Ford model-T tractor converson

[jdcrawler]

The model-T has a driveshaft housing with the driveshaft rotating around inside it.
At the rear axle, there is a large roller bearing that fits inside a bearing housing and rides on a case hardened sleeve that fits onto the driveshaft.
There is a thrust bearing in front of this roller bearing.
The pinion gear fits onto the end and is held on with a nut.
The driveshaft is pinned into the U-joint on the back of the transmission to hold it up against the thrust bearing.




While putting this cut off section of the drive shaft together, I realized that there is nothing to hold it up against the thrust bearing. When the tractor isn't running, this input shaft can move in and out and it is only pushed up against the thrust bearing by the force of the ring and pinion gears meshing together at the angle.

The model-T relies on the long driveshaft being held in the U-joint on one end and the roller bearing on the other to keep it from wobbling.
With the short input shaft being held only by the roller bearing, there is enough slop so the shaft can wobble around a little along with being able to move in and out.

So I have decided to re-engineer this input shaft assembly.
1960 Chevy front inner wheel bearings are just the right size to fit snugly over the hardened sleeve.




The outer race on these bearings are a little smaller than the bore in the model-T bearing housing.




I made up a sleeve out of a piece of pipe that is pressed down into the bearing housing.




It is then welded thru two holes in the housing to make sure that it never moves.






Then I put it on the lathe and start machining the counterbores for the Chevy outer bearing races.





The Chevy wheel bearings now fit into each end of the housing.




The thrust washer is removed from the input shaft and a piece of steel tube is put on there in it's place.




The input shaft in now supported by two tapered roller bearings.

 

[jdcrawler]

The two holes in the driveshaft yoke are welded back up and smoothed down.




The input shaft is cut to length and pressed into the yoke.




Then the yoke is welded to the input shaft.




I have left the input shaft long enough to leave room for a spacer washer to go on it. This way, if I need to adjust the length later, I can change the thickness and location of the spacer washer.




These are the parts for the old oil seal.
There is a felt seal with a steel washer that is slightly concave to force the center of the felt tighter around the shaft.
This is all held in place by a brass cup that fits snugly over the end of the housing.




As you can see from this photo of the rear axle when I was cleaning it, this oil seal didn't work very well because the underside of the axle was coated with gear lube.
a lot of the leakage would have been caused by the input shaft being able to wobble a little and move in and out.




Looking thru my box of oil seals, I found a pair of matching seals that fit nicely on the end of the yoke.
One is on the yoke and the other is sitting on top of the housing. They are a little larger than the opening in the housing so I'll have to machine that for them to fit.




The hole in the housing is opened up and the two seals are installed. I know that one seal will probably be enough but I have room for two so why not put them both in ?




The bearings will be lubricated by the gear oil in the rear axle but I went ahead and greased them before I assembled everything anyway.
The mounting flanges of the two housings have RTV sealant spread on them.
The nut is tightened down on the pinion gear and has a cotter pin installed.





The new input shaft assembly is mounted back onto the rear axle.

 

[MNGB]

That's some good modifcations JD and just looking no one would know unless their very familiar with a Model T differential, have a question I see the axle housings have been cut off to narrow it up so was it originally riveted like that or was that how it was done vs welding

 

[jdcrawler]

That's some good modifcations JD and just looking no one would know unless their very familiar with a Model T differential, have a question I see the axle housings have been cut off to narrow it up so was it originally riveted like that or was that how it was done vs welding

The axle housings were originally pressed into the center housing and then riveted to make sure they didn't loosen up.

 

[steve b]

I have one of those roller bearings I dug up in the garden. I never knew what it was. Thanks for the answer!

 

[jdcrawler]

The driveshaft is assembled and bolted onto the back of the transmission.




The rear axle is setup on blocks on the die cart.
The cart is pulled up to the back of the frame with a ratchet strap and the axle is lined up to the driveshaft.




I clamped bars to the side of the sprockets on the rear hubs and quickly discovered that the two alignment bars were wider than the sprockets on the axle by about 1/8 inch on each side.
I had measured the width of the rear hub sprockets when I assembled the rear end to make sure that they were the same width as the sprockets on the axle so I'm a little confused as to why everything isn't lining up correctly.




Come to find out that the two rear hubs are out of parallel just a little bit. It doesn't hardly show up when measuring across the front and back of the hubs but when I measure across to the lugs on the tires, the front measurement is about 3/8 inch narrower than the rear measurement.

You can't see the difference in the tires, front to back and the sprockets being off 1/8 inch at about a foot out from the center of the hubs isn't going to effect the chain drive at all.




The axle mounting bracket on the right side is leveled to the frame and the axle is set so there is a good 1/4 inch clearance between the driveshaft U-joint and the frame.
I'm ready to start making the two pieces that will extend the frame out the rear for the axle to bolt onto.




With the mounting bracket on the right side level, the mounting bracket on the left side is out of level by about 1/4 inch front to back.




The mounting brackets are welded to the axle housing with this one weld so it will be easy to cut thru that so the bracket can be rotated to level it out.
However, I wont do that until the frame section is welded in place on the other side and the axle is bolted securely to it.

 

[jdcrawler]

I'm using 3-inch steel channel to make the rear frame extensions.
The surface of the mounting brackets on the model-T rear axle is a little higher than the top surface of the back of the frame so I cut a notch out of the channel so the top part of it goes up over the back of the frame.




The holes for the bolts for the mounting brackets are drilled and tapped into the channel.




Threaded tabs are added to the underside of the channel so there is twice the thickness for the threads.




I'm marking a strip of 1/4x1/2 inch steel to fit into the gap on the inside of the channel that goes up over the frame.




This gets welded on the inside across the front end and down the side.




Here is the finished frame extension for the right side.







Then I did the same thing for the other side.
There will be a frame piece going across the back but that won't be added until I'm ready to figure out how the rear PTO pulley assembly will be mounted.




There will be a support bar going from the back of the frame extension down to the hub mount but I haven't decided if I want to make it out of angle iron or round tube.




This gives you an idea of how it will look with the chain guard on.

 

[UncleWillie]

Things are looking good.

 

[KennyP]

Won't be long and you'll be driving it.

 

[jdcrawler]

I started out referring to this tractor as a model-T tractor conversion because of the model-T frame and rear axle on it.
With the model-A engine being the most recognizable part on it, I think I need to start calling it a model-A tractor conversion.

Keeping in mind what it originally looked like .....




Even though I've changed the front and rear wheels and moved the rear axle so it is behind the rear cross frame, I think people will still be able to easily tell that it is the same tractor as in the first photo.




The front axle is only changed a little so they shouldn't have any trouble recognizing it as the same front axle.




Originally, I had intended to scrap the hood and the front hood support because they are just plane ugly. My intention was to use a model-T radiator and a model-T hood to make the tractor look better.

I got to thinking more about that and realized that the model-T radiator and hood would change the looks of the tractor so much that most people would probably not believe it is the same tractor as in the first photo.
In order to keep the overall looks of the original tractor, I'm going to have to keep that ugly hood and front support ( yuck ).

To start with, I now need a different radiator. I have a few old radiators and I found one that will be perfect.
It is an old Jeep radiator.




I took my powered wire brush to it to clean off what rust that I could, then I sprayed it down with the rust inhibitor.




The front hood support bracket is actually the U-shape radiator mounting bracket off and old car that is mounted upside down on the tractor.




As you can see, the Jeep radiator fits nicely inside the bracket.




After the rust inhibitor has dried on the radiator, it is painted.

 

[KennyP]

I'd build it to where it pleases me, not the audience.

 

[jdcrawler]

I'd build it to where it pleases me, not the audience.

That's just the thing. I won't be happy with it if people think I'm trying to pass the restored tractor off as the one in the old photo when it's obvious that the shape of it doesn't look anything like the one in the photo.
I have always been very careful with the spectators and not to try to pass anything off for something it isn't.

 

[KennyP]

That's just the thing. I won't be happy with it if people think I'm trying to pass the restored tractor off as the one in the old photo when it's obvious that the shape of it doesn't look anything like the one in the photo.
I have always been very careful with the spectators and not to try to pass anything off for something it isn't.

I'd just say this is what I envisioned it would look like!

 

[jdcrawler]

That A-frame hoist that I built really comes in handy as a third hand for helping me hold things.
I'm using it here to hold the radiator so I can make the measurements for the mounting bracket.




Checking to make sure the mounting bracket is level.




The piece I'm using for the mounting bracket is part of the original frame. The two ends were bolted to the rear cross frame and it extended out behind the seat.




Two holes are drilled into it for mounting the radiator. The radiator is fastened to the bracket with springs on the studs to allow for vibration. The nuts will get cotter pins in them so they don't come loose.




I'm checking again to make sure that the radiator is level before I weld the mounting bracket to the frame.




The mounting bracket is welded to the frame.




And the radiator is fastened in place.

 

[hamman]

This project is coming along nicely Ray. Thanks.

 

[UncleWillie]

As always, it looks incredible.

 

[jdcrawler]

I'm starting to fit the front support bracket for the hood and as you can see, the radiator cap isn't going to be able to stay where it is.




So off it comes. ...




and a piece of sheet brass is soldered in place to seal up the hole.




The support bracket has been sand blasted and treated with the rust inhibitor. Then the top inside corners are trimmed out to fit around the
radiator.




The front hood support bracket is fastened in place.






You can see here how the cut out areas fit around the top corners of the radiator.




The lower ends of the hood support bracket are bolted to the lower radiator mount with two bolts on the side and one on the back.
This makes the bracket very firm.




The upper mount on the radiator is fastened to the back of the support bracket with a piece of rubber hose in between the bracket and the head of the bolt to allow the radiator to flex.




I have to say that this came out looking better than I thought it would.

 

[jdcrawler]

The gas tank is hanging from the hoist and being lined up for making the mounting brackets.




With the engine sitting a little off center to the right, the tank needs to sit off center also to line up correctly with the radiator.
I'm using 1-1/4 inch angle iron to make the mounting bracket and it lines up nicely for the angle iron to just bolt onto the outside of the frame on this side.






The mounting bracket on the other side is has to sit on top of the frame.
This has a 3/8 inch thick tab welded to it and then the tab is bolted to the outside of the frame.




The gas tank is now mounted in place.








The hood needs to be 32 inches long.
I have part of the hood that came with the gas tank that is 21 inch long and I have the original hood off the tractor that is 28 inch long.

I don't have a piece of sheet steel big enough to form a complete hood so I'm going to have to make it out of these two pieces.

 

[UncleWillie]

It's looking like a tractor again.

 

[MNGB]

Yes it is looking like a tractor and its looking good