140 belt pulley drive

[rusty9930]

So I purchased a '73 140 about a year ago. It came with an IH C-3 60 inch belly mower which I want to use. Took awhile to ID the mower deck but eventually figured it out and even located an owner's manual for it which has helped tremendously. Willing to get that to the forum if someone would tell me how. The tractor itself is in OK shape. Found the distributor installed 180 out, and the expected leaks from the fuel bowl and carb needed rebuilding. Looks like the ballast resistor might be bad again so figure I'd replace the typical pieces at the same time; cap, rotor, points, etc. Writing this here looking for some guidance on building a new "mule drive". The drive belt for the deck as bought ran thru a mule that I think belongs on a Cub. There was a large pulley on the PTO shaft, ( belt pulley drive did not come with the tractor), and the left fender was bent to provide clearance. The belt was crossed to get the blades turning in the right direction but at the PTO output approx 540 rpm it cut but not well. I located and installed the belt pulley drive and the gear to power it and that seems OK as far as I can tell though using hydraulic fluid as the book calls for seems to make a lot of gear noise. It spins in the opposite direction at about twice the speed of the PTO. I wasn't able to locate the 2 pulley mule which goes between the drive and the deck so it looks as like I will need to build one. Luckily the C-3 manual has a b/w photo and a drawing of it which is a great help. If anyone else has built one of these and would like to share their experience that would be great.

[Jim Becker]

. . . I located and installed the belt pulley drive and the gear to power it and that seems OK as far as I can tell though using hydraulic fluid as the book calls for seems to make a lot of gear noise. . . .

When installing the belt pulley attachment, the mesh and backlash of the pair of bevel gears needs to be adjusted. If they are not, they will be noisy and not wear well. There are 2 stacks of adjustment shims in the assembly.

[rusty9930]

Jim, thanks for the note. I ordered with the drive 2 of the metal spacers, ( gasket?). I installed it just using the thicker one. What is the procedure for adjusting them?

[Jim Becker]

IH didn't give much instruction on how to adjust them:

"Assemble the belt pulley assembly in place using sufficient shims to obtain the proper back-lash between the bevel gears. (Back-lash is .004 to .006-inch.)"

There is a plug in the top of the pulley housing. Remove it to see the gears (and I suppose measure the back-lash if you can figure out some way to do it). If you can measure the back-lash, I would err if any towards the larger end of the scale, assuming there is some wear on the gears.

[rusty9930]

Jim
Thanks I'll see if I can fit a feeler gauge down in there. I read the repair manual for the A model with a belt pulley drive. That stated to clean the gears free of oil and then paint the teeth with dykem, ( not sure I spelled that right). Then by turning the gears in one direction only you look to see if the contact is in the center of the teeth, not hitting the edges of the teeth. Sounds possible but certainly not simple or quick. The folks I bought the drive and shims from suggested that I would likely only need a single shim and only add another if there was a loud gear noise - of course loud is undefined. I figure to leave it for now while I work on building a mule. Then I'll need to acquire a belt of the correct length and get it adjusted to wear properly. Then we'll revisit the belt pulley drive gears.

[Jim Becker]

Sounds like you have better instructions than I do. You probably won't get anywhere with feeler gauges. A dial indicator would probably do it. By the way, you can probably measure the back-lash on the pulley. Get the diameter of the driven gear at the middle of the teeth and the diameter of the pulley at a place you can measure rotation. Multiply the .004 to .006 by the ratio of those diameters.

[rusty9930]

Completed the "mule" except for paint. Stretched the old drive belt to help align the pulleys. Now to see if I can get a belt that fits and get some International red on there. Having the pictures in the C3 manual was a great help. Tried a diamond Lennox blade in my angle grinder to cut the steel but found the much cheaper abrasive wheels much easier and quicker to use, not sure what the Lennox is supposed to do?

[Rick Spivey]

Tried a diamond Lennox blade in my angle grinder to cut the steel but found the much cheaper abrasive wheels much easier and quicker to use, not sure what the Lennox is supposed to do?

I use one for remodeling our old farmhouse, in which the "plaster" walls are actually 3/8" backer board with 3/8" cement troweled on top, and then 1/32" of plaster over that. It cuts sections of that out very well. Also useful for cutting the remains of old nails out when the hammer claw won't pull them.

[rusty9930]

Thanks Rick - saw it on the shelf and thought it would cut angle better than an abrasive disc. Very wrong!
Like the TR 6 - miss my TR 4A!

[rusty9930]

I finished up the mule and bought a 140+ inch belt for it. At first the belt was too short but I reconfigured the mule a little to get it running. It stretched out a bit now and seems to work fine. Did some mowing and it cuts very nice , you can certainly see the improvement in blade speed. I calculated the old setup blade tip speed at 75 mph. The new setup runs at 160 mph if I did the math right. The belt travels at 34 mph. Used angle iron and a flat pulley from tractor supply and one of the two v pulleys from the old setup. Now of course the new/old belt drive is showing it's use and needs a seal at the output shaft. Ordered a new bearing to go with it so we need to wait. The leaking oil ends up right on the belt, causing it to slip.

[Jim Becker]

Lets see if I can explain this so it makes sense.

The oil seal on the pulley output shaft runs on a machine bushing that is slid over the shaft. The bushing is held in place by the hub of the belt pulley. The regular equipment pulley is held on the shaft by a cap screw in the end of the shaft. If the pulley is not holding the bushing in place, it will leak oil. Your pulley is held on the shaft with a tapered hub, which is fine. However, you still need to make sure the bushing is being held tightly in place.

[rusty9930]

Jim Thanks you're correct in the description. Wish I had pictures of what I did. The seal I ordered was just that, an oil seal. When I took it all apart the bushing you mentioned had an oil seal as part of it, I think as I didn't separate them. I installed the new oil seal and the old bushing - there was space for it all without having anything protruding. There were 2 metal shims and a gasket beneath the hub which I reinstalled. When I was in there there was dirt in an oil drain channel which I cleaned out. It appears that oil will splash on the shaft to lube the bearing from the inside and this channel would be for the oil to return to the sump(?). I've mowed some with the rig twice now and it seems to be functioning OK. The deck has lost some structural integrity from rust which I need to get repaired. The overall mower works well once the height is set properly. The wheels on the deck need restored also as there is no height adjustment for them, ( they don't match the ones in the manual at all). I appreciate your input!