Service Manual

Greensmaster 3320/3420 Hydraulic SystemPage 5 − 33
This test measures piston pump output (flow). During
this test, pump load is created at the flowmeter using the
adjustable load valve on the tester.
Procedure for Piston (Traction) Pump Flow
Test:
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately ten
(10) minutes.
2. Park machine on a level surface with the cutting units
lowered and off. Make sure engine is off. Make sure the
hydraulic tank is full.
CAUTION
Prevent personal injury and/or damage to equip-
ment. Read all WARNINGS, CAUTIONS and Pre-
cautions for Hydraulic Testing at the beginning
of this section.
3. Make sure the traction pedal is adjusted to the neu-
tral position. Also, make sure that transport speed is
properly adjusted.
4. Block up front wheels off the ground (also rear wheel
if machine is equipped with 3WD) to allow flow through
the traction circuit.
5. Thoroughly clean junction of hydraulic hose and up-
per hydraulic fitting on front side of piston pump (forward
port). Disconnect hose from upper pump fitting.
IMPORTANT: Traction circuit flow for Greensmas-
ter TriFlex Hybrid machines is approximately 17
GPM (65 LPM). Use 40 GPM Hydraulic Tester
#AT40002 (pressure and flow) for this test (see Spe-
cial Tools in this chapter).
6. Install 40 GPM Hydraulic Tester #AT40002 (pres-
sure and flow) in series between piston pump fitting and
disconnected hose to allow flow from piston pump to
tester. Use hydraulic hose kit (see Special Tools in this
chapter) to connect tester to machine. Make sure that fit-
ting and hose connections are properly tightened. Also,
make sure the flow control valve on tester is fully open.
7. After installing tester, start engine and run at low idle
speed. Check for hydraulic leakage and correct before
proceeding with test.
8. Move functional lever to the transport position.
CAUTION
Wheels off the ground will be rotating during this
test. Make sure machine is properly supported
so it will not move and accidentally fall to prevent
injuring anyone near the machine.
9. Move throttle so engine is running at high idle speed.
10.Slowly push traction pedal to fully forward position.
Keep pedal fully depressed in the forward position.
11.Have second person carefully watch pressure gauge
on tester while slowly closing the flow control valve until
1000 PSI (69 bar) is obtained. Verify with a phototac that
the engine speed has not changed.
NOTE: If engine speed drops, piston pump flow will de-
crease.
12.Observe flow gauge. If piston pump is in good condi-
tion, flow indication should be approximately 17.1 GPM
(64.7 LPM).
13.Release traction pedal, open control valve on tester,
move throttle to low idle speed and turn off engine. Re-
cord test results.
14.If flow is less than 15.3 GPM (57.9 LPM), consider
the following:
A. The traction pedal and/or traction speed may
need adjustment.
B. The piston pump needs to be repaired or re-
placed as necessary.
C. Make necessary repairs before performing addi-
tional hydraulic traction circuit tests.
15.When piston pump flow testing is complete, discon-
nect tester from pump fitting and hose. Connect hydrau-
lic hose to pump fitting.
Hydraulic
System