish it but they too can be frustrating.
All the best
Larry Shepard

I do the process exactly as Larry has described!

[Dennis Pereira]

I just went though this today do the front first and leave loose then the rear follow Larry's instructions . I wish I read these post beforehand would have saved a lot of time lol .

[larrys40]

Wish you had as well but That’s ok , we all learn from each other. Glad it helps. This is the reason and purpose of the forum .
All the best guys !
Larry

[SeaSlugs]

Originally Posted by David R.

I realize it’s different, but yesterday I was reassembling my AA rear axle after complete rebuild and experienced similar problems. What I learned was to leave everything a little loose until totally assembled. I couldn’t get radius rods and spring perches lined up until I loosened torque tube bolts, spring pivot bolts and spring U-bolts. That gained me enough to get everything together and then tighten up.

yea the AA rearends are fun lol - no forgiving on them. I think i slipped the bolt in the torque tube connection left loose then bolted to the backing plate/tube ears.

[Russell Reay]

Ten points and a gold star to Larry and Dennis for recommending that the front end of the rods be attached first. I left everything loose, and found that with the front bolt in and the nut just attached by several threads, the rear bolts into the backing plates fell right into place. No need for pry bars, come-alongs, or creative body contortions. The logic escapes me, but it worked.

[SeaSlugs]

Originally Posted by Russell Reay

Ten points and a gold star to Larry and Dennis for recommending that the front end of the rods be attached first. I left everything loose, and found that with the front bolt in and the nut just attached by several threads, the rear bolts into the backing plates fell right into place. No need for pry bars, come-alongs, or creative body contortions. The logic escapes me, but it worked.

always glad to hear! thanks for coming back to tell us what worked :P

yea i dont understand the physics behind it either haha.