851 No Lift

[ccduke]

I've got a 1962 851 that has the 'no lift' problem. I am going to follow the roadmap in the shop manual today after work. I have opened the fill port to look in, and see no fluid movement. Is there anything in particular I should be looking for? If there's no fluid movement visible, what are likely culprits?

I've got questions, though. When I got the tractor, the hydraulic fluid was milky. So, I changed it, replaced with 2 gallons of 134D. When troubleshooting yesterday, I opened the port on the pump to ensure that it was primed, and milky fluid came out. So, I made an inspection tube from some plumbing parts and a length of clear plastic tubing, screwed that into the pump port and started it up. The fluid looks just like the stuff I drained out. WHAT?! How can that be?
I then read that the rear end or tranny might be leaking into the hydraulic reservoir. How can that be? Are they not separate reservoirs?

Also, in case it's important, it has external hydraulics installed.

Thanks in advance.
Carson

 

[JMOR]

(quoted from post at 12:24:33 07/18/22) I've got a 1962 851 that has the 'no lift' problem. I am going to follow the roadmap in the shop manual today after work. I have opened the fill port to look in, and see no fluid movement. Is there anything in particular I should be looking for? If there's no fluid movement visible, what are likely culprits?

I've got questions, though. When I got the tractor, the hydraulic fluid was milky. So, I changed it, replaced with 2 gallons of 134D. When troubleshooting yesterday, I opened the port on the pump to ensure that it was primed, and milky fluid came out. So, I made an inspection tube from some plumbing parts and a length of clear plastic tubing, screwed that into the pump port and started it up. The fluid looks just like the stuff I drained out. WHAT?! How can that be?
I then read that the rear end or tranny might be leaking into the hydraulic reservoir. How can that be? Are they not separate reservoirs?

Also, in case it's important, it has external hydraulics installed.

Thanks in advance.
Carson

eals around drive & Pto shafts are the only thing keeping the compartments separated. Seal leak....sometimes , and those are "only" 60 years old. :roll:

 

[shaun wallace]

The 1/2 gallon that didnt drain out discolored the new fluid.

 

[ccduke]

So, how to drain *all* the fluid?

 

[ccduke]

I'm guessing it a non-trivial job to replace those seals. I've read that putting 134D in the read end, rather than 80w/90 will keep the hydraulics working even if the rear end leaks into the hydraulics. Doesn't it matter that the hydraulics would be (or could be) overfilled?

 

[shaun wallace]

To get all the oil out requires a split between trans/ R A and to replace seals in trans and R/A also requires split.

 

[ccduke]

Thanks.
Not really planning to split the tractor, so that'll have to wait 'til I need a clutch. I do need to get the hydraulics working. I'll report back after starting the no-lift roadmap from the shop manual.

 

[ccduke]

Well, It turned out to be the unloader valve. It was stuck tight. Spent most of yesterday on it. All in all, it wasn't too bad of a job. Worst part was, the last time somebody had the top lid off, they used a gasket, plus some kind of gasket sealer on both sides that had all bonded together with the block and the lid. Very difficult to remove.