JLG 534D-10 - Manual (Page 115)

7.7 534D-9, 534D-10 & 544D
Engine
7.5 ENGINE SERIAL NUMBER
The Cummins QSB4.5 serial number is stamped on a
plate which is typically located on the engine rocker
cover, but may be located on the side of the gear housing.
Information contained in the serial number is required in
correspondence with the engine manufacturer.
7.6 SPECIFICATIONS AND
MAINTENANCE INFORMATION
For engine, coolant and oil specifications, and
maintenance information, refer to Section 2, “General
Information and Specifications.”
Note: Detailed Cummins engine service instructions
(covering disassembly, inspection, internal repair,
assembly, adjustment and troubleshooting information)
are provided in the appropriate Cummins engine service
manual.
7.7 COOLING SYSTEM
7.7.1 Radiator Pressure Cap
For a 210° F (99° C) system, use a 13 psi (90 kPa)
radiator cap. An incorrect or malfunctioning cap can
result in the loss of coolant and a hot-running engine.
7.7.2 Thermostat Replacement
John Deere Engine
Before considering thermostat replacement, check the
coolant level, fan belt tension and instrument cluster
temperature indicator.
• If the engine seems to take a long time to warm
up, the thermostat may be stuck in the open posi-
tion and requires replacement.
• If the engine runs hot, check the temperature of
the upper radiator hose.
• If the hose is not hot, the thermostat may be
stuck in the closed position.
• If the engine has overheated, performance may
suffer, indicating other damage including a leak-
ing cylinder head gasket, cracked cylinder head
or block, and/or other internal engine damage.
Cummins Engine
The Cummins engine thermostat is not a serviceable
item. For more information, contact your local authorized
service distributor.
a. Thermostat Removal (John Deere)
1. Park the machine on a firm, level surface, level the
machine, fully retract the boom, lower the boom,
place the travel select lever in the (N) NEUTRAL
position, engage the parking brake, and shut the
engine OFF.
2. Place a Do Not Operate Tag on both the ignition key
switch and steering wheel, stating that the machine
should not be operated.
3. Open the engine cover. Allow the system fluids to
cool.
4. Remove the battery negative (-) cable from the
battery negative (-) terminal.
5. Slowly turn the radiator cap to the first stop and allow
any pressure to escape. Remove the radiator cap.
6. Place a funnel at the base of the radiator to channel
the drained coolant into the container. Loosen the
drain plug and slowly remove to allow the coolant to
drain. Transfer the coolant into a properly labeled
container. Dispose of properly if coolant needs to be
replaced. Replace the radiator drain plug.
7. Disconnect the Engine Water Temperature Sender.
8. Remove the capscrews securing the thermostat
housing (1) to the engine.
9. Remove the thermostat housing, old gasket and
thermostat. Clean all gasket surfaces. DO NOT let
any debris into the thermostat opening.
b. Thermostat Installation
1. Install the engine thermostat, thermostat gasket and
thermostat housing. Secure with the two capscrews.
2. Connect the Engine Water Temperature sender.
3. Connect the battery negative (-) cable to the battery
negative (-) terminal.
4. Open the radiator cap, and fill the radiator
completely with a 50/50 mixture of ethylene glycol
and water. Replace and tighten the radiator cap. Add
coolant to the overflow bottle until the bottle is 1/4 to
1/2 full. This overfilling will compensate for any air
trapped in the cooling system.
NOTICE
ALWAYS use the correct thermostat and install a new
gasket. NEVER operate the engine without a
thermostat, or engine damage will result.