Need thoughts on a 7020

Hey all,

I am looking at a 7020 that apparently was a little bit of a basket case for the previous owner.

First he bought the tractor, then the engine went down. had the local to him Allis Dealer rebuild the engine, supposedly major inframe rebuild.

Then, the PTO went out, so he had the PTO rebuilt.

Then, the Power Director transmission quit, so he threw in the towel and parked it. Sat for 10 years plus outside (luckily in arid western KS, where 20 inches of precip is the supposed normal, but we usually get much less than that) and our tractor jockey buddy bought it. (reputable guy, will tell you everything he was told, we have bought 10+ allis' from him)

Also, it appears that early in life before the last owner bought it, the rear end might have been swapped? The only reason I wonder this is because there is no serial number on the rear end, perfectly flat and no signs of buffing, bare metal. I am thinking the dealer forgot to stamp the numbers in the new housing.

Going off the nice radius cut in the frame rail for the lift pump filter (only last year was factory installed LP), and the nov. or dec of 80 date on one of the engine castings, I am believing it to be a 81.

So, I ask you guys,

1) Why would the transmission quit pulling?
a) transmission dipstick is not showing, could it be as simple as a seal between hyd. pumps emptied the housing and with no oil, the PD clutch would not pull?
b)with an inframe major, could the rear seal have went out and puked oil on the torque limiter and caused it to slip?
c) what are the chances there is major transmission damage? will the PD quit pulling long before any bearings are starved of oil? Does it hurt the PD to run out of oil?

2) Is it common for replacement rear ends to not get stamped? I hope the tractor was never stolen in its life, but its perfectly smooth and square metal in the proper area, so I am hoping someone just forgot to stamp it.

3) Whats it worth? as-is, the guy wants 2 grand, so I am thinking of jumping on it. he has not heard it run though. it has 4 GY Dyna Torque II 18.4x38 bias tires at 60-70 percent, and is fairly optioned out, has the aux. fuel tank and long axles with 9 bolt duals, although I dont think it has Stadium lights. No weights.

Any info appreciated,
Thanks!

I think I'd get it, shoot ya could even spend a little on it to find what the problem is, if it looks like it will turn into a money pit, ya can prolly get most your money back parting it out. I'd think a good running engine would be worth at least $1500-2000, rear tires/with hub duals about the same...all the other parts would go in your pocket..but if its a simple fix, even if ya hafta split it, ya gots a $7500-10,000 workin machine

Its most likely the torque limiter, being they did an inframe rebuild it would not have gotten replaced at that time. Do the hydraulics work?
If they do then its a problem with the PD, or low oil in the transmission. BTW it is very unusual for the PTO clutch to give trouble, almost unheard of unless really abused.

Yes, there is a seal between the gerotor and gear pump, it isn't real common but yes it can pump the transmission oil into the rear end. PTO clutch pressure comes from the piston pump so its not affected by the trans running low, as far as steep slopes, I doubt that would have caused any problems unless rear end was really low, and then he would have noticed the steering acting up also.

OK, new info.

Our tractor jockey buddy decided to call the previous owner to do a little research to see specifically what might be wrong, and the guy who sold the tractor provided some new info that he had not shared prior.

Supposedly tranny is fine, but the tractor was parked because "It would not pull itself and would drive in circles"

The tractor seller has a slight alcohol problem, so that is why info is new and is suddenly remembered. :)

So I guess it could be rear end issues or something as simple as the steering spool?

THe wheels were pointed straight when he bought it, so I dont think he meant the steering hyd, but that is not out of the question.

What all could go wrong in the rear that would cause driving in circles?

what would happen if the differential carrier cut itself in half from the two pinions galling?