TM-9-2320-272-10

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; OPERATOR'S MANUAL

SEPTEMBER 2004

CHANGE 2

TM-9-2320-272-10 - Page 313 of 481

TM 9-2320-272-10

2-204

(1)

Start engine when engine coolant temperature reads 120°F (49°C) or

higher as indicated by engine coolant temperature gauge (1). Refer to paragraph 2-

13 for cold weather starting instructions.

(2)

Check instrument readings. If any reading is not normal, stop engine.

Report condition(s) to organizational maintenance if operator troubleshooting (table

3-1) cannot correct malfunction. Normal instrument readings are:

(a)

Engine oil pressure gauge (7) should read 15 psi (103 kPa) on

M939/A1 series vehicles and 10 psi (69 kPa) on M939A2 series vehicles, or higher

with engine idling.

(b)

Air pressure gauges (2) should read 90-130 psi (621-896 kPa).

(c)

Voltmeter (3) should read in green area.

(d)

Engine coolant temperature gauge (1) should read 175°-200°F

(79°-93°C).

d.

Driving Vehicle.

CAUTION

Do not allow the M939 series

vehicles to exceed 5 mph (8

km/h) or M939A1/A2 series

vehicles to exceed 6 mph (10

km/h) when transfer case is in

low and the transmission is in 1

(first). Failure to do so will

result in damage to internal

engine components.

(1)

Drive slowly with transfer

case shift lever (5) in low range and

transmission selector lever (4) in 1 (first)

for 100 yd (91 m). This should be enough

time to warm up gearcases and tires.

(2)

Check instruments during

operation. Refer to step 2c for normal

readings. Transmission oil temperature

gauge (6) under should read 120-220°F

(49°-104°C) for normal operation.

2-32. OPERATING IN EXTREME COLD (Contd)