12. Verify proper operation.
9.

13. Clean any excess fluids from engine.

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and Fuel Components Service Manual

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Single Air Conditioning (A/C) Drive
Bracket Replacement
REMOVAL PROCEDURE

2

1. Secure vehicle.
3
2. Verify engine is off and is cool.
1
3. Remove main accessory drive Belt
Tensioner (3) from Single A/C Bracket (2).
Figure 1. Refer to Belt Tensioner
Replacement.
4. Remove A/C Compressor (not shown)
from location (4) on Single A/C Bracket
Figure 1:
(2). Figure 2. Follow OEM procedure.
Belt Tensioner (3) location on Single A/C Bracket (2)
5. Remove three (3) Single A/C Bracket
and ½” Drive Socket (1).
Retaining Bolts (5) and Washers (6).
Figure 2
6. Remove Single A/C Bracket (2) from
7
passenger side Cylinder Head (7).
4
Figure 2
2

Bracket is heavy; please take
necessary precautions when removing.

6

5

Figure 2:
Single A/C Bracket (2), A/C Compressor location (4),
Bracket Retaining Bolts (5) and Washers (6),
passenger side Cylinder Head (7)

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and Fuel Components Service Manual

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INSTALLATION PROCEDURE
4

A/C Bracket is heavy; please take
necessary precautions when installing.
1. Thread one (1) Single A/C Bracket
Retaining Bolt (5) and Washer (6) through
Single A/C Bracket into passenger side
Cylinder Head (7). Figure 3.

2.
3.

4.
5.
6.

This helps distribute Bracket weight
and eases alignment.
Align Single A/C Bracket (2) mounting
holes with Cylinder Head (7) holes.
Figure 3
Install two (2) remaining Bolts (5) and
Washers (6) and torque all (3) Bolts (5).
Refer to Front End Accessory Drive
Torque Specifications. Figure 2
Install A/C Compressor (not shown) on
Single A/C Bracket (2) at location (4).
Follow OEM procedure. Figure 2
Install main accessory drive Belt
Tensioner. Refer to Belt Tensioner
Replacement.
Verify proper operation.

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6

5
7

Figure 3:
Install and thread one (1) Single A/C Bracket Bolt (5) and
Washer (6) to hold and align Single A/C Bracket (2) to
Cylinder Head (7) before installing and tightening
remaining two (2) Bolts (5) and Washers (6).

488LPI Propane Autogas Engine Mechanical
and Fuel Components Service Manual

Page 96 of 117

Thermostat Replacement
Do not attempt to replace thermostat while the engine is hot, let engine cool down before
changing thermostat to prevent being burned from hot coolant.
2

REMOVAL PROCEDURE
1. Drain Radiator coolant sufficiently below
the Thermostat Housing. Follow OEM
procedure.
2. Remove Upper Radiator Hose from its
attachment point (2) on Thermostat
Housing (4). Figure 1
3. Remove four (4) Thermostat Housing
Bolts (1). Figure 1
4. Remove Thermostat Housing (4).
Figures 1 & 2
5. Remove Thermostat(s) (3) from Lower
Intake Manifold (5). Figure 2
CLEANING AND INSPECTION

1

4

Figure 1:
Thermostat Housing (4),
Upper Radiator Hose attachment location (2),
Thermostat Housing Bolts (1)

While the thermostat housing is off the engine,
check all the following:
 Check for cracks or corrosion in
housing, replace if necessary.
 Clean old gasket material from
housing.
 Clean old gasket material from
Intake Manifold mating surfaces.
 Check Radiator hose and clamp
and replace if necessary.

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and Fuel Components Service Manual

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INSTALLATION PROCEDURE
1. Clean sealing surfaces on Thermostat
Housing and Lower Intake Manifold.
2. Lubricate new Thermostat O-rings with a
light coat of clean engine oil.
3. Install Thermostat(s) (3) in Lower Intake
Manifold (5). Figure 2
4. Install Thermostat Housing (4). Figure 2
5. Install Thermostat Housing Bolts (1).
Figure 1. Refer to Engine Mechanical
Torque and Clearance Specifications.
6. Fill engine coolant. Follow OEM
instructions. Refer to 488LPI™
Operators Manual for coolant
specifications.
7. Clean any spilled fluids from engine.
8. Bring engine up to operating temperature
and check for any coolant leaks.

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5
4

Figure 2:
Thermostat Housing (4),
Dual Thermostats (3),
Lower Intake Manifold (5)

488LPI Propane Autogas Engine Mechanical
and Fuel Components Service Manual

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Throttle Body Replacement
REMOVAL PROCEDURE

Handle Throttle Body components with care.
Do not immerse Electronic Throttle Body in
cleaning solvent of any kind.

1

Throttle Body Gasket should be replaced
when removing the Throttle Body.

2

1. Remove Air Intake Tube (not shown).
Refer to Air Intake Tube Replacement.
2. Disconnect Throttle Body Electrical
Connector (4). Figure 1
3. Remove four (4) Throttle Body Retaining
Bolts (3). Figure 1
4. Remove Throttle Body (2). Figure 1
5. Remove Throttle Body Gasket (1) and
discard. Figure 1

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3
Figure 1:
Throttle Body (2), Gasket (1),
Retaining Bolts (3),
Electrical Connector (4)

488LPI Propane Autogas Engine Mechanical
and Fuel Components Service Manual

Page 99 of 117

INSTALLATION PROCEDURE
1. Clean Upper Intake Manifold and
Throttle Body to Upper Intake mating
surfaces with Throttle Body Cleaner.
2. Install two (2) Throttle Body Retaining
Bolts (3) into Throttle Body (1). Figure 1
3. Install new Throttle Body Gasket (2)
over the Throttle Body Retaining Bolts
(3). Figure 1
4. While holding the (2) Throttle Body
Bolts in place install Throttle Body and
Gasket on Upper Intake Manifold and
start the two (2) pre-installed bolts.
Figure 1
5. Install remaining two (2) Throttle Body
Bolts (3) and tighten all bolts in a
crosshatch pattern. Hand tighten the (4)
Throttle Body Bolts, then use a torque
wrench to obtain proper torque. Refer to
Engine Sensors and Electrical
Components Torque Specifications.
Figure 1.
Verify electric connector to
Throttle Body connector seals
are properly installed and not
damaged.
Apply dielectric grease to
connectors.
6. Connect Throttle Body Electrical
Connector (4). Figure 1
7. Install Air Intake Tube. Refer to Air
Intake Tube Replacement.
8. Verify proper operation.

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and Fuel Components Service Manual

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Timing Chain and Sprocket Replacement
REMOVAL PROCEDURE
1. Remove Cooling Pack. Follow OEM
procedure.
2. Remove Accessory Belt. Follow OEM
procedure.
3. If equipped: Remove Air Compressor
Belt. Refer to Air Compressor Belt
Replacement.
4. Remove Water Pump. Refer to Water
Pump Replacement.
5. Remove Harmonic Damper. Refer to
Harmonic Damper Replacement.
6. Remove Timing Chain Cover. Refer to
Timing Chain Cover Replacement.
7. Remove Valve Covers and loosen Roller
Rockers. Refer to Valve Cover
Replacement and Roller Rocker Arm
Replacement procedures.
8. Align Camshaft Sprocket timing mark (1)
and Crankshaft Sprocket timing mark (2)
by rotating Crankshaft. Figure 1
 Temporarily reinstall Harmonic
Damper Flanged Bolt (3) to rotate
engine using a breaker bar.
Figure 2
 Removing Spark Plugs may ease
this process.
 It may require up to two engine
rotations to align the marks

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1

Figure 1:
Camshaft Sprocket timing mark (1) and
Crankshaft Sprocket timing mark (2)

3

488LPI Propane Autogas Engine Mechanical
and Fuel Components Service Manual

Figure 2:
Harmonic Damper Flanged Bolt (3)

Page 101 of 117

9. Remove three (3) Camshaft Sprocket
Retaining Bolts (4). Figure 3
10. Remove Camshaft Sprocket (5) and
Timing Chain (6). Figure 3
11. If necessary: Remove Crankshaft
Sprocket (9) using special tool J 42846
(7) and a Three Jaw Puller (8). Figure 4

6

INSTALLATION PROCEDURE
1. Use special tool J 22102 to drive
Crankshaft Sprocket (9) on Crankshaft.
Verify Crankshaft Keyway is aligned with
Crankshaft Sprocket.

2. Remove special tool J 22102.
3. Rotate Crankshaft Sprocket alignment
mark (2) to 12 o’clock position. Figure 1
4. Install Camshaft Sprocket and Timing
Chain. Figures 1 and 3

4
2

5

Figure 3:
Camshaft Sprocket (5), Sprocket Retaining Bolts (4),
Timing Chain (6)

 Verify Camshaft Sprocket timing mark
(2) is at 6 o’clock position.
 Verify Timing Chain meshes with
Camshaft Sprocket teeth.
 Do not use a hammer to install
Camshaft Sprocket on Camshaft.

5. Once installed, verify timing marks are
aligned as follows:
 Crankshaft Sprocket mark (2) at 12
o’clock
 Camshaft Sprocket (1) at 6 o’clock
Figure 1

8

7

9

Figure 4:
Remove Crankshaft Sprocket (9)
using special tool J 42846 (7) and
Three Jaw Puller (8)

6. Install (3) Camshaft Sprocket Bolts.
Figure 3. Refer to Engine Mechanical
Torque and Clearance Specifications.
7. Install, tighten and adjust Roller Rocker
Arms. Refer to Roller Rocker Arm
Replacement.
8. Install Valve Covers. Refer to Valve
Cover Replacement.
9. Install Engine Front Cover. Refer to
Engine Front Cover Replacement.

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and Fuel Components Service Manual

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10. Install Harmonic Damper. Refer to
Harmonic Damper Replacement.
11. Install Water Pump. Refer to Water
Pump Replacement.
12. If equipped: Install Air Compressor Belt.
Refer to Air Compressor Belt
Replacement.
13. Install Main Accessory Belt. Follow OEM
procedure.
14. Install Cooling Pack. Follow OEM
procedure.
15. Fill engine fluids.
16. Start vehicle and bring up to temperature
and check for leaks.

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and Fuel Components Service Manual

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Upper Intake Manifold Replacement
REMOVAL PROCEDURE

If removing, Lower Intake Manifold, fuel
must be drained from the fuel lines prior to
bringing vehicle into shop. Refer to LPG
Fuel Line Drain Procedure.
If removing Lower Intake, remove air filter
housing bracket (along with filter housing
and hose) from firewall by removing four
T40 Torx bolts.
If the vehicle is equipped with single or
dual A/C compressors Refer to A/C
Compressor Removal Procedure.
1. Secure vehicle.
2. Disconnect vehicle battery.
3. Remove alternator. Refer to Alternator
Removal Procedure.
4. Remove Air Cleaner Assembly (not
shown). Follow OEM procedure.
5. Remove Air Intake Tube (2). Figure 1.
Refer to Air Intake Tube Replacement.
6. Disconnect Engine Control Module
(ECM) (3) Electrical Connectors.
7. Remove ECM Retaining Bolts and
ECM (3).
8. Remove three bolts securing cab
heater shut off valve and move valve
down below throttle body, (this allows
room to remove TSM bolts.)
9. Disconnect TSM (4) Electrical
Connector.
10. Remove TSM (4) Retaining Bolts.
11. Remove TSM (4) and TSM Mounting
Bracket.

3

7

5

1

4

6

FRONT
10

8

2

9

Figure 2:
Upper Intake Manifold (1) Mounted Components:
Air Intake Tube (2), ECM (3), TSM (4),
MAP/TIAP Sensor (5), Makeup Air Tube (6),
Purge Solenoid Hose (7), Purge Solenoid (8),
Throttle Body Connector (9), Throttle Body (10)

1
FRONT
11
12

Figure 1: Upper Intake Manifold (1) with Upper Manifold
Retaining Bolts (11) and Lower Intake Manifold (12).
NOTE: Nuts not shown.

Handle ECM and TCM carefully.
Store in a safe location and do not
expose to solvents or cleaners.

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and Fuel Components Service Manual

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12. Disconnect MAP/TIAP Sensor (5)
Connector.
13. Remove MAP/TIAP Sensor (5). Refer
to MAP/TIAP Sensor Replacement.
14. Disconnect Makeup Air Tube from rear
of Upper Intake Manifold (6).
15. Disconnect Purge Solenoid (7)
Electrical Connector.
16. Disconnect Purge Solenoid Hose from
Upper Intake Manifold at location (7).
17. Remove Purge Solenoid (8).
18. Disconnect Throttle Body Electrical
Connector at location (9).
19. Remove Throttle Body (10). Refer to
Throttle Body Replacement.
20. Remove thirteen (13) Upper Intake
Manifold Retaining Bolts (11) and Nuts.
Figure 2
21. Remove Upper Intake Manifold (1)
from engine and discard Upper Intake
Manifold Gaskets (not shown). Figure
2
22.
23. Install four (4) Lower Intake Port
Covers, on Lower Intake Manifold
(12) to prevent debris falling into
Lower Intake. Figure 2
24. Inspect Upper and Lower Intake
Manifold sealing surfaces for damage.

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and Fuel Components Service Manual

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INSTALLATION PROCEDURE
1. Remove four (4) Lower Intake Port
Covers from Lower Intake Manifold.
2. Install new Upper Intake Manifold
Gaskets into grooves (not shown) on
Lower Intake Manifold.
3. Place Upper Intake Manifold (1) on