Small Frame Tranny Rebuild...

[Mike_H 92]

Well, Maybe anyway. I need some more expert opinions from you all on here. The plan was to rebuild the 5010 transmission I picked up, and bolt it into my 65 287 Broadmoor. Here is where we started...well not quite, as I've already cleaned up most of the gunk built up over the years.

First the good, I got it cleaned up and torn down. The gears all look really good, and all the bearings roll smooth and look good.

The bad...The seals are all shot -> No biggie, Motion Industries will have them.Input shaft keyway has been sheared...It was brazed, and a new keyway was cut into it. That keyway is starting to go.

Shifter Pawls...one of them looks perfect...The other has some wear. I cleaned it up best I could. Pretty sure this will last another 40 years...

Now, it gets ugly. The spacers look like they may not have been put in the correct places when the input shaft was replaced. Lots of galling on a couple of the bearing surfaces.

Not sure how tight these clearances run in the axial direction on these gears...I can clean up the galling, and purchase (or make) new spacers. I can even shim them if necessary. I have all the die sets and what not at work to make shims. Just wondering if I need to do that, and If so, would I use plasti-gage or something to figure out shim thickness? Or should I just clean the galling up, throw it back together, and let it run? My engineer gut tells me NO...but...I've been wrong before.Thanks in advanced!

[720nut 4,225]

I personaly would clean up the surfaces and make new washers and shims. You've went this far why skimp?

[Mike_H 92]

Spent some after hours time at the shop tonight, and got the galling cleaned up on the parts I'm keeping. The gearcase cover was tricky...Everything else was a 5 minute job in the lathe. Here are some pics...Its not perfect, but good enough for what its doing. BTW, Cast Iron is kind of a PITA to machine.Here is the set up. This took FOREVER to get anywhere close to true to the bed. That is all it is too...close, probably within a few thousandths of true. I set it up on three points, and jacked them around until an indicator read within a couple thou end to end, and a couple thou front to back.

As is normal with this kind of stuff, 45 minutes of set-up and 15 minutes of machining. Left me with this!

There was one groove that was just too deep. I could have gotten it out, but I figured that with the new spacers going in, the ribbon of missing material wasn't going to hurt anything. Next step is to make a couple new "special" washers, and figure out the input shaft. Once I get those in, the tranny will get put back together with lead solder in every area I removed material. I will fully assemble the tranny, torque the bolts, then tear it all back down. The lead will have squished into the gaps that I created by machining the galling out, and I will make some shims to fill that gap, minus 0.010." The 0.010" number came from me assembling the very best washer I had to the area in the housing that did not have any galling. The solder trick yielded a 0.010" clearance total. So, in assembly, there should be a 0.005" per side running axial clearance. At least that is the theory. If I blow it up...Broadmoors are Cheap!

[720nut 4,225]

Lookin gooddOd

[CooterDavenport 0]

sounds like a good theory to me

[fishnwiz 3,290]

These things make my head spin!

Nice work ....it's nice having the right tools ( Or access to them) for the job at hand which is something I never seem to have.

[Mike_H 92]

quote:Originally posted by fishnwiz

These things make my head spin!Nice work ....it's nice having the right tools ( Or access to them) for the job at hand which is something I never seem to have.

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id="quote">Having access is key. Plus my dad is a toolmaker turned business owner so I've been around this stuff for as long as I remember. Now my career is engineer/managment, and the tool room just happens to be something within my management responsibilities. I need to keep "current" and make sure I know what I'm talking about when I have my guys do something :thumb: At least that's my excuse when anyone asks me about my government work!