Ford NAA oddball problem?

At the moment, I am a bit stumped. If someone else described this sort of problem to me, asking for advice, I would figure there was
something missing from the story.

I have a Ford NAA/Jubilee here. I don't have any history on it. It had been sitting for years. I did some engine and wiring work on it.
Got it running. Sounded fine and ran fine when I parked it. It sat for a few months. Today I started it and tried to move it. I put it in
reverse, let the clutch up - and nothing happened. I then stuck it in 1st gear and again, nothing. No load on the engine, no attempts of
the tractor trying to move. So - I am no huge Ford expert, but as far as I know - all is gear drive with a conventional single-disk
clutch. PTO and wheel drive work off the same clutch. I got wondering if somehow the clutch had gotten stuck disengaged. So I turned on
the PTO. It worked. Stopped with the clutch pedal in and turned when I let the pedal out. I then put the tractor in gear and let the
clutch up. NOTHING, yet the PTO would spin every time I let the clutch pedal up. So it seems the clutch has to be fine. I got sitting
there watching the PTO turn while I tried to think hard on the subject. Tractor was in 1st gear while I was sitting there thinking. After
a few minutes, the tractor wheels almost seemed they wanted to start turning. Then real slowly at first, they did. Then gradually got
faster and faster until it began to work just like it ought to work. It acted almost as if I had a hydrostatic trans and I was engaging it
slowly. After that tractor got going, I ran it around a while. Even hooked it to something heavy and pulled a heavy load. So that is it.
Seems like this should not be possible and I have a screw loose in my head. Guess I will have to study this tractor some more. If
everything is gear drive - how can something act like it is slipping and slowly engage? Seems the only thing in the entire driveline is
the clutch and if that slipped - it would of showed with the PTO.

Just a theory but I'm th8nking a sticking throw out bearing. Doesnt take much to spin a pto without anything on it. If the bearing was sticking so the clutch was barely engaged the clutch might slip and not move the tractor but spin the pto. As the bearing worked its way free the clutch engaged as it is supposed to. Thats just an idea.

Dont think my original theory holds water. If clutch isnt spinning due to slippage the pto wont turn.

Are You sure that it doesnt have a sherman overdrive that is in between high and low ? Roy

Don't know whether this will apply to your problem, but, the damnest thing happened to a pickup I own which gets limited use. A friend of mine needed an extra truck one day so we fired up the old ford, well the truck started and ran just fine, except that it wouldn't move. We thought it over and came up with several situations that would explain the problem and finally the only thing to do was pull the trans. Wellllll that brought on head scratching. the bell housing, which was part of the block, was filled full as could be of acorns, hickory nut and whatever a small varmint could store in such a limited place. When the clutch was depressed the nus etc fell down between the clutch plate and flywheel and naturally wouldn't let the clutch engage. So while we had the trans out we put in new clutch parts.

Yes, it does not take much to spin the PTO with no load on it. But - when I put the tractor in gear - and let the clutch up - and the wheels
did not move - seems the PTO should of stopped too? I am not sure. Guess I will have to do more testing. This is an odd one (the problem,
that is).

Is there by chance an extra lever on the left inspection cover, besides the PTO lever? Or an extra shaft sticking out of it if the handle is gone? Don't remember where they are routed but any extra hydraulic lines going in the inspection cover too? There was an add-on hydraulic clutch that you could put in those tractors to give it a sort of live PTO that went behind the transmission. If it has that maybe it lost its prime and then slowly built up pressure. Just taking a guess! Greg NE

Yep, that's a strange one!

About all I can think something is sheared in the final drive, maybe a shaft spline or the ring gear bolts, but how it would gently start driving then hold under load is the mystery.

If it does it again, open one of the side covers, look in, see what's turning and not turning.

Two stage clutch and the one for transmission slipping, Ron MN

(quoted from post at 22:28:49 10/24/19) Two stage clutch and the one for transmission slipping, Ron MN

Click to expand...

Nice theory, but NAA's only had a single-stage clutch.

It's POSSIBLE Greg NE is on to something with the add-on hydraulic clutch pack the made for a live PTO of sorts.

That system is covered in the thread linked below, which shows the external parts that would be visible IF JD's tractor has it.

There's also a photo of a (apparently even more rare) hand-operated auxiliary clutch.

https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ford&th=522281

Sounds like the release bearing hub is hanging up in the release position with the clutch just slightly engaged.