I have had great luck with Betsy, my 1924 cut-off touring, and my first Model T Ford. Since I bought Betsy in 2013, I have put almost 4000 miles on her without any significant issues.
This afternoon, about 5 miles out on a drive, I heard a mild "pop" as I started across an intersection. The engine kept running fine, but the car rolled freely, no drive in forward or reverse. Luckily, my AC brakes still worked, so I didn't roll into the middle of the intersection.
Once I got Betsy home (thanks, AAA!), I noticed that the left rear wheel and drum is sticking out about 1/4 inch further than usual (see picture).
My initial suspicion is a broken left axle shaft. Tomorrow, I'll jack up the rear end, relax the outside brake band and see if I can pull the left wheel off along with a stub of the shaft. If it doesn't come out, I'll have to disassemble further to see what the issue is.
The receipts from the shop that restored the car for the previous owner say that the thrust washers were replaced with bronze, we'll see.
I'll remove the left side rear axle housing and pull out the center section and axles for inspection. If all is well except for the one axle, I'll probably replace both axle shafts with new ones and button it back up.
If there are more serious issues, I'll likely pull the whole rear end a slide my rebuilt Ebay Ruckstell under the car. Then I'll have to decide which brakes to install, the current period ACs, or my original design Rocky Mountain brakes.
Wish me luck!
Mark,does it have some sortof safety hubs?When an axle shaft goes,that side of the rear end goes down with a bump.Usually right away.So,with safety hubs,you can have a broken axle,amd it will not pull out.
Good luck, Mark. Hope it goes well.
No safety hubs (that I know of, no mention of them in the receipts). Maybe the shaft is broken further in, like at a groove worn in it from an original spring steel-backed leather inner grease seal? Or maybe further in, at the shaft gear?
Just speculation at this point. Stay tuned!
Here is a picture of the hub area from a few years ago when I installed the AC brakes. Wouldn't it look a lot different with safety hubs?
Yes, Mark. You would have a hub bolted onto the inside of your brake drum that you would have to slip out of the axle housing in order to remove the wheel. You don't have safety hubs. Now is the perfect time to install that Ruckstell you were telling me about.
Don't need to wish you "good luck". You already had it. A potentially disastrous failure in a nice safe place where you became merely a minor annoyance to traffic.
Regardless. Good luck with the repairs!
Thanks. I should also mention that several local folks stopped to make sure I was OK and one person gave me a bottled water in case I got thirsty waiting for the flatbed!
Mini car show even when broke down and waiting. That's actually really nice. :-)
Looking at your last photo I was struck by the combination of standard inside brakes and the outside AC brakes. I've wanted to ask someone with that combination how they were mechanized and how well they worked.
Is one brake a foot operated system and the other operated by the hand brake lever, or do you have it hooked up in some other way ? Do you still have the internal transmission brake ?
Also, can you use both the outer and inner brake at the same time ? Does it heat up the drum excessively due to friction devices on both sides of the drum ?
OK, I couldn't stand the suspense, so I went out to the garage tonight and removed the wheel. It slid right out, along with a 6 inch stub of the axle, when I released the grip of the AC brake band on the drum.
I cleaned things up a bit for the photos, but it's clear that I've been pumping way too much grease into the Hyatt bearing cavity - there was grease coming out of the outer seal and getting all over the backing plate and emergency brake shoes.
The modern aluminum bodied outer grease seal has come apart, I don't know if it was that way for a while due to my excessive grease pumping, or if it got damaged when the axle shaft broke.
The location of the axle shaft break coincides with the inner grease seal for the outer Hyatt bearing. The axle shaft does not appear to have a groove in it like some I have seen where the old metal-backed leather seal has cut into the axle surface.
I've attached several pictures of the outer part of the fracture surface. Some of the surface has rust on it, as if one or more cracks had been there a while.
I'm not an expert at this, but it appears to my eye that the final failure occurred when only about 1/3 of the cross section was left un-cracked.
The bearing sleeve was starting to extrude out of the top of the housing, I have seen this condition before in pictures elsewhere on the forum. I used the extraction tool and can get the sleeve to turn, but it's not wanting to come out yet, it just spins in place.
Enjoy the photos, comments are welcome!
Dick, my AC brakes are period original, so they are cable operated. I purchased the equalizer kit from one of the vendors, connected it to a reproduction Rocky Mountain brake pedal, then use the equalizer to pull on the cable. One disadvantage of this setup is that the AC brakes take over the function of the parking brakes, the factory parking brakes don't get used.
I have fabricated a different equalizer setup that de-couples the parking brake function from the AC brakes so that they both will work independantly - I just haven't installed it yet.
(Message edited by cudaman on May 07, 2017)
Not sure why the link I posted didn't come through as a link, here it is again:
Sorry to hear about your broken axle. I am glad that no one was hurt. The pattern of the break is typical of a crack caused by fatigue. Here is basically what happens:
1. Cyclical stress are applied to a shaft as it turns and causing slight bowing of axle.
2. A defect, almost always on the surface, focuses the stress in one area. (This is the same effect as etching the surface of a piece of glass, but since the steel is less brittle it doesn't break as quickly.) *I believe the rusted color area is the defect where the crack started.
3. The crack propagates as stress continues to be applied. Perhaps each ring is from just a bit more of a load. A bump in the road?
4. After a good deal of the axle is broken the process continues quickly and the shaft totally fails.
Mark, I have used a scissor jack between the axle housing plate and the sleeve removal tool rod to help get the sleeve out. Just go easy on the scissor jack or you'll bend the tool.
I agree with HLLG on the mode of failure, but then, Dick Fisher is the materials expert in our neck of the world so It will be very informative to hear what he thinks.
Another question I have, if the Hyatt clearance is too tight might that also result in the extruded sleeve and fatigue failure of the shaft? Or would a bent tube be a more likely cause? Or... could it be possible that deflection from the A-C brakes might play a role in this mode of failure?
Hello Mark: I had the same problem on my Hack. Took it for a drive and was about 1/4 mile from home, went down the drive way made a right turn went to the next corner , made another right turn and went from low pedal to high pedal and there was a loud bang and the hack came to a stop. My neighbor come down with his jeep and towed it home. Checked for a bad axle and it was broke just out side the center section, and the break was because of flaw in the axle. Have it ready to install in the Hack. Oh what fun it was to tear it down and rebuild and get it ready to go back together.
Welcome to the club.....
I had exactly the same problem. Went to pull away across an intersection, click and no go. We were only 2000+ miles from home on a trip to Western Australia. Because I was running modified rear axle bearings, I carried my own spare machined axle. Our support vehicle picked me up and we fitted the new axle in a T enthusiast's workshop. I was able to repay the help by finding him a turtle deck for his 1915 roadster a couple of years later.
Allan from down under.
This is a question I would like to throw out to the members of the two-piece rear axle club: Was the axle shaft that broke an original Ford, or a modern reproduction?
Mark, sorry to hear about the broken axle. I would definitely use the opportunity to swap in the Ruckstell. Hopefully you rebuilt the Ruckstell with new axles.
I'm curious about the third picture down on your 12:29 AM post, which is looking straight into the axle tube at the remaining end of the axle.
Is that brown ring that I see around the perimeter of the fractured axle part of a seal, or some grease, or is it rust on the axle end itself ?
Chad, unfortunately the Ruckstell has "good" used axles in it. If I had it to do over again, I would have definitely installed brand new axles.
You know how it goes, "it hasn't happened to me yet, so it must be a rare occurrence".
Dick, I haven't removed it yet, but I strongly suspect that the brown ring is the edge of one of those leather inner seals that have the spring steel "fingers" to apply pressure to the leather. I have heard that the "fingers" can wear a groove in the axle shaft, which gives cracks a place to start.
I'm still pondering my options, but as of right now I think I'll install the Ruckstell and continue to use the AC brakes and equalizer setup that I currently have. The plan is subject to change at any time.
I'll post further updates on the teardown in this thread, but post progress on the rebuild (when it starts) in a separate thread.
Thank you everyone for your comments!
Hi Mark it was nice talking to you today at the swap meet. I was sorry to hear about this broken axle shaft. Now that I am home and see the photos I see what you were talking about.
If you want to repair this rear end give me a shout. I probably can come up with a shaft to replace the one that broke.
Mark, I bought a cross shaft set up from Rich Bagman for my large drum Cleveland brakes on my 26 coupe. I thought about using the equalizer setup like you have but, I decided against it because I wanted my hand and foot brakes to remain independent. So far the brakes are working great. The hand brake still locks the wheels for parking and emergency use and the cleveland brakes are used for the majority of stopping. Just another option for you to consider.
Thanks Herb, nice to meet you too.
Since the other side probably has the same kind of leather seal chewing on it, I think I'll buy two brand new shafts when the time comes to rebuild it.
Nothing like having virgin metal with the fatigue counter starting at zero!
It would be a good time to get the Fun Projects pinion bearing. I installed that after a new repop bearing sleeve failed. It is really easy to set up with minimal time involved. http://www.funprojects.com/products/2587e1.aspx
That's in the plan for the rebuild. The Ruckstell already has one, along with the neoprene inner seals instead of the evil leather ones.
Personally Mark, I would buy a set of axles for the rebuilt Ruckstell, put them in and install the unit in your car. I think you would be miles and time ahead.
Makes me glad I decided to do a new set for my rebuild. We also had a member in our club that lives on a VERY steep mountain hill that broke his starting to go up it on the way home from a day out and about. How he didn't have more than minimal damage to the car and his shorts, I'll never know. He got real lucky. He decided on the safety hubs for his build.
Wow Michael, the fracture surface of your axle looks almost exactly like mine! Slow fatigue crack progression for about 1/2 the axle thickness, then more rapid progression until ultimate failure with about 1/3 of the axle thickness left.
I got the stub of the axle out of the wheel today. It has no "Ford" marking, aren't the original axles stamped at the bottom of the keyway slot?
The key is an original stamped "Ford" key. Both key, keyway, and threads are in good condition. A pity!
Trent, To answer your question posted above about axle shafts broken on Model T's, the one I broke was a modern reproduction and it broke right where the taper begins.
I was was seriously considering buying new axles for the rear end I am rebuilding, but if the issue happens with new and old it doesn't yield much reassurance.
Mark, just wondering if you had the felt ring installed between the hub and the outer seal?
Matthew, I know what you're thinking on new vs. original Ford axles. The thing is that new ones aren't worn on the bearing surfaces and on the taper. If you use original axles, be sure to check for wear on those places as originals are often worn. Just a "heads up".
The break in the axles in the photos appear to have been created at the time of manufacture most probably incorrect cooling. Here is a photo of a train rail that was a victim of incorrect cooling, hydrogen was trapped in the steel and was not able to escape. With a modified cooling process this can be eliminated. In the early days there were many train derailments because of broken rails. A metallurgist named Mackie patented the process of cooling to eliminate the hydrogen problem.
Dave, no felt ring.
I got the Hyatt bearing sleeve out. Instead of just applying twisting and pulling on one side with an alignment tool, I found a long piece of rod that could go through the holes and allowed me to pull and twist evenly on both sides. That made all the difference.
The sleeve has a lengthwise crack on its top surface where the vertical loads were concentrated:
In my experience, axle shafts break due to two reasons. First, an axle housing is bent. As a result, the axle shaft does not run true, and the shaft tends to bend a bit when supported by the outer roller bearing. In severe cases, the new axle shaft will have a short life of a few hundred miles before it breaks again.
The second reason is due to using original Ford axle shafts made from AAX vanadium steel. In this second situation, the shaft tends to break between the end of the roller bearing and the point where the taper enters the hub. Original AAX axle shafts are more prone to metal fatigue than are new replacement shafts, properly heat treated.
Well, I removed the inner grease seal and it is indeed the leather one with the spring steel "fingers". I'll post a picture tomorrow, for some reason my tablet won't recognize my digital camera when I plug it in.
I also cleaned up the Hyatt bearing, and one (only one) of the rollers has a slightly pitted surface like it got wet at some point. The cage was also a little loose, but tightened right up with peening of the ends of the cage support rods. I haven't measured the diameter of the rollers yet.
If the axle was installed as a solid unit with no fractures then there would be no rust at the break. The axle appears to have been exposed to oxygen some time in its life therefore I believe the break was not caused by any misalignment or abuse.
As has been mentioned, bent axle housings could be a contributing factor. A couple of weeks ago I made some fixtures for checking housings for straightness. We tested about a dozen housings and found two with significant bends ( at least a inch off center with the fixtures installed). We straightened one using a heating and cooling approach. If the axle shaft is not close to perfectly centered prior to installing the outside bearing, I would be concerned
Luckily, I checked the Ruckstell that will go in for alignment when I built it up, so hopefully no issues there. I'll slowly pick away at this project over the next few weeks, no need to be in a rush. Time to let this thread sink out of sight for a while....
Last update on this thread, before I start a new thread on the Ruckstell installation.
I pulled the standard rear axle out today using my wood jack adapter and a big pickle bucket to support the front of the driveshaft. Tomorrow I'll wheel the standard axle down to the basement using my dolly, and bring up the Ruckstell to get it ready for installation.
Oops, needed to rotate the third picture.
The type inner seals shown in your picture can sometimes cut a groove in the axle shaft. That would be especially possible if the shaft is bent. The crack on your sleeve indicates a lot of pressure on the side which is cracked. Check the alignment of the housing and use a different type seal on your replacement.