MBE 4000 – Section 1.13 Flywheel

Section 1.13
Flywheel

Three special tools are required for this procedure. They are:‪

• Engine Barring Tool (J–46392)
• 19 mm Flywheel and Main Pulley Socket (J–45390)
• Flywheel Guide Pins (set of 2) (J–46172)

The flywheel has a pilot bearing and spacer pressed into the flywheel hub bore. See Figure "Flywheel and Components" . ‪

1. Crankshaft‪	3. Spacer‪	5. Pilot Bearing‪
2. Crankshaft Gear‪	4. Flywheel‪

Figure 1. Flywheel and Components

Section 1.13.1
Flywheel Removal

Remove the flywheel as follows:‪

1. Remove the transmission.
2. Remove the clutch from the flywheel.
3. Remove the crankshaft position sensor from the flywheel housing. See Figure "Crank Angle Position Sensor Removal" .
   

   1. Crankshaft Position (CKP) Sensor‪

   2. Camshaft Position (CMP) Sensor‪

   Figure 2. Crank Angle Position Sensor Removal

4. Remove the inspection cover from the flywheel housing and install the engine barring tool (J–46392) . Insert the pin and make sure the tool is locked. Refer to "1.16.2 Engine Barring Tool Removal" .
5. Using the 19 mm socket (J–45390) , remove two flywheel socket-head bolts from the flywheel, one from each side of the bolt circle. See Figure "Flywheel (exploded view)" .
   

   1. Flywheel Mounting Bolt (10 qty.)‪

   2. Flywheel‪

   Figure 3. Flywheel (exploded view)

6. Screw the two flywheel guide pins (J-46172) into the empty bolt holes in the center of the flywheel. See Figure "Flywheel Removal" .
   

   1. Bolt used as a handle‪

   2. Flywheel Mounting Bolt‪

   Figure 4. Flywheel Removal

   FALLING FLYWHEEL ‪
   To avoid injury from a falling flywheel when removing the last bolt, hold the flywheel against the crankshaft by hand to prevent it from slipping off the crankshaft. The flywheel is not doweled to the crankshaft.‪

7. Remove the remaining eight flywheel bolts.
8. Remove the engine barring tool (J–46392) . Refer to "1.16.2 Engine Barring Tool Removal" .

   FALLING COMPONENT ‪
   To avoid injury from a falling component, ensure a proper lifting device is used.‪

9. Remove the flywheel, leaving the guide pins (J–46172) in place. See Figure "Flywheel Removal" .
   1. On opposite sides of the bolt circle, screw a bolt into each of two threaded clutch bolt holes.
   2. Using the two bolts as handles, dislodge the flywheel from the crankshaft flange and remove it from the flywheel housing.
   3. After removing the flywheel, remove the bolts from the clutch bolt holes.
10. Inspect the flywheel bolts. Replace the bolts if any of the shanks are stretched beyond the maximum length of 77.0 mm (3.03 in.). See Figure "Measuring the Flywheel Bolts" .
    

    1. Shank‪

    Figure 5. Measuring the Flywheel Bolts

11. Thoroughly clean the flywheel and check the clutch surface for cracks, burned spots, or scoring.

    If the damage exceeds the maximum depth of stock, replace the flywheel. Refer to "1.13.1.2 Flywheel Machining" .‪

12. Inspect the flywheel flange for signs of wear or traces of hollowing caused by the radial seal.
13. Inspect the flywheel ring gear for damaged teeth or signs of wear. Replace the ring gear if necessary. Refer to "1.14.1 Ring Gear Replacement" .

Section 1.13.1.1
Flywheel Inspection

Inspect the flywheel as follows:‪

1. Remove the flywheel. Refer to "1.13.1 Flywheel Removal" .
2. Thoroughly clean the flywheel and check it for cracks, scoring, burned areas, or rough spots.
3. Using an accurate straightedge and a feeler gauge, check the friction (clutch) surface for evenness. See Figure "Checking the Friction Surface for Evenness" . If the surface has areas that are too high or too low, replace the flywheel.
   

   1. Straightedge‪

   2. Friction Surface‪

   Figure 6. Checking the Friction Surface for Evenness

4. Check the bearing surface and the threaded holes for wear and damage.

Section 1.13.1.2
Flywheel Machining

Machine the flywheel as follows:‪

Note: Before beginning any machining work on the flywheel, check it to see if machining is possible. If the scores or cracks are deeper than 1 mm (0.04 in.), replace the flywheel. If the width of the flywheel between the friction surface and the mounting flange is less than 60 mm (2.4 in.), replace the flywheel.

PERSONAL INJURY ‪
To avoid injury while performing the test or procedure, wear adequate eye, face protection, and heat-resistant gloves.‪

1. Machine the flywheel friction surface, if required, to the specifications listed in Table "Flywheel Specifications" . See Figure "Machining the Flywheel Friction Surface" . The surface finish (peak-to-valley height) after machining should be 0.016 mm (0.0006 in.). A rougher surface finish will cause rapid clutch lining wear, while a smoother finish could cause difficulties in clutch disengagement. See Figure "Flywheel Cross Section" for the locations on the flywheel to coordinate with the specifications in the table.
   

   Figure 7. Machining the Flywheel Friction Surface

   Description ‪	Specification: mm (in.) ‪
   Flywheel Outside Diameter‪	486.60-487.40 (19.157-19.189)‪
   Flywheel Shoulder Diameter (for ring gear mounting)‪	432.450-432.645 (17.0256-17.0332)‪
   Flywheel Diameter at Crankshaft Flange‪	114.980-115.015 (4.5268-4.5281)‪
   Flywheel Diameter for Mounting Clutch‪	475.000-475.063 (18.7008-18.7032)‪
   Flywheel Minimum Width Between Friction Surface and Mounting Flange After Machining‪	60 (2.4)‪
   Flywheel Maximum Overall Width‪	70 (2.8)‪
   Peak-to-Valley Height (R z ) of Clutch Friction Surface‪	0.016 (0.0006)‪
   Flywheel Permissible Deviation From True (radial and lateral)‪	0.2 (0.008)‪

   Table 10. Flywheel Specifications
   

   1. Flywheel‪

   2. Ring Gear‪

   Figure 8. Flywheel Cross Section

   After machining, the friction surface must not have any cavities or chatter marks.‪

2. Check the radial and lateral deviation from true of the flywheel. The deviation from true must not exceed 0.2 mm (0.008 in.).
3. Install the flywheel. Refer to "1.13.2 Flywheel Installation" .

Section 1.13.2
Flywheel Installation

Install the flywheel as follows:‪

NOTICE:
Ensure that the spacer ring is installed in the flywheel to prior to installing the flywheel on the crankshaft. Failure to install the spacer ring will result in improper operation of the transmission. ‪

FALLING COMPONENT ‪
To avoid injury from a falling component ensure, a proper lifting device is used.‪

1. Ensure that the spacer ring is installed in the flywheel to prior to installing the flywheel on the crankshaft.
   

   1. Pilot Bearing‪

   2. Spacer Ring‪

   3. Flywheel‪

   Figure 9. Pilot Bearing and Spacer Ring

2. Using a suitable lifting device install the flywheel over the guide pins (J–46172) . Align the dowel on the crankshaft with the guide hole in the flywheel (arrow). See Figure "Flywheel Alignment Mark" .
3. Install the engine barring tool (J–46392) in the flywheel housing and secure with two bolts. Insert the pin and make sure the tool is locked. Refer to "1.16.2 Engine Barring Tool Removal" .
   

   Figure 10. Flywheel Alignment Mark

   Note: Verify the alignment of the crankshaft dowel with the guide hole in the flywheel.

4. With a light coating of engine oil, lubricate the threads of the ten multipoint socket-head flywheel bolts.
5. Tighten the eight bolts in two stages. In each stage, use an alternate sequence to tighten the bolts, as listed in Table "Tightening Stages, Flywheel Mounting Bolts" .

   Max. Shaft Length, mm (in.) ‪	Tightening Stage ‪	Torque Value, N·m (lb·ft) ‪
   77.0 (3.03)‪	Stage 1‪	200 (147.5)‪
   77.0 (3.03)‪	Stage 2‪	90 degrees‪

   Table 15. Tightening Stages, Flywheel Mounting Bolts
   1. Install eight bolts to hold the flywheel in position.
   2. Remove the two guide pins (J–46172 ) and install the two remaining bolts in their place.
   3. Tighten the bolts, in an alternate tightening sequence, 200 N·m (147.5 lb·ft).
   4. Using the same tightening sequence, turn the flywheel bolts 90 degrees.
6. Remove the engine barring tool (J–46392) . Refer to "1.16.2 Engine Barring Tool Removal" .
7. If removed, install the pilot bearing and spacer in the flywheel. Refer to "1.15.2 Pilot Bearing Installation" .
8. Install the crank angle position sensor into the flywheel housing.
9. Install the clutch and the transmission.