7000 Powershift help: parts missing?

I don't believe piston seals would leak even low pressure air.Don't know anything about the trans your 7000 has but from problems it gave you and what you are seeing now with your testing I think you need to go completely through it and check each componet.Don't assume any check valve,return spring or anything is ok.Good luck.

Well, I took the little nozzle off the air hose and put some more air to it and everything started engaging when I put air to it, so I guess I didn't have enough air flow.  The grit is grayish, so I am guessing it is iron material.  The oil is darker, but doesn't smell burnt.  I just ordered 2 hydraulic filters and am planning on changing the oil.  I need to get more parts cleaner this afternoon, so when I get that, I will probably pull the plugs and spray some cleaner in there to try to flush out any junk.  The passages looked unobstructed under the plugs on the clutch housings, but I cannot see a lot.  I looked in my service manual and it wasn't really clear on which orifices had the flyballs and springs.  None of the plugs on the outer surface of the housing had flyballs/springs under them.  The manual made it look like there were plugs that were perpindicular to the outer surface that would be covered up between the housings where the spring and flyballs are.  The pacing between all the plates looks pretty equal both engaged and disengaged.  The tractor hasn't been slipping, it just wouldn't modulate very well with the inching pedal and 3rd range always had a little bit of a weird shift where it would lag then grab (not slipping, but just slam into gear).  When it was hot and running in the field for a while, sometimes it would not engage 1st range when the clutch was let out, but after working the clutch pedal in and out a bit, it would finally engage.  3rd range would also have times where the pressure light would flicker and some valve would be buzzing like crazy in the valve body.  This would usually be cured by shifting to 2nd then reshifting back to 3rd.  Also, when it was hot, the PTO would kick out when I shifted the powershift.  I am running Traveller Universal Tractor Fluid which meeds AC 821XL spec.  Is there a better fluid that is reasonable I should be running in this tractor?  I went on and ordered the gaskets and seals, so I plan on putting it together with the valve body cleaned out and fresh oil/filter to see how the tractor runs after that.   

I don't think the seals are leaking with oil, as the steady pressures check out fine.  The transmission brake looks a little different than the new one I have sitting there, as it looks like the fibers are all starting to come loose and it has absorbed oil or something, so maybe that is where all the stuff is coming from.  I don't have any weird noises or anything from the transmission, so I can't imagine a bad bearing or something.  I wonder if it's possible a previous owner didn't change the oil in it for a while and this is still the build up that was left in there?  I guess I'll clean both the powershift and the PTO valves and put everything back together with new oil and filter and see how it runs then.  The stuff seems a lot more like the friction material from the clutches than bearing materail, but I am not sure.  I may try a little higher quality fluid this time in the hydraulics like Shell UTF or maybe JD Hy-Gard. 

Thanks for the tips, DrAllis.  Is it a problem that the 2nd range clutch, the one closest to the rear of the tractor, doesn't let any air come out of the small hole where the flyball while the other two clutch packs will let air come out of those when using air to engage the clutch?  I am kind of debating whether I should tackle splitting at the transmission and pulling the torque tube to reseal the wet clutch packs.  I have changed the hydraulic fluid probably 3 times, since I have had it in 5 years and I have put 800 hours on it, but I bet it probably wasn't religiously maintained earlier in its life.  How long are the powershift packs good for in a 7000 typically, considering I do quite a bit of shifting with round baling in this tractor?  I think you are right on the regulating pressure, I believe stock is 180-210.  Do I just do that by shimming the regulator valve in the powershift valve cover?

What do you recommend for cleaning the valve body and spools?  I have been using Xylene to clean the small bits, then wiping them off and spraying with WD40 for reassembly.  For the bores, I have been using brake parts cleaner to flush them out, and then spraying them with a good coating of WD40.  Should I just put them in the dish washer when my Dad is not home?

Edited by Hurst - 16 Jul 2010 at 5:18pm