Early ford trans case: Rear thrust face. Repairable?
 

I have a 41 transmission, matching numbers for my pickup. The rear thrust face has been scored quite badly. Has anyone successfully repaired and resurfaced one of these? I have a lathe and small milling machine but am struggling to imagine how to go about even trying to repair it.

Mart.

Re: Early ford trans case: Rear thrust face. Repairable?
 

These are probably things you have already discounted, being the master craftsman that you are Mart, but
Could you fill in the scored areas with a weld bead and then polish out, or could you cut out the bad section and weld in a new one from another transmission.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Welding castiron and getting it machineable is always tricky...we used to sprayweld heads and that gives a good colourmatch and surface that can be milled.
But that really takes an oven and any surface needs to be covered up to avoid splatter.
Machine it flat and ad a shim since you have a mill.
Drillbushing in each end and a boringbar with a cutter powered by the mill.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Had a customer at my old job, show me an Austin-Western gearbox case that he had a local machine do pretty much what flatheadmurre describes above.

I was impressed many times by the skills of the old-timers in small town blacksmith shops.

Re: Early ford trans case: Rear thrust face. Repairable?
 

What thrust face Mart ?? do you mean were the cluster shaft goes through .Ted

Re: Early ford trans case: Rear thrust face. Repairable?
 

Yes, Ted, the face the rear of the cluster shaft thrusts against. Mine chewed up the thrust washer and has worn the casing quite badly. I think I might have to make a specific tool I was wondering if anyone has already done the same job.

The fact that it is deep inside the trans casing makes it a bit difficult to access.

Mart.

Re: Early ford trans case: Rear thrust face. Repairable?
 

I once took old cluster gear--not on a Ford---ground a groove to hold cutter bit, advance cutter with feeler gauge at other end, kept adding .001, make a revolution, clean shavings, add another .001

Re: Early ford trans case: Rear thrust face. Repairable?
 

Mart, without knowing what diameter tool and arbor you would need you might check into "reverse counterbores", they are sharpened for CCW rotation.These are typically used on a radial drill press or a counter-bore table. Hopefully there is a size that suits your application.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Fire a PM to Mac VP on this and see what he would suggest. I'm sure he has crossed this bridge before.

Re: Early ford trans case: Rear thrust face. Repairable?
 

We worked with a machinist some years ago on this issue. He cut out the damaged rear thrust piece.....completely through the case. He machined a slug of steel in the same diameter of the whole that was cut into the case. The slug had the 3/4” bore drilled into its center and the oil groove to the inside. The slug was placed into the back of the case and then positioned so the inside face was placed at the same location as the original face. The slug was set into place with red locktite and three pins locking the outside diameter of the slug. When positioned correctly, the front to rear inside dimension was the same as a new case. I had perhaps 3 or 4 of these done. I’ve never heard back from any of those customers that they had any issues with the repair.

The downside to this......it cost me about $100 per case to have him do these. I could buy core cases for less back then so it wasn’t cost effective. On top of that, he told me that he didn’t want to do the work anymore.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Thanks for the insight Mac. That's far beyond my capabilities. I do have one more case from my dwindling supplies that I can build the gears into. I'll probably put this case on the shelf so the machining job does not hold up getting the vehicle back on the road.

Thanks for the help, all, I'll get to this one day and let you know what route I took.

Mart.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Mart, I asked Mac this same question some time ago and got the same answer, so when I had two cases that were wasted on the faces as you have, I just found a good case and rebuilt it. By the way those two cases went to the scrap man three days ago. Did I cringe at scrapping them? You bet I did,,,,,,but. :eek:

Re: Early ford trans case: Rear thrust face. Repairable?
 

I think with a long milling cutter you could reach down and machine it ,its setting it up square would take some time Ted

Re: Early ford trans case: Rear thrust face. Repairable?
 

I have used thin hardened steel thrust washers against rough cast surfaces as such and then add an original thrust surface in a trans and it held up. Pictures might help.

Re: Early ford trans case: Rear thrust face. Repairable?
 

I'm not a machinist by any stretch of the imagination, but I have a hard time believing there is not some type of cost effective way to machine that inner surface and then make a shim washer the same thickness of the material that was removed.
Even if it can't be done inexpensively, if someone wants to retain the original transmission case, with the serial number that matches the frame, it may be worth the cost to them..

Re: Early ford trans case: Rear thrust face. Repairable?
 

I made a fixture to fit in my milling machine to go thru the front hole and then attached a boring cutter to reface the surface and added shims to make up the difference. It can be done, just takes some thought and patience.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Always hate to see any original parts discarded...IF there might be a method to save.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Mart,
To satisfy a cost is no object customer maybe 10 years ago I fabbed an arbor
that piloted thru both the front and rear cluster shaft bores. Using a large dia spot facer with a .750 bore attached to the arbor I was able to clean up the disastrous
rear face on a # match case. Now don't chuckle too much but to 'replace' the metal
machined off I made a proper thickness steel spacer with a small knob protruding
on one face. This knob registered into the cast in oil pocket to intentionally keep the spacer from rotating. The final step was an application of DEV CON epoxy between the case and spacer......It works........the trans in my truck has this repair as well with no issues in a few billion revs. The oil grooves in the rear thrust washer were deepened
and a groove added just to be sure. The copper/babbitt bearing material on the washer is happier running against smooth steel than iron in my estimation.
Not cheap.
Charlie ny

Re: Early ford trans case: Rear thrust face. Repairable?
 

angledrive and charlie got the right idea, you can do it mart

Re: Early ford trans case: Rear thrust face. Repairable?
 

some more late night thoughts about hillbilly machine work... i would turn an arbor on the lathe, i know you have one, that fits the bore in the case, then turn one one end down and thread it to the size of a valve grinding stone, and use the back side of the stone to cut, and make a brass bushing to get back to the case size on the stone end. drive it with a drill. you are just trying to make it square with the case, and then shim back to the desired endplay for the shaft. piece o cake

Re: Early ford trans case: Rear thrust face. Repairable?
 

I fixed one such case by machining it flat in the worn area and fastening a thick steel washer with c-sink screws thru the rear face into the washer. Made a simple face cutter from 3/8 square tool steel and piloted at both ends of the case with a piece of 3/4" water hardening drill rod. Although I did the machining on a good sized vertical mill it could be done in other ways.

Re: Early ford trans case: Rear thrust face. Repairable?
 

I've only crossed this bridge once, and it was back in the 60's. (So, I'm dated.)
At the time, we had a cast iron repair place nearby. I took the case to them, and they applied braze material to the severely worn area. Looking back, I know I could have done this myself.
Anyway, they put on extra material, which needed to be machined down for proper cluster end-clearance. I was VERY lucky to work at a place that had a great machine shop. And, I went to the tool crib and borrowed a back-side spot facer. The cutter was the same diameter as the thrust washer that needed to rest there. And, the shaft was the proper diameter to fit the countershaft hole. So, I simply did a back-side spot face, using my drill press. After reading all the above posts, I can't believe how lucky I was to be able to do what I did. It worked perfect.
And, by the way, I'm still in contact with the person that owns the vehicle with that transmission. It's been 50 years, and that transmission is still working fine.

Re: Early ford trans case: Rear thrust face. Repairable?
 

The job is done.

Thanks for all the helpful suggestions.

I slept on it and read all the helpful comments this morning. I started looking at what I had, thinking some sort of arbor was the way to go.

I found an old "tank cutter". It has a 5/16" square hole through it and is close to 3/4" diameter. I hand ground a lathe tool bit to act as a facing cutter.

https://www.fordbarn.com/forum/attac...3&d=1508176315

I built up the shank with the mig welder.

https://www.fordbarn.com/forum/attac...4&d=1508176315

https://www.fordbarn.com/forum/attac...5&d=1508176315

I turned the shank down and set it up in the 4 jaw to get it as true as I could with the original diameter.

https://www.fordbarn.com/forum/attac...7&d=1508176315

At that point I realised it was probably better to try and do the job in the lathe, as the arbor is now as true as it could ever be having just been turned.

I had to use the little myford lathe to turn up a stub to support the other end of the casing.

https://www.fordbarn.com/forum/attac...6&d=1508176315

I couldn't pull the casing with the tailstock as the taper would probably let go, hence the stub support.

The trans case was set up on the arbor and the tool inserted and set up. I gave it a test spin and all felt well, so I started cutting. I all appeared to be going well so I kept going until the face was fully cleaned up.

But the problem was that the face came out concave. Hardly surprising given the setup.

I came up with a quick and dirty way to beef up the tool bit using one of the lathe quick change toolholders. This one has a V at the bottom so clamped squarely to the arbor.

https://www.fordbarn.com/forum/attac...8&d=1508176315

This seemed a lot better so I continued on until the face was fully cleaned up.

As far as I can tell using a straight edge with a light behind the face is flat. It looks good anyway.

https://www.fordbarn.com/forum/attac...9&d=1508176331

So thanks for the comments it really helped.

If I were planning to do it again I would probably make improvements to the tool. But, for what it took, I was surprised at how well it came out.

Mart.







Mart.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Good going Mart. nice and simple. I too have used stainless shims inn the past to fix a damaged case. I think they came from McMaster Carr or MSC products, can't recall but the machinist at work helped me out. no issues.

Cliff Ramsdell

Re: Early ford trans case: Rear thrust face. Repairable?
 

Nice job!

Re: Early ford trans case: Rear thrust face. Repairable?
 

Mart,
Now I know why the industrial revolution started in Great Britain.
I'm thinking you attached the case to the cross slide to feed it into the tool,
yes ? Your method makes the repair absolutely doable...
Charlie ny

Re: Early ford trans case: Rear thrust face. Repairable?
 

looks good!

Re: Early ford trans case: Rear thrust face. Repairable?
 

Great ...Geez you don't muck around, job done!

Re: Early ford trans case: Rear thrust face. Repairable?
 

Nice job Mart. Thanks for posting the pictures showing how you did the job. You got the wheels turning in my head on how an amateur machinist like me might attempt doing this if it becomes necessary to save an otherwise good transmission case.

Re: Early ford trans case: Rear thrust face. Repairable?
 

SHEEEESH Mart.................Let me see if I can go find that scrap guy and send those cases to you. ;) Fine job. :cool:

Re: Early ford trans case: Rear thrust face. Repairable?
 

Not quite, Charlie. The case was floating between the stub arbor in the 4 jaw chuck and the 3/4" support in the tailstock. I just nudged the toolpost against the casing and gently pushed it to the right allowing the tool to cut the inner face.

I didn't take a photo of the setup but did make a couple of little movie files, I can't post them here, but if I get them up on youtube I'll put a link in here.

Thanks all for the kind words.

Mart.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Bloody genius !!
Charlie ny

Re: Early ford trans case: Rear thrust face. Repairable?
 

You do nice work! Quick too!

Re: Early ford trans case: Rear thrust face. Repairable?
 

Yeah, post those movies on YouTube please :)

Re: Early ford trans case: Rear thrust face. Repairable?
 

Ok, you asked for it..

A bit rough and ready and not edited at all. I'm a very untidy and messy worker.

Part 1 (the first attempt - came out concave due to insuffient tool support).
https://youtu.be/WBRWMXzZXR4

Part 2 (just a quickie. - with the tool backed up by improvising a tool holder clamped to the arbor)
https://youtu.be/uFWaF82F8yU

Mart.

Re: Early ford trans case: Rear thrust face. Repairable?
 

Remarkable ingenuity!!!!!!

Re: Early ford trans case: Rear thrust face. Repairable?
 

love how that turned out.. If I did it I know with 100% certainty that the tool would have grabbed and somehow ejected the case onto my foot lol

good for you for having better execution and all of your toes!

Re: Early ford trans case: Rear thrust face. Repairable?
 

Well done, where there is a will there is a way.

Re: Early ford trans case: Rear thrust face. Repairable?
 

nicely done

Re: Early ford trans case: Rear thrust face. Repairable?
 

I go with Charkie. Making up a spot facer would be quite simple and a steel spacer could be pined and epoxyd to the case. Or a standard mill could have the reverse cutter on it. My onlly concern is how thick is the case in this area. I gave up on these transmissiond 60 years ago after I blew my third or fourth one. However for the restorers I believe these are fixable, at a reasonable price. At my age and eyesight , I think I could still do it. If someone had bad case I'd' TRY and fix it, at no charge. But it has to get alittle warmer, it was 16 below this morning.