TM 5-2420-230-24-2
B3.9 and B5.9 Series Engines
Cooling System - Air or Combustion Gas Test (008-019)
Section 8 - Cooling System - Group 08
Page 8-19
CAUTION
The system must be filled slowly to prevent air locks.
During filling, air must be vented from the engine cool-
ant passage. The system has a fill rate of 14 liters per
minute [3.7 gallons per minute]. Do not exceed this fill
rate. Wait 2 to 3 minutes to allow air to be vented; then
add coolant to bring the level to the top.
Close all drain valves and fill the system. Use a mixture of
50-percent water and 50-percent ethlene glycol antifreeze
to provide freeze protection to -36C [-33F].
Coolant Capacity (engine only)
liters
U.S.gal
4B3.9, 4BT3.9
7
MAX
1.85
4BTA3.9
7.9
MAX
2.1
6B5.9, 6BT5.9
9
MAX
2.38
6BTA5.9
9.9
MAX
2.61
WARNING
Do not remove the pressure cap from a hot engine. Wait
until the coolant temperature is below 50C [122F]
before removing the pressure cap. Heated coolant spray
or steam can cause personal injury.
Install the pressure cap. Operate the engine until it reaches
a temperature of 80C [176F], and check for coolant
leaks.
Check the coolant level again to make sure the system is
full of coolant or that the coolant level has risen to the hot
level in the recovery bottle on the system, if so equipped.
Gas Test (008-019)
Overflow Method
WARNING
Do not remove the pressure cap from a hot engine. Wait
until the coolant temperature is below 50C [122F]
before removing the pressure cap. Heated coolant spray
or steam can cause personal injury.
Air in Cooling System
Allow the engine to cool, and remove the radiator cap.
L-1075