Power Plant Assembly Removal - PREVOST H3-41 Maintenance Manual

2.4 POWER PLANT ASSEMBLY REMOVAL

To access the engine
components, the vehicle power plant assembly
must be removed as a whole unit by means of a
slide-out cradle. The power plant assembly
includes the engine, transmission (including
retarder if so equipped), air compressor,
alternator and transmission oil cooler.
Remove the power plant assembly as follows:
CAUTION
Tag hoses and cables for identification before
disconnecting in order to facilitate reinstallation.
Plug all openings to prevent dirt from entering
the system.
NOTE
No parts within the EECU are serviceable. If
found defective, replace the EECU as a unit.

First
1. Close the heater line shut-off valves.
2. Disconnect batteries from the starting
system by removing battery cables. With
the electrical circuit disrupted, accidental
contact with the starter button will not
produce an engine start.
WARNING
Due to the heavy load of the rear bumper
assembly, it must be adequately supported
before attempting to remove it.
3. Remove the rear
complete with hitch if applicable from the
vehicle. Refer to Section 18, BODY, under
"REAR BUMPER REMOVAL".
4. Using the quick-connect drain hose, drain
the engine cooling system. Refer to
Section 05, COOLING under "DRAINING
COOLING SYSTEM".
5. If applicable, disconnect the block heater
connector located near the EGR mixing
chamber.

With Vehicle Raised
or engine-related
bumper assembly
PA1621 Maintenance Manual All Series | January 2017
1. Using a vehicle lift or jack, raise vehicle to
access transmission fasteners and wire
harness.
2. From under the vehicle, disconnect the
propeller shaft as detailed in Section 09,
under heading "Propeller Shaft Removal".
3. Partially remove L.H. side transmission
protective panel to access connectors.
4. Disconnect transmission harness from
transmission housing.
5. On vehicles equipped with an automatic
transmission provided with a hydraulic
output retarder, disconnect steel-braided
airline from pressure regulator output. The
pressure regulator is mounted in the upper
section of engine compartment backwall
and is accessible through the engine
compartment R.H. side door.
6. Remove the retaining bolts, washers and
nuts securing the power plant cradle to the
vehicle rear subframe.
7. Disconnect the engine coolant hose near
the starter.
8. Disconnect air compressor suction and
discharge hoses.

With Vehicle Lowered
Lower the vehicle enough to access all
components.
 Engine Compartment R.H. side
1. If applicable, remove auxiliary sump tank to
ease access.
2. Purge the A/C system and disconnect the
A/C compressor hoses. Refer to Section
22, HEATING AND AIR CONDITIONING
under "CENTRAL AIR CONDITIONING".
3. Disconnect cables from chassis grounds.
4. Inside engine compartment, disconnect
starter, alternators and heater cables. Also
disconnect AFSS cable if applicable.
Disconnect from engine, connector C397 and
vehicle interface harness connector located
above EECU connectors. Also disconnect DPF
cable.
5. Disconnect power steering pump hoses.
SECTION 01 : ENGINE
19