Model 70 custom

[John DeBree]

I wasn't sure where to put this, so move if necessary. This is my Model 70 project. I don't know what to call it- Hi
Crop? Super 70? Anyhow, I started this 25 years ago (!) but life got in the way as it so often does. Now retired, I'm back at it. This started out as a junkyard Model 70, with parts borrowed and begged from all over. I got the bright (?) idea to put Farmall Cub wheels and tires on it. I made adapters for the rear, and a custom front axle assembly to handle the new height and bigger Farmal front wheels. I used trailer hubs to bolt the fronts on to. So far, it's just a roller. I have a couple K161's to choose from to make it move under its own steam. I have a creeper drive, which may be necessary, as the 38" tall rear tires work out to 11.4 MPH in 3rd gear. The fenders are from a Farmall Cub, too. I made a bracket to mount them. Ground clearance is 16" under the front axle, 14" under the rear, so it would actually be pretty good for cultivating.

 

[danderson]

 

[mfrade]

That's cool , I like it.

 

[lbuttke]

Heres one I did a few years back, found it mighty tippy on uneven surfaces.

 

[John DeBree]

I've thought about it being tippy. I'm just building it as a show piece, although I will see how it does in the dirt... carefully! It's pretty wide, though.

 

[kashaver]

dishing the wheels out and the spacers should help a lot.

That reminds me of the Farmall Cub I bought once. The seller said his dad bought it and 'didn't like it much'. After I got it home I found obvious roll-over damage. If I tipped over a tractor I 'wouldn't like it much' either.
It was also about as narrow as you can make a regular Farmall Cub. And it had a turf tire on the left with an AG tire on the right, so it was already tipped to the left even on level ground. I put AG tires on both sides and moved the wheels so its about 4" wider and it hasn't even scared me yet.

 

[Rbertalotto]

Would filling the tires lower center of gravity and make it less tippy?

 

[lbuttke]

Would filling the tires lower center of gravity and make it less tippy?

Dont think that would help lower center of gravity, but would put more strain on motor to get tractor moving and wear out breaks quicker due to added weight to stop.

 

[John DeBree]

It's 8" taller, but 16" wider, so in theory it should be plenty stable. The custom-made front end is wider, too. I have a set of Farmall Cub rear wheel weights at 150 lbs. each I could put on it. It would lower the center of gravity slightly, off-setting some of the weight above the center line of the axle.

The added width, tire size, and weight is going to be harder on everything from the steering to the drive train to the rear axle bearings. This is a toy that I'll bring to a few tractor shows and putt around our property with. I think really working it would damage some components pretty quickly. I have stock CC's for working.

 

[lbuttke]

As a yard runner / show piece it should be little to worry about, but as you say, as a work tractor it would be hard on the drivetrain.
However, homebuilt equipment to hook behind it would look at shows.

 

[lbuttke]

If you could find the hi/low gearbox it should improve the longevity of the tractor.

 

[thoffman]

Cool! I like it.

 

[John DeBree]

As I mentioned in my first post, I do have a creeper (hi/low) drive. That reduces it 4:1. It also increases the torque by the same amount, so I would think there would more chance for damaging the rear end. Those rear ends are the same ones they put in the Farmall Cub, though, so they are pretty stout. Couple that with the little 7 hp motor, and I think it will be OK unless I really try to strain it. If I were pulling hard, I would think the front end would come up pretty easy, so I'll have to be careful in that regard.

 

[kmcconaughey]

It sure does look nice! I think a K161 might be a bit under powered for it with the larger tires though.

 

[lbuttke]

My thinking is the hi/lo would actually be easier on the motor and trans at the gear reduction it provides, only the added weight of the wheels and tires would be a worry.

 

[kmcconaughey]

This nicely done mini 560 that John Proeschel built, based on a model 70 (I think it's was a 70, has a K161 in it anyway...) seem to struggle to move itself. Though it was able to pull a plow at Blunier's first Plow Day back in 2001. It might have had some other issues that caused it to seem under powered, but at the time I saw it I assumed it was due to the larger rear tires.

 

[tlavalette]

Ever think of stretching it it?

 

[John DeBree]

Nah- I'll leave the frame stock in case Model 70's are worth enough to retire on some day. Everything I've changed is bolt-on, since I don't like carving up factory stuff, even if it was a derelict.

 

[lbuttke]

Had no problem pulling a 10 inch with a 10hp and hydro with tall tires.

 

[eleedom]

Would filling the tires lower center of gravity and make it less tippy?

As long as it is the lower half of the tires, it would lower the center of gravity, however strain on a 7 hp engine moving 500 or so pounds would not exactly make it snappy!