Jacobsen SLF 1880, Technical/Repair Manual

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8G-53
• If flow drops 0.5 to 1.5 gpm (1.9 to 5.6 lpm), the
left front traction motor is marginal.
• If flow drops more than 2 gpm (7.6 lpm), perfor-
mance will be noticeably reduced. The left front
traction motor will require repair or replace-
ment.
30.Open tester load valve, slow engine to idle speed
and shut off engine.
4WD VALVE FLOW TEST
31.Remove blocking disc inserted between “T” fit-
tings and 4WD valve hydraulic lines located
behind front axle and reconnect hydraulic lines to
“T” fittings. (Figure 8G-8).
32.Install blocking disc at the locations indicated in
(Figure 8G-9) to test the 4WD valve.
Figure 8G-9. 4WD Valve Flow Test
33.Open flow meter load valve, set parking brake,
reel switch off, start engine and advance throttle to
high idle position.
34.Slowly close tester load valve until 2200 psi (152
Bar) is obtained.
35.Read/record gpm (lpm) flow on Traction Circuit
Test Record (Figure 8G-13).
• If flow drops 0.5 gpm (1.9 lpm) or less, 4WD
valve is okay, proceed to Rear Traction Motor
Flow Test.
NOTICE
Before performing this test, a traction pump flow test
and front traction motor test must be performed.
Flow meter connections are maintained from traction
pump flow test with the exception of the blocking
disc being relocated. The flow lock tool should
remain in place and adjustment retained.
In Out
Blocking
Disc
4WD Valve Flow Test
Top Hydro Port
“Reverse”
Bottom Hydro Port
“Forward”
Top Hydraulic Line
“Reverse”
Bottom Hydraulic Line
“Forward”