Sheared axle key?

29ModelA

29ModelA

Well-known member
I was driving down the road this morning to a car show with my son. We went to leave a light and then we had 'no go'. The engine was running great, It was going through the gears when shifting, the speedometer was even acting like we were moving, but the car will not move.

My other thought was a u-joint but if it was the u-joint that was the easiest and quietest u-joint failure in the world.

So onto a flatbed we went and I missed the show.

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How do I check the keys? Are they a hard repair?

My repair manual is with the car at my fathers house until I can pick it up later tonight or tomorrow.
 
Once you get the wheels and axle nuts off you may be able to see if the keyways are not lined up. If you can't see that, then the drums have to come. And, of course, the first drum with have a good key.
If it was the u-joint that failed, the speedo may/probably would not work.
 
My first thought is that you broke one of the rear axles right at the inboard end of the key slot. This is where they generally break. Whenever I rebuild a rear axle assembly I inspect this area on both axles very carefully. Quite often I find a crack beginning right at the end of the key slot. Regardless if the crack is short, or progressing some distance, I replace the axle as it will surely break down the road somewhere. Axle cracks are usually caused by not maintain a nominal 100 pounds torque on the axle nuts and the brake drum is then slamming against the key

If your speedometer was turning it means the drive shaft was rotating.

Another possibility is you cleaned off a few teeth off the pinion gear. This can happen when going at a good speed over a rutted road, rail road tracks, or speed bumps.

This phenomenon happened to a friends 1928 coupe back around 1952. As teenagers we were racing down the road at about 45 mph when we crossed over some very rough railroad tracks. My friend kept his foot on the gas. The rough tracks easily caused the rear wheels to be momentarily bounced off the road several times by the rear spring. When the wheels leave the ground the wheels will spin up to a speed much higher than what the car is traveling. Each time they re-contacted with the road there is a tremendous impact placed on the pinion gear. We managed to clean off most of the teeth on the pinion gear.

To this day when ever I cross over railroad tracks or speed bumps in a Model A I take my foot off the gas.

Tom Endy
 
Whenever I've sheared an axle key, it has sounded like a gun went off in the transmission. Don't know whether an axle shears quietly or not. Should be possible to tell which by seeing if the end of the axle turns with car on jacks.
 
If u broke an axle your wheel can be removed without taking the axle nut off. Might try to jack the car up and yank on the wheels for a quick diagnosis. Tk
 
The GOOD news is, if it's just the key, you WON'T need a puller to get the drum off!
EVERY Ford owner up to 1948 year model, should carry a spare axle key, a 15" Crescent wrench, & a pair of side cutters! It's a quick & easy repair. Bill W.
(Once, with NO spare key, I found a large rusty nail by the roadside, drove it in, clipped off the head, tightened 'er up & GENTLY drove home for supper!)
 
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BILL WILLIAMSON said:
The GOOD news is, if it's just the key, you WON'T need a puller to get the drum off!
EVERY Ford owner up to 1948 year model, should carry a spare axle key, a 15" Crescent wrench, & a pair of side cutters! It's a quick & easy repair. Bill W.
Click to expand...

Had I known this was a possibility I would have for the $2 they cost. Really bummed me out not to be able to take it to the Bricks, bummed my boy out too. But considering I have put about 500 miles on it since it's first time out in 40 years, and all that I have had major issues with is this and a timing gear, I'm still ahead.

We went back in with the truck, but he wasn't near as excited.

I do have something loose in the front end now too, so the steering will all have to be re-done this winter.
 
I have to agree with Tom... that it very probably that you could have broken an axle or at minimum a key.... if it's the axle, the wheel can certainly come off.. and should be visible as it will definitely wobble. Pull the hubs and drums and see what's going on. I have seen axles break further in from the keyway as well. Like Tom, I have rebuilt tons ( literally) of rear axles.... and have pretty much seen many a failure. Not too long back I disassemble one that didn't even have a key in the pinion.... If you had a broken pinion tooth the rear would want to "catch" when things are rotated.
I'm confident that upon disassembly of the hubs/axle areas you will find the trouble. The keys must fit tight in the keyways and hubs. If not, the associated parts must be replaced. I torque hubs/drums to 150 ft lbs.
Let us know what the culprit was.
Thx,
Larry Shepard
 
If it is a sheared axle key you should be able to feel it in the wheel---have someone put thecar in gear and another person feel each rear wheel ---the one making some noise and vibrating some is probably where the problem is. ---usually the right rear
 
there is certainly a gold mine of info on this site and I say that sincerely. Here is my puzzlement though, and maybe it is answered above: if a Model "A" axle shaft breaks, doesn't the wheel come off, a highly-dangerous situation?
 
BILL WILLIAMSON said:
The GOOD news is, if it's just the key, you WON'T need a puller to get the drum off!
EVERY Ford owner up to 1948 year model, should carry a spare axle key, a 15" Crescent wrench, & a pair of side cutters! It's a quick & easy repair. Bill W.
(Once, with NO spare key, I found a large rusty nail by the roadside, drove it in, clipped off the head, tightened 'er up & GENTLY drove home for supper!)
Click to expand...

Fits my recollections as a crazy teenaged kid. I recall just buying a stick of key stock at the hardware store and just cutting off a piece whenever needed, spending a few minutes with a file to taper the ends, and being back on the road in no time at all. The more you drove it, the more you knew what tools and parts you need to keep her running. ...and in the sixties that is what I had to drive everywhere.
 
Tom Endy said:
My first thought is that you broke one of the rear axles right at the inboard end of the key slot. This is where they generally break. Whenever I rebuild a rear axle assembly I inspect this area on both axles very carefully. Quite often I find a crack beginning right at the end of the key slot. Regardless if the crack is short, or progressing some distance, I replace the axle as it will surely break down the road somewhere. Axle cracks are usually caused by not maintain a nominal 100 pounds torque on the axle nuts and the brake drum is then slamming against the key

If your speedometer was turning it means the drive shaft was rotating.

Another possibility is you cleaned off a few teeth off the pinion gear. This can happen when going at a good speed over a rutted road, rail road tracks, or speed bumps.

This phenomenon happened to a friends 1928 coupe back around 1952. As teenagers we were racing down the road at about 45 mph when we crossed over some very rough railroad tracks. My friend kept his foot on the gas. The rough tracks easily caused the rear wheels to be momentarily bounced off the road several times by the rear spring. When the wheels leave the ground the wheels will spin up to a speed much higher than what the car is traveling. Each time they re-contacted with the road there is a tremendous impact placed on the pinion gear. We managed to clean off most of the teeth on the pinion gear.

To this day when ever I cross over railroad tracks or speed bumps in a Model A I take my foot off the gas.

Tom Endy
Click to expand...

I was REALLY hoping this is not what happened, but it was. :( It couldn't have been the $2 fix... Jacked up the car, the wheel was loose, grabbed it and it fell off with a slight tug

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ouch::: that there sucks
looks like you got your work cut out for you. while your at it switch the e-brake pins around so the cotters face out
 

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