Just bought a Farmall H with a front loader a few months ago and it ran fine until the second time I tried to use it in snow. I got it started and moved it about 50 ft when I felt and heard a loud clunk and it slipped out of first gear. At first the engine would stall when I released the clutch. After a few tries, I got it back in gear and drove it another 100 ft then used the loader to scoop a bucket of snow. This time when I changed gears, I heard and felt the same clunk and the engine stalled every time I tried to release the clutch. The shifter changes gears and the tractor can roll back and forward no problem. In fact I used my 4x4 to tow it back out of the road and up onto my property again.

Can anybody tell me whats wrong here and how to fix it? Thanks.

It seems like I have the exact same problem as this other post: https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=farmall&th=639112. I was just wondering if billde could complete the list that he started? I'm going to try the suggestion of melting the ice out, but it may be more than that with mine because I heard and felt a clunk before it stopped working. I hope someone here can give me some good ideas. My tractor is a Farmall H from 1946, and this will be my first time working on a tractor since I was a teenager.

Is there an easy way to check that? I don't have a hoist or a cherry picker to lift the cover plate.

[Update]

I reheated it again, and drained the transmission oil. It looked like milk chocolate. I must have lost quite a lot earlier, because only around 3 gallons drained out so far. That might explain one of the other symptoms I had been noticing - the transmission would pop out of 1st gear as I drove along if there was any kind of strain on the tractor, but not unloaded on straight level ground.

The transmission might need some new bearings and the ball detents on the shift rails may be rusted to dust. If it pops out of any gear, it will continue to do so. Best of luck. Running that low on Lube and with water in it, is a rust reality. Jim

It could also be in two gears at once. You should be able to remove the shift lever and look down inside at the rails. There should be a groove for the end of the shift lever across all three rails--if in neutral it should line up on all 3. On my H the detent springs were broken and the shift rails would move around on their own. This especially happened when shifting out of 1st. The R/1 shift rail would keep sliding and put the tractor in reverse. When this happened, releasing the clutch pedal/engaging the clutch with the tractor in any forward gear would cause the tractor to immediately stall. Putting the tractor in neutral and releasing the clutch pedal/engaging the clutch and the tractor would start moving in reverse. You can check for this by releasing the clutch pedal in neutral. Be careful as the tractor may immediately start to move if it is stuck in gear. Dave

Knocking tooth sounds are a sure bet to at least look at the trans before operating the tractor. Things can be looked at through the belt pully drive hole (if no pulley drive, easy, if a drive it needs to be taken off. The two center housing bolts need to be left in the holes. Once off, a good light, and spinning the parts to look at every tooth is the only answer. Jim

Thanks I'll do that, especially since I'm draining all the oil and replacing it anyway.

And before anyone says anything no the rocket heater had been shut off for 10 minutes before I ever went over there to open the drain plug and drain the oil.

I still have to go to the front plug.

If the shifting parts are moving the gears to neutral and tractor will roll you have something keeping the bottom shaft in transmission from turning. Could be ice in lower transmission housing but maybe not since the bull gears will turn when you pull it. Could be bearing parts or something else locking the input shaft and constant mesh gear, or the hydraulic pump locked. Could try putting the PTO in gear and see if trying to turn it back and forth will free something. If it does more checking will be needed to make sure more damage doesn't happen before use.

It is a good bet that there was some ice in the bottom of the rear end and a chunk of it has moved , jamming the rear gears. Heat the rear end with a heater of some kind , open the drain plug and water will run out ahead of the transmission gear oil. I have two H's and one of them did what you described. Once the weather turned warm I drained both H's of their water and got over a gallon out of one and about two gallons out of the other. I went to look at an H for sale and told the guy it had water in the rear end , he didn't believe me so I got a wrench out of the truck and a pail and I drained it for him , he was awed by the amount of water. I'm betting water (frozen) is your problem

Thanks Michael Soldan,

Heating the differential and transmission from the rear with a torpedo or rocket style space heater of about 150,000 BTU's did the trick in pretty short order.

I heated it for around 45 minutes, then opened the drain plug. A little clear water came out then there was a gush of dirty brown fluid.

I closed the drain plug as quickly as possible, but there was a pretty good gush going on. Over a half gallon of the Brown stuff escaped. I don't know what the transmission or differential fluid is supposed to look like, but I doubt it was supposed to be that color.

Anyway, after I got the plug closed, it started right up without depressing the clutch pedal. I drove it a short distance, but it was making noise like gear teeth knocking together so I shut it down. I figure I now need to replace the fluid.

When water and old gear oil mix it looks like carmel , a muddy brown colour. There is a chance that H has never had a fluid change in years. My recommendation is to completely drain it and then refill with the proper gear oil. Also , when you fill it it will leak. Under the belly pan cover you can see the drive shaft. The seal on the drive shaft to the rear end usually leaks because of age and wear. The seal is easy to change and not expensive , if the shaft is worn a speedi sleeve will fix it with a new seal. It is an easy job with a few tools. Good luck with your H

Trying this now: I have one of those rocket style heaters which I will point at the bottom back end of the tractor for a while and open the drain plug to see if that does the trick

Hello Farmboy welcome to YT! First we need to get terminology set straight so we are all on the same page. Your title says ...release(disengage) A clutch allows the transfer of rotating force to be interrupted. So in mechanic terms in the case of a clutch operated by a foot pedal as on an H the clutch is engaged when its parts are coupling and rotation is transferred. So this happens when the clutch pedal is released to its normal position or no foot on it. The clutch is disengaged when the pedal is held down and the rotation through it is interrupted or stopped. It seems your scenario is slightly different then in the one of the link of the post you added. Although the outcome of their issue was not disclosed. If your tractor was stuck in two gears at the same time you would not be able to tow it anywhere without a rear wheel sliding. I assume you have tried to drive the tractor again after you towed it back on your property? If your I understand your explanation correctly you may have locked up a one of the upper front transmission bearings or a lower transmission shaft bearing or something has gotten in your lower transmission shaft gears and locked them up. There also is a small possibility that the drive coupler, number 17 in the attached parts diagram has come apart and is lodged against the case an will not let the clutch shaft turn. I assume since you mentioned hydraulics that you have a belly pump. You can see the clutch coupler if you remove the access plate which is a thinner plate on the bottom of the tractor slightly ahead of the pedals.

• H clutch shaft area parts diagram

Thank you for your response. I would have never thought of it that way. I released the pedal, which should have coupled the power from the engine to the transmission, but instead stalled the engine and showed no apparent transfer of power through the transmission and differential to the rear wheels.

I don't know much but I do know this; to remove the transmission top cover, it is really heavy, and it'd be best to use a hoist from the ceiling joists to winch it straight up into the air. Carefully avoid damage to the shifter linkages. Also carefully slowly lower it. The older you are the heavier it will be.

I hope I don't have to do that any time soon. I don't have anything that I can use overhead. I appreciate the "older" comment, I still sometimes try to do things as though I was 40 years younger