TM 5-3805-262-34
TEST NO. 2 - LOADER CIRCUITS AND MAIN RELIEF VALVE (SHEET 3 OF 4)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
Press and hold flowmeter TEMPERATURE switch and watch flowmeter TEMPERA-
TURE gage. Gage should indicate 130 degrees. If indication is not correct
go to step (12) below; if gage indicates 130 degrees go to step (13) be-
low.
Press accelerator pedal and increase engine speed to 1500 rpm. Hold BUCK-
ET control lever in CROWD position. Close flowmeter PRESSURE VALVE con-
trol until flowmeter PRESSURE gage indicates 1000 psi. Watch flowmeter
TEMPERATURE gage while depressing flowmeter TEMPERATURE switch. Continue
to operate engine at 1500 rpm until flowmeter gage indicates 130 degrees
then release accelerator pedal.
Increase engine speed to full throttle.
Hold BUCKET control lever in CROWD position and slowly close flowmeter
PRESSURE VALVE control. As PRESSURE VALVE control is closed, flowmeter
FLOW gage indication will slowly decrease. When loader main relief valve
begins to open, flowmeter FLOW gage reading will decrease rapidly. Stop
closing flowmeter PRESSURE VALVE control and record flowmeter PRESSURE
gage reading. This reading is the pressure at which main relief valve be-
gins to open.
Continue to operate engine at full throttle. Hold BUCKET control lever in
CROWD position and close flowmeter PRESSURE VALVE control. Record flow-
meter PRESSURE gage reading. This reading is the pressure at which main
relief valve is completely open.
Open flowmeter PRESSURE VALVE control completely and turn off engine.
If reading recorded in step (14) above is less than 2025 psi, parts in
control valve assembly main relief valve are worn or damaged. Replace
control valve assembly (page 3-647) and repair (main relief valve is
defective and must be replaced or repaired).
If reading recorded in step (15) above is not 2250 to 2350 psi, adjust
control valve assembly main relief valve (page 3-617).
Start and operate engine at 2000 rpm.
Hold BUCKET control lever in CROWD position and close flowmeter PRESSURE
VALVE control until flowmeter PRESSURE gage indicates 2000 psi. If neces-
sary, adjust engine speed to 2000 rpm by further depressing accelerator
pedal. Record flowmeter FLOW gage reading.
Raise bucket by placing LIFT ARM control lever in RAISE position until
bucket can be dumped.
Hold BUCKET control lever in DUMP position and adjust flowmeter PRESSURE
VALVE control until flowmeter PRESSURE gage indicates 2000 psi. If neces-
sary, adjust engine speed to 2000 rpm by further depressing accelerator
pedal. Record flowmeter FLOW gage reading.
3-633
