Hello- I bought a 97 D3 C (serial number 4KS00347) for our farm. It is the joystick steer type. Problem is when you start it, you have to push the blade down to disengage the pump or the left track pulls and it goes in a circle. When you push down on the blade to take pressure off, it works fine. Where would you start to diagnose this problem? It is the joystick? It looks new as if someone has replaced it already. Are there relief valves on this machine somewhere that could be stuck? It has good power on both tracks and seems to be a strong machine. Any ideas are appreciated!
You say that you have to push the blade control down to somehow unload the implement pump in order to start the engine. Questions: 1. Once you have the engine running does the implement hydraulic system respond normally.? In other words do the raise, lower, hold, and float commands all work as you would expect them to work.? 2. Do you have a manual for it yet.? If not you really need to get hold of one ASAP. 3. Does the speed/direction control on your particular tractor have the optional Speed Hold Control lever (arrowed).?
Once it starts it responds properly. It's basically on start-up it does this. I do not have the system you pictured. It is simply a joystick control with no additional levers. I know there are plunger ports (not sure the technical name) in the valve controlled by the joystick. I was told they sometimes wear out or stick. However, where does the line from the joystick valve go to? Does it go to another valve or somewhere else? I will purchase a manual! Just looking for advise on where to start. Thanks again for your help!!
Based on your comment that the joystick appears to have been replaced the first thing I would suggest is to make a neutral adjustment. See the illustration below. 1. Lift up the boot on the joystick. 2. Raise the transmission lock lever (43) to the UNLOCKED position. 3. Push the joystick all the way FORWARD until it stops. 4. Lower the transmission lock lever (43) to the LOCKED position. 5. The joystick should automatically return to Neutral. The pilot valve plungers should not be depressed. The plungers are located just below the joystick handle under the boot. Loosen the two bolts (39) and adjust the plate (42) if the plungers are depressed. The joystick should return automatically to the neutral position whenever the Transmission Lock Lever is moved to the LOCKED (DOWN) position. 6. Repeat the Steps 2 thru 5 but this time push the joystick to the REAR in step 3. 7. Tighten the top two 8T-4136 Bolt (39) to a torque of 55 ± 10 N·m (40.6 ± 7.4 lb ft).
If the above adjustments do not give the desired result then I would suggest that the next step would be to remove the pilot valve located underneath the joystick and disassemble it looking for sticking plungers, etc. Attached are the instructions for that task. Please note that the assembly includes shims in four critical locations. Take care to ensure that all parts including shims are labelled during disassembly and reinstalled in exactly the same locations from which they were removed. Failure to do that could result in the valve working worse afterwards than it did before. Also there is an electrical connector to disassemble. Again take careful note of which wire goes in which location of the connector. If you have any questions please post back.
Thank you very much! I will give this a try!!