It's the standard symptom. Loss of forward speed while reverse speed is normal. My TorqMotor "rebuild" was simply to sand and polish each layer on a surface plate on wetted sandpaper. I started at 320 and went up to 1500 grit. I followed the Parker HY13-1512--06_Service_Torqmotor_TB-TH.pdf instructions. The were no scratches or any sign of abnormal wear but went ahead having taken the motor apart anyway. I checked the measurements of the rotor and vanes with a micrometer. I had no specs to go by so just compared various readings and found less than .001 difference. The vanes were so tight I had to follow the special instruction for assembling the rotor. I installed all new seals from the service kit. My 3016 has the 7 bolt motor Figure 5 page 12 in the Hydraulic Motor Manual 9-99644_watermarked.pdf. I had to separate the transaxle from the tractor frame to get at the TorqMotor mounting bolts so I had the chance to inspect the transmission. All looked brand new except for a little sludge in the bottom of the box.
Next I cleaned, disassembled, and reassembled the C33473 control valve following the Ingersoll Control Valve Service Manual 9-50382. All O-rings were replaced. All ball bearing valve seats and springs looked good. The travel and lift spools had no scoring and fit nicely without the O-rings installed. I expected the travel spool to be worn. The holding spool was scored on all lobes but felt snug without the o-rings. I flipped the spool end to end and reinstalled. In hind sight maybe I should have swapped the holding valve end caps and springs as well. The tractor was put back together and oil added to 6" from the top of reservoir. The oil level didn't go down much after starting the engine and cycling the lift valve, rear attachment valve and finally the drive valve. As expected I needed to adjust the travel relief valve having guessed at where it was set before disassembly. Success! At the top of the driveway I had what seemed to be the same forward and reverse speed. Then I went down a hill on the lawn and back up. It was right back to little forward speed as before, maybe less! It has tapered off to less forward speed than ever. I don't hear the relief valve opening but I do when trying to move forward in high gear. The lift relief squeals it bit more than it always did.
So, my thoughts for next steps.
1. Try tightening down on the transmission relief valve.
2. Stretch the holding valve springs and reinstall. (I forgot to mention the holding valve wasn't maintainging speed on downward slopes of > 15 degrees.)
3. Swap out the metal pipes from the TCV to hydraulic motor with flexible hose and switch the connections. (I'd eventually get used to shifting reverse to go forward and vice versa.)
4. Do all 4 above?
jbadman - You mentioned circuit leak testing with a flowmeter. How and where can I get that done?
P.S. I got some great documents I've gathered along this trek through Death Valley but being a newbie can't post them. Any suggestions on getting them into the Technical Library?
