Service Manual

Multi Pro 5800Hydraulic System Page 5 − 44
Spray Pump Circuit − Gear Pump P1 Flow Test
(Using Tester with Flow Meter and Pressure Gauge)
Over a period of time, the gears and wear plates in the
gear pump can wear. A worn pump will by-pass oil and
make the pump less efficient. Eventually, enough oil can
by-pass to cause circuit performance problems. Contin-
ued operation with a worn, inefficient pump can gener-
ate excessive heat and cause damage to seals and
other components in the hydraulic system.
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately ten
(10) minutes. Make sure the hydraulic tank is full.
2. Park machine on a level surface, stop engine, en-
gage parking brake and remove key from the ignition
switch. After turning engine Off, operate all hydraulic
controls to relieve hydraulic system pressure.
3. Remove the rear undercarriage shroud (see Under-
carriage Shrouds in Chapter 9 − Chassis in this manual).
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.
4. With the engine Off, clean fitting and hydraulic hose
on left side of front gear pump section (Fig. 37). Discon-
nect hydraulic hose from the fitting.
IMPORTANT: Make sure that the oil flow indicator
arrow on the flow meter is showing that the oil will
flow from the pump, through the tester and into the
hydraulic hose.
5. Install tester with pressure gauge and flow meter in
series between the fitting and the disconnected hose.
Make sure the tester flow control valve is open.
6. After installing tester, start engine and run at low idle
speed. Check for hydraulic leakage and correct before
proceeding with test.
CAUTION
Do not close tester valve fully when perform-
ing this test. In this test, the hydraulic tester is
positioned before the circuit relief valve. Pump
damage can occur if the fluid flow is blocked
by fully closing the tester flow control valve.
1. Gear pump
2. Spray pump circuit pressure hose
3. Fitting (front gear pump section)
Figure 37
2
1
3
7. Operate the engine at high idle speed (Diesel en-
gine = 3050 to 3150 RPM, Gasoline engine = 3200
RPM).
8. Carefully watch pressure gauge on tester while slow-
ly closing the flow control valve until 800 PSI (56 bar) is
obtained. Verify engine speed with a phototac.
NOTE: If engine speed drops below specified RPM,
pump flow will decrease. Adjust test specifications ac-
cordingly (see Testing in this chapter).
9. Observe flow gauge. Flow indication should be
approximately 12 GPM (46 LPM).
10.Open tester flow control valve and stop engine. Re-
cord test results.
11. If the flow is less than 10.8 GPM (41 LPM) or a pres-
sure of 800 PSI (56 bar) could not be obtained, check
for restriction in gear pump suction line. If suction line is
not restricted, remove gear pump, inspect pump and re-
pair pump as necessary (see Gear Pump Service in this
chapter).
12.After testing is completed, remove tester and rein-
stall disconnected hose.
13.Start engine and run at low idle speed. Check for hy-
draulic leakage and correct before returning machine to
service.
14.Install the rear undercarriage shroud (see Undercar-
riage Shrouds in Chapter 9 − Chassis in this manual).