Allied H6G, Service Manual

Page: 35 / 112

Section 2
2 - 1
Troubleshooting
General
Winch problems generally fall into one of three categories:
controls, hydraulic system, or mechanical system. Follow
the troubleshooting steps below to isolate the probable
location of the malfunction.
1. Make sure the control lever assembly (including pi-
lot controller unit) is functioning properly, with a full
range of motion.
2. Check the oil level and type. Ensure the operating
temperature range for the oil is suitable for the condi-
tions. Check the fi lter indicator.
3. Check winch hydraulic pressures. Start with control
pressures (see Figure 2-1), then check main system
pressures.
4. Inspect the winch gear train for problems.
For best operation and life, the winch oil op-
erating temperature should not exceed 180°F
(82°C). Winch oil reservoir temperature is
monitored at the dozer. The John Deere 850JR
warning light will come on at 200°F (93°C).
John Deere 850JR
Pilot Control Valve Metering Curve
0
100
200
300
400
500
600
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Lever Travel (°)
Pilot
Pressure (
p
si)
0 psi
135.3 psi
439 psi
Normal
Deviation
Figure 2-1 Output Pressures from Pilot Controller Unit on Control Lever vs.
Angle of Lever Defl ection