9. Install Air Compressor Belt. Refer to Air
Compressor Belt Replacement.
10. Install Main Accessory Drive Belt.
Refer to OEM service manual for
procedure and routing.
11. Fill cooling system. Follow OEM
specifications.
12. Verify proper operation.
13. Run engine to operating temperature
and inspect for leaks.
14. Clean any excess oil or coolant from
engine.

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Air Conditioning (A/C) Compressor Removal
(in conjunction with Upper and Lower Intake Manifold Removal)

REMOVAL PROCEDURE

2

If vehicle is equipped with single or dual
A/C compressors the A/C system does not
need to be discharged when removing the
Upper and/or Lower Intake manifold.
Refer to Upper Intake Manifold and Lower
Intake Manifold Replacement Procedure.
1. Secure vehicle.
2. Disconnect battery ground cable.
3. Remove Drive Belt (3) from A/C
compressor(s). Figure 1
Refer to OEM Drive Belt Replacement
Procedure.
4. Disconnect electrical wire connectors
at back of A/C compressor.
5. Remove QTY: 4 A/C compressor
mounting bolts (1) per compressor (2).
Figure 1.
6. Remove A/C compressor(s) (2). Figure
1
7. Lift A/C compressors (2) and hoses
over to top of intake manifold and
place on driver side inner fender well.
Figure 2

2
3

1
Figure 1

A/C compressor mounting bolts (1), Compressor (2),
Drive Belt (3). NOTE: Dual A/C configuration shown;
single A/C configuration similar

Use wire to temporarily secure A/C
compressors out of work area.

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INSTALLATION PROCEDURE
1. Lift A/C compressor(s) and hose
assemblies over top of Upper Intake
Manifold. Figure 2
2. Position A/C compressor(s) into
mount(s).
3. Install QTY:4 mounting bolts for each
A/C compressor and tighten to spec.
Figure 1
4. Connect electrical wire connectors.
Apply dielectric grease to
connectors.
5. Reinstall drive belt. Figure 1. Refer to
OEM Drive Belt Replacement
Procedure.
6. Verify proper operation.

4

2

Figure 2
A/C lines (4) in place prior to A/C compressor (2)
removal. Once A/C compressor(s) is/are removed
from engine, compressor and hose assembly may be
flipped over top of engine and placed on driver side of
engine compartment.

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Air Intake Tube Replacement
REMOVAL PROCEDURE
1. Secure vehicle.
2. Disconnect Mass Air Flow (MAF)
Sensor Electrical Connector (1). Figure
1
3. Remove (2) Nylon Push Pins—aka
“Christmas Tree Pins”—(not shown)
securing Engine Harness to Air Intake
Tube Bosses (9). Figure 2
4. Loosen Worm Clamp Collar (4) at
Air Filter Housing Elbow.
Air Cleaner (not shown) varies
with OEM.
5. Loosen Worm Clamp Collar (2) at
Throttle Body (6). Figure 1
6. Disconnect Makeup Air Tube at
location (7) from Air Intake Tube
(3). Figure 2
7. Using a twisting motion, walk Air
Intake Tube (3) off Throttle Body
(6)
Figure 1.

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2

3

5
1
4

Figure 1:
Partial Air Intake Assembly: MAF Sensor (1),
Worm Clamp Collars (2 and 4), Air Intake Tube (3),
Throttle Body (6), Flow Direction Arrow (5)

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INSTALLATION PROCEDURE
1. If removed: Inspect Mass Air Flow
(MAF) Sensor (8) O-Ring for wear.
Figure 1

7
2

Replace MAF Sensor O-Ring if
damaged.
2. If removed: Install MAF Sensor (8)
Figure 2. Refer to Mass Air Flow
Sensor Replacement.
3. Install Air Intake Tube (3) on Air
Filter Housing Elbow (not shown).
To ease installation, apply a light
coat of soapy water to rubber
grommets on Air Intake Tube ends.
4. Install other end of Air Intake Tube (3)
on Throttle Body (6).

3

4

9

8

Figure 2.
Air Intake Tube (3), Air Make Up Tube location (7),
MAF Sensor (8), Worm Clamp Collars (2 & 4),
Engine Harness Pin Bosses (9)

Verify Flow Arrow (5) points at
Throttle Body (6). Figure 1
5. Verify Air Intake Tube (3) is centered
on both ends and MAF Sensor (8) is
perpendicular to Air Intake Tube.
Figure 2
6. Make sure the Worm Clamp Collars
are pushed all the way on to the
throttle body, tighten Worm Clamp
Collar (2) and (4). Figures 1 & 2
7. Connect MAF Sensor Electrical
Connector (1). Figure 1
8. Secure Engine Harness by installing
(2) Nylon Push Pins—aka “Christmas
Tree Pins”—(not shown) into Air Intake
Tube Bosses (9). Figure 2
9. Install Makeup Air Tube at location (7)
on Air Intake Tube. Figure 2
10. Verify operation and check for air
leaks.

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Alternator Removal

Hexagon Agility does not supply the alternator for the 488LPI™ propane autogas engine but
provides this instruction as a courtesy because alternator removal may be required for certain
service procedures. Obtain alternator diagnostics and parts from vehicle OEM.
REMOVAL PROCEDURE
1. Secure vehicle.
2. Disconnect battery (‒) ground cable.
3. Remove drive belt. Refer to OEM Drive Belt
Replacement Procedure.
4. Disconnect electrical wire connectors (not
visible) at back of Alternator.
5. Remove four (4) Bolts (2) securing Alternator
(1). Figure 1
6. Remove Alternator (1). Figure 1

2

1

3

INSTALLATION PROCEDURE
1. Position Alternator (1) in mounting saddle (3)
on Front End Accessory Drive bracket (4).
Figure 1
2. Secure Alternator (1) to Front End Accessory
Drive bracket (4) using four Bolts (2). Figure 1
Tighten bolts to 55 Nm (41 ft-lbs).
3. Connect electrical wire connectors.

4
Figure1:
Alternator (1), Bolts (2), Saddle (3),
Front End Accessory Drive bracket (4)

Apply dielectric grease to connectors.
4. Reinstall drive belt. Refer to OEM Drive Belt
Replacement Procedure.
5. Reconnect battery (‒) ground cable.
6. Verify proper operation.

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Belt Tensioner Replacement
1

REMOVAL PROCEDURE
1. Verify vehicle is secured properly.
Ensure engine is off and cool.
2. Insert a 1/2-in drive breaker bar into
square socket (1) on the appropriate
Belt Tensioner (3) or (6) to relieve
tension on the Main Accessory Drive
Belt (not shown). Figure 1, 2, or 3
3. Remove Main Accessory Drive Belt.
4. Remove Belt Tensioner Retaining Bolt
(not shown).
5. Remove Belt Tensioner (3) or (6).
Figure 1, 2, or 3

3

2
Figure 1:
Belt Tensioner (3) location on Front End Accessory
Drive (FEAD) Bracket (2) and Drive Socket (1).
NOTE: Non-AC and Dual A/C equipped engines
4
3
1

Figure 2:
Belt Tensioner (3) location on Single A/C Bracket (4)
and Drive Socket (1).
NOTE: Single A/C equipped engines only.

5

1

6

Figure 3:
Dual A/C Belt Tensioner (6) on Dual A/C Bracket (5)
and Drive Socket location (1).
NOTE: Dual A/C equipped engines only.

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INSTALLATION PROCEDURE
1. Position Belt Tensioner (3) or (6) on
appropriate Drive Bracket. Figure 1, 2,
or 3
2. Install Belt Tensioner Retaining Bolt
(not shown).
Tighten Belt Tensioner Retaining
Bolt (not shown). Refer to Engine
Front End Accessory Drive (FEAD)
Torque Specifications.
3. Route and install Main Accessory Drive
Belt. Refer to OEM service manual for
procedure and routing.
4. Verify proper operation.

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Block Heater Replacement
REMOVAL PROCEDURE
1. Secure vehicle.
2. Verify engine is off and has had ample
time to cool before attempting
procedure.
3. Drain coolant from Radiator. Follow
OEM procedure.
1

Reuse or properly dispose of
coolant.
4. Loosen Block Heater Expansion Bolt.
Do not remove Bolt.
5. Remove Block Heater (2) from location
(1) on engine. Figure 2

Figure 1:
Factory installed Block Heater location (1)

Prepare to collect coolant. Reuse or
properly dispose of coolant.
INSTALLATION PROCEDURE
1. Clean gasket surface in engine block
at Block Heater location (1). Figures 1
and 2
2. Install new Block Heater (2) in engine
at location (1). Figure 2
3. Tighten Block Heater Expansion Bolt.
Refer to Engine Mechanical Torque
and Clearance Specifications.
4. Fill engine coolant. Follow OEM
procedure.
5. Clean any spilled fluids.
6. Verify proper operation.

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2

Figure 2:
Block Heater (2) and Block Heater location (1)

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Camshaft Inspection and Replacement Procedure
Camshaft Lobe wear may be identified by measuring valve lift. A spun Camshaft Bearing may
restrict oil flow to the valvetrain and other critical engine components. Premature Camshaft
Bearing or Lobe wear may cause low or sporadic engine vacuum readings resulting in stored
ECM fault codes. Use the procedures outlined below for Camshaft inspection and verification of
Camshaft failure. If the Camshaft Lobes or Camshaft Bearings are deemed defective or worn, the
engine must be taken out of service.
CAMSHAFT LOBE INSPECTION PROCEDURE (Indirect - via valve lifter wear)
1.
2.
3.
4.
5.
6.
7.

Secure vehicle and verify engine is cool.
Remove Upper Intake Manifold. Refer to Upper Intake Manifold Replacement.
Remove Lower Intake Manifold. Refer to Lower Intake Manifold Replacement.
Remove Valley Pan. Refer to Valley Pan Replacement.
Remove Valve Covers. Refer to Valve Cover Replacement.
Loosen Valve Rocker Arms. Refer to Valve Rocker Arm Replacement.
Remove and Inspect Pushrods. Refer to Pushrod Inspection and Replacement.
Clean lifters in parts washer solvent.

Intake and Exhaust Pushrods are different lengths. Pushrods must be kept in
order of removal. If abnormal Pushrod wear is evident or Pushrod oil passages
are clogged, inspect for Camshaft and other valvetrain damage.
8. Remove Valve Lifters from block. Refer to Valve Lifter Replacement.
Clean Valve Lifters in parts washer solvent and organize Valve Lifters in order of
removal.
9. Visually inspect each Valve Lifter for signs of wear, scoring, or metal shavings.
If abnormal Valve Lifter wear is evident, Camshaft Lobe wear is likely.
Document all findings in detail to support Engine Warranty Repair/
Replacement requirements and authorization.
10. Proceed to Camshaft Removal / Camshaft Lobe, Journal and Bearing Inspection
Procedure (below).

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CAMSHAFT REMOVAL / CAMSHAFT LOBE,
JOURNAL AND BEARING INSPECTION PROCEDURE (Direct - visual & quantitative)
1. Follow Steps 1-9 of Camshaft Lobe
Inspection Procedure (above).
2. Remove Cooling Pack. Follow OEM
procedure.
3. Remove Main Accessory Drive Belt.
Follow OEM procedure.
4. If equipped: Remove Air Compressor
Belt. Refer to Air Compressor Belt
Replacement.
5. Remove Water Pump. Refer to Water
Pump Replacement.
6. Remove Harmonic Damper. Refer to
Harmonic Damper Replacement.
7. Remove Engine Front Cover. Refer to
Engine Front Cover Replacement.
8. Remove Timing Chain and Sprockets.
Refer to Timing Chain and Sprocket
Replacement.
9. Remove two (2) Camshaft Retaining
Bolts (1) and Camshaft Retainer (2).
Figure 1
10. Install three (3) 8-1.25 x 100mm Bolts (3)
in Camshaft front snout (4). Figure 2
11. Using three (3) 8-1.25 x 100mm Bolts as
a handle, carefully remove Camshaft
while slowly rotating it back and forth and
remove Bolts. Figure 2

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2
Figure 1:
Camshaft Retainer (2) and
Camshaft Retainer Bolts (1)

4

3

5

Figure 2:
Install three (3) 8-1.25 x 100mm Bolts (3)
in Camshaft front snout (4);
use as handle to remove Camshaft (5)

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12. Inspect Camshaft Lobes (6) for signs of
damage. Figures 3 & 4

7

8

6
Normal Camshaft Lobes show an even
wear pattern: wide at the Lobe Nose and
narrowing back to the Lobe Heel.
Abnormal Cam Lobes exhibiting wide
wear across entire lobe surface require
Camshaft replacement; follow Warranty
Authorization procedure before proceeding.
13. Inspect Cam Bearing Journals (9) for signs
of damage. Figures 3 & 5
Before reusing Camshaft, verify all
Camshaft Journals are same diameter
with a Micrometer (10) as shown in Figure
5. If not, Camshaft Bearing damage may
occur.
14. Use inspection mirror and flashlight to
inspect Camshaft Bearings (11) for visual
evidence of excessive wear*, galling, pitting,
scoring, or embedded debris.
*Measure Camshaft Bearing inside
diameter (ID) using a Micrometer to
verify an oversize condition. Figure 6

9

3
Figure 3:
Camshaft (3) with abnormal Camshaft Journal
showing scoring / excessive wear (7), abnormal
Camshaft Lobe exhibiting scoring / excessive wear (8),
normal Camshaft Lobe (6),
normal Camshaft Journal (9)

Nose

Lobe
Lift

Base
Circle

Heel
Figure 4:
Camshaft Lobe (6) Features

Bearing material with different shades of
gray is normal, and NOT evidence for
bearing replacement.
Verify no Camshaft Bearings have
spun out of position. This could cause
oil flow blockage.
15. If Camshaft Bearing damage or
misalignment is found, refer to Engine
Replacement procedure.

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488LPI Propane Autogas Engine Mechanical
and Fuel Components Service Manual