Farmall Cub

Folks,
A bit of history of the repair:
The Cub came to me with a pressure plate with two working fingers, the third MIA, not to be found. The mounting for the third finger was busted, so the pressure plate base was not useable.

I had a used pressure plate on the shelf and I salvaged the three best fingers and assembled a functional pressure plate. Polished the PP and flywheel surfaces before installing the flywheel, clutch and PP. Adjusted all three fingers to 1.25”. A new TOB was installed, after some time marinating in a ziploc bag with plenty of oil. The driveshaft pilot bushing was not replaced, but it was given a liberal coating of oil.

The cub was put back together and clutch pedal free travel was adjusted to 1”. The Cub starts easily and no funky sounds from the bellhousing.

The problem:
When pushing the clutch in to shift gears, the clutch pedal bottoms out at about 2 to 3 inches of travel (including the free travel), not near what I would consider normal. The transmission can be shifted from neutral with a grinding of the gears. I did not release the clutch because I was in a confined area and was not sure what might happen, given the unusual operation of the clutch. Got the creeper out and examined the TOB/clutch finger interface finding a 1/8” gap as needed.

I’m stumped, why the short travel distance for the clutch pedal? I thought that I dotted all the Is and crossed all the Ts.
Your thoughts/suggestions are welcomed and, as always, very much appreciated.

Bill

Anything unusual looking with the TOB carrier assembly?

What year Cub or which clutch pedal adjusting system do you have?

I adjusted my pedal free travel to about 3/4".

Don McCombs wrote:Anything unusual looking with the TOB carrier assembly?

No, I made sure that the hanger holes and the TOB holes were not worn excessively. I did put the hanger parts in the press and removed a slight bow to square it up. The hanger rod did not show wear either.

Eugene wrote:What year Cub or which clutch pedal adjusting system do you have?

I adjusted my pedal free travel to about 3/4".

My clutch pedal is adjusted on the clutch pedal, under the floorboard (thankfully). I’m, at this point, not ready to adjust the free travel. I’m most concerned about the pedal not making a full stroke to very near the stop on the torque tube.

Bill

I have no idea if this could even cause that problem, but is there any chance you put the pressure plate in wrong side around...with the splined extended part facing forward rather than rearward?

I might start with a diagnostic step:
- Doublecheck current adjustment of 1/8 at fingers and 1 at pedal.
- Take close reading of how far the pedal moves to the point it bottoms out.
- Scrounge up a spacer to fill the 1/8 gap between the fingers and throwout bearing (hardboard scrap, wooden lath, whatever).
- Take a new reading of how far the pedal moves.
If the pedal movement is the same, you have a problem somewhere from the pedal to the throwout bearing. If it now moves about an inch less, the trouble is in the clutch assembly.

I'm ignoring the possibility that the throwout bearing and fingers are somehow binding with each other. But you can probably see that happen by looking in the hand hole and working the pedal.

you have a pressure plate issue

Dale Finch wrote:I have no idea if this could even cause that problem, but is there any chance you put the pressure plate in wrong side around...with the splined extended part facing forward rather than rearward?

I’m sure you’re referring to the clutch. I knew there was a right way and a wrong way, unfortunately I don’t have any confidence in my answer. Sooooo......

Jim Becker wrote:I might start with a diagnostic step:
- Doublecheck current adjustment of 1/8 at fingers and 1 at pedal.
- Take close reading of how far the pedal moves to the point it bottoms out.
- Scrounge up a spacer to fill the 1/8 gap between the fingers and throwout bearing (hardboard scrap, wooden lath, whatever).
- Take a new reading of how far the pedal moves.
If the pedal movement is the same, you have a problem somewhere from the pedal to the throwout bearing. If it now moves about an inch less, the trouble is in the clutch assembly.

I'm ignoring the possibility that the throwout bearing and fingers are somehow binding with each other. But you can probably see that happen by looking in the hand hole and working the pedal.

I’ll check those out tomorrow (provided my back cooperates). Given my hesitation to answer Dale’s question, I think I know what is in my very near future.

Thanks for your quick responses.

Bill

tst wrote:you have a pressure plate issue

Pressure plate or clutch, looks like a split is in my near future. Thanks, Tim.

Bill

Bill Hudson wrote:

tst wrote:you have a pressure plate issue

Pressure plate or clutch, looks like a split is in my near future. Thanks, Tim.

Bill

Well, Tim and others were right. I DO have a pressure plate issue. I have had the Cub together and apart three times (yes, the clutch was in backwards, now in properly), with the PP fingers adjusted at 1.25" or 1.125" with essentially the same result. The clutch will not fully depress the fingers (the clutch works smoothly while pulled apart, the resistance is in the PP). When the clutch pedal stops it is a firm stop, and if you try to push the clutch further, it simply bends the TOB hanger. There is no finger movement beyond the firm stop (observed through the inspection hole while another person was operating the clutch).

Careful inspection of the PP assembly reveals that there is, what seems to be a stop, machined into each of the three posts that hold the PP fingers. These stops hit the top plate of the PP to limit the finger travel. All three stops are within about a strong 1/32" of the stopping point when the clutch fingers are adjusted.

The PP is a combination of two units used to make one good one. They are both Rockford OEM units.

What am I missing, because this is not working properly?

Thanks for your help. I'm stumped.

Bill

Hi,
It sounds like there is some difference between the 2 pressure plates, and it doesn't work right when you change parts from one to the other. But without being there to see them, it's hard to know.

If you can't get it to work by grinding metal off something that is hitting, maybe you will need to buy a new pressure plate.
Be careful if grinding to not weaken something by making it too thin.

I would take the pp apart and compare the parts to see that they are the same

This may not even be possible or not make any difference on final adjustment but did anyone know there is 2 different TOB carriers. Here's the difference from TM's pics

and


Rick

I would think if the 1/8" clearance can be reached between the TOB and fingers, it must have the correct one in there, BUT if you can achieve the correct adjustment with both and the holes are at different distances, that could produce a different swing and cause farther travel with one over the other. Just a thought.

Another possibility. Since this cub came to you broke, do you know for sure the owner didn't break things and do some replacing of parts? Looks like a bunch of possibilities on installing wrong parts or installing parts incorrectly. Looks like this part can be installed backwards


Could have these parts mixed up



and the carrier I showed earlier. If the pressure plates check out the exact same, might have to explore elsewhere to make sure all the parts are correct.