Jacobsen HR5111 Service And Repair Instructions page 178

REAR TRACTION MOTOR TEST
Left Motor Test (See Figure 8R-14)
NOTE
A traction pump, traction motor and a 4 wheel
drive valve test must be performed before pro-
ceeding with this test.
29. At the 4 wheel drive valve, connect left motor hose
to L1 port.
30. Install rear wheel restraints to the right and left rear
wheels.
31. Open tester load valve, start engine, advance throt-
tle to 2800 engine rpm.
32. Engage 4 wheel drive switch.
33. Set parking brake, apply and hold foot brake.
34. Slowly close tester load valve until 3000 psi is
obtained and allow oil to heat up to 150°F.
35. Read/record gpm flow. Subtract from flow obtained
in 4 wheel drive valve test. Record engine rpm.
•
If flow drops 1/2 gpm or less, left rear motor is
okay.
•
If flow drop is 1/2–1 gpm, left rear motor is mar-
ginal.
•
If flow drops more than 1 gpm, left rear motor
has excessive internal leakage.
Right Motor Test
36. At the 4 wheel drive valve, connect right motor
hose to R1 port.
37. Open tester load valve, start engine, advance throt-
tle to 2800 engine rpm.
38. Engage 4 wheel drive switch.
39. Set parking brake, apply and hold foot brake.
SECTION 8R. INSTRUMENT TEST
40. Slowly close tester load valve until 3000 psi is ob-
tained and allow oil to heat up to 150°F.
41. Read/record gpm flow. Subtract from flow obtained
for the left rear motor test. Record engine rpm.
•
If flow drops 1/2 gpm or less, valve is okay.
•
If flow drop is 1/2–1 gpm, valve is marginal.
•
If flow drops more than 1 gpm, valve has exces-
sive internal leakage.
HYDRAULICS
Figure 8R-14. Rear Traction Motor Test
8R-14