Hi there, I have been reading a lot about this transmission. I recently aquired a 1997 cat 140H grader with serial 2ZK01865. Now when i bought this machine it wasn't moving at all, no gears forward or backwards. So i took the transmission out and apart and found 2 sets of clutch packs burnt to a crisp. So i ordered all new clutch packs and piston plungers and gears for this transmission and it wasn't cheap but i said i'm gonna try and do this right once and done. Well i got it all back together and have all my gears forward and reverse but it wants to creep forward all the time. When i first start the machine it sits still for about 45sec and then it starts to go forward. I did some pressure test and found i have no pressure on C test port when in 2F and 3F. I have also bought all new solinoids complete and changed all of them. Also i took valve body apart to get get all clutch stuff out of it and now i'm wondering if something is not in the right place. Is there any way i can check this for the issue?
A bit late to be asking that question. You really needed all the info you are asking ab out BEFORE the control valve was disassembled. See the attached. First questions: 1. Did you disassemble the control valve and clean it.? Were the orifices/screens (3 from memory) in it replaced.? Were all the springs checked against specs and replaced if necessary.? 2. Were all the internal passages in the clutch shafts cleaned out with brake/contact cleaner.? What about the orifice that feeds the balance piston for #7 clutch.? Was that cleaned out.?
It looking like i have to take valve body back off. I don't have a spring pressure gauge but i can measure the springs before compressed.
Measuring the free length will get you close enough. Look for the stripe colour on the springs to get the correct location for each one. If anywhere around 50% of the springs are out of spec then I would suggest that you replace them all while you are in there. Replace all 4 highlighted orifices in the parts list if you haven’t done so already. I would also recommend new O-Rings right the way through the valve body and a new transmission wiring harness - the short one that is zip-tied to a steel “ladder” frame mounted on the control valve. Certainly do that if you have installed all new solenoid valves. There is also an update in the control valve to the springs for #7 clutch station that I think applied to your transmission. Let me look it up. If it does apply I strongly recommend that you do it while you have the control valve disassembled. I have a bad feeling that, despite all the above, the transmission is going to have to come out again because I’ll almost guarantee it wasn’t completely cleaned out in all the hidden nooks & crannies.
It does apply to all 2ZK-prefix machines. See Service Mag SEPD0936 attached for the reasons behind the update and the parts required.
See the attached.
So with the information you have givin me. Would it be safe to just take the valve body back off and check the springs and put new orifice in the 3 locations and do the #7 update spring upgrade? The biggest thing bothering me is the only 50 psi on C test port when i'm in 2F and wondering if that has anything to do with the creeping?
I think you have to start somewhere and pulling the valve off and going right through it to verify springs, orifices, etc, is probably the first logical step. Once you have the valve reassembled and back on the transmission there is the small matter of setting initial pressures. That is the first step before actually measuring clutch pressures. I can walk you through the process when you get to that point.