Timing Belt: Service and Repair
Fig. 53 Timing Belt Assembly (Part 1 Of 2):
Fig. 53 Timing Belt Assembly (Part 2 Of 2):
REMOVAL
Remove timing belt in numbered sequence as shown in Fig. 53, noting the following:
1. To remove engine mount bracket, slightly raise and support engine, removing weight of engine from mount.
2. Before removing alternator drive belt, loosen water pump pulley mounting bolts.
3. Remove auto tensioner as follows:
Timing Marks:
a. Turn crankshaft clockwise and align timing marks as shown.
Fig. 41 Auto Tensioner Assembly:
b. Remove auto tensioner. Do not loosen, remove or tighten the tensioner pivot bolt, Fig.41. If this bolt is disturbed, entire pivot bracket assembly must be replaced.
4. Prior to removal, mark timing belt to indicate direction of rotation for assembly reference.
5. To remove camshaft sprockets, proceed as follows:
a. While holding camshaft in position with a crescent wrench at hexagon between No. 2 and No. 3 journals, remove camshaft sprocket bolt.
b. Remove camshaft sprockets.
Fig. 36 Blocking Silent Shaft For Oil Pump Sprocket Removal:
6. Remove oil pump sprocket as follows:
a. Remove plug on side of cylinder block, then insert Phillips screwdriver into hole to block left silent shaft, Fig. 36.
b. Remove oil pump sprocket nut, then the sprocket.
INSPECTION
1. Inspect timing belts and replace if any of the following conditions exist:
a. Hardened or cracked back surface.
b. Cracked or separated canvas.
c. Cracked tooth bottom.
d. Cracked side.
e. Abnormal wear.
f. Missing teeth.
2. Inspect tensioner pulley and idler pulley. Replace pulleys if binding, excessive play, abnormal noise or grease leakage occurs while turning.
Fig. 55 Measuring Auto Tensioner Rod Protrusion. 2.0L/4-122:
3. Inspect auto tensioner for weak tension, leakage and rod end wear or damage. Check rod protrusion, Fig.55. If protrusion exceeds 0.47 inch, replace auto tensioner.
INSTALLATION
Reverse removal procedure to install, noting the following:
Fig. 45 Installing Crankshaft Sprocket:
1. Install crankshaft sprocket B (36) as shown in Fig. 45.
2. When installing spacer (35), apply a thin coating of engine oil to outside of spacer, then install spacer with chamfered end facing oil seal. Failure to install chamfered end toward oil seal may result in oil leakage.
Fig. 56 Aligning Crankshaft Sprocket B And Silent Shaft Sprocket Timing Marks.:
3. Before installing timing belt B, ensure mark on crankshaft sprocket B and mark on silent shaft sprocket are aligned as shown in Fig. 56. Install belt and adjust tension as follows:
a. Temporarily install timing belt B tensioner with the flange toward the front of the engine and the center of the tensioner pulley to the left and above center of the attaching bolt.
b. While holding the tensioner in your hand, apply pressure on the timing belt until the tension side of the belt is taut, then tighten tensioner bolt.
c. To check tension, depress the tension side of the belt with your finger. Belt deflection should be 0.20-0.28 inch.
Fig. 47 Installing Crankshaft Sprocket Flange:
4. Install flange (31) and crankshaft sprocket (30) in direction as shown in Fig. 47.
Fig. 36 Blocking Silent Shaft For Oil Pump Sprocket Removal:
5. When installing oil pump sprocket, install a Phillips screwdriver into plug hole, Fig. 36, to block the left silent shaft, then install oil pump sprocket and attaching bolt.
6. To install camshaft sprockets, hold camshaft in position with a crescent wrench at hexagon between No. 2 and No. 3 journals, remove camshaft sprocket bolt, then install sprocket and attaching bolt.
7. When installing auto tensioner, if rod is in fully extended position, reset as follows:
a. Using a soft-jawed vise, clamp the auto tensioner in a level position. If plug protrudes from bottom of tensioner, place a flat washer around it to prevent damage from vise.
Fig. 57 Retracting Auto Tensioner Rod.:
b. Slowly close vise until set hole (A) in tensioner rod is aligned with set hole (B) in tensioner cylinder, Fig. 57.
c. Insert a piece of wire through the set holes, then install auto tensioner. Leave wire installed in tensioner.
Fig. 58 Installing Tensioner Pulley.:
8. Install the tensioner pulley with pinhole in pulley shaft to left of center bolt, Fig. 58. Hand tighten center bolt.
9. Install timing belt as follows:
Fig. 59 Aligning Exhaust & Intake Camshaft Sprocket Timing Marks.:
a. Turn camshaft sprockets so dowel pins are on top, then align timing marks so they face each other, parallel with the top surface of the cylinder head, Fig. 59.
Crankshaft Timing Mark:
Fig. 36 Blocking Silent Shaft For Oil Pump Sprocket Removal:
b. Align crankshaft sprocket timing mark, then the oil pump sprocket timing mark as shown. Ensure oil pump sprocket is installed correctly by removing plug in cylinder block, Fig. 36, then inserting a Phillips screwdriver into plug hole. Ensure screwdriver shaft can be inserted at least 2.4 inches. If screwdriver can only be inserted 0.80-1.00 inch, turn sprocket one rotation and realign timing marks. Reinsert screwdriver and leave it in the hole.
Fig. 61 Retaining Timing Belt To Intake Camshaft Sprocket.:
Fig. 62 Installing Timing Belt.:
c. Thread timing belt over intake-side camshaft sprocket and clip belt onto sprocket as shown, Fig. 61. Using two wrenches, feed timing belt over exhaust-side sprocket, Fig. 62, then clip belt onto exhaust-side sprocket.
d. Thread timing belt over idler pulley, oil pump pulley sprocket, crankshaft pulley sprocket and tensioner pulley, then remove clips.
e. Lift tensioner pulley toward top and center of engine, then tighten center bolt.
f. Ensure all timing marks are aligned, then remove screwdriver inserted into plug hole.
g. Turn crankshaft 1/4 turn counterclockwise, then turn clockwise until marks are realigned.
10. Adjust timing belt tension as follows:
Fig. 63 Adjusting Timing Belt Tension.:
a. It may be necessary to slightly raise and support engine to provide adequate body clearance during this step. Loosen auto tensioner center bolt and install auto tensioner installation tool No. MD998752 or equivalent and a torque wrench as shown in Fig. 63. Apply 22.2 - 24.6 in.-lbs. torque, then while holding tensioner pulley with installation tool, tighten center bolt.
Fig. 64 Installing Auto Tensioner Tool.:
b. Screw auto tensioner installation tool MD998738 or equivalent into left engine support bracket until it contacts tensioner arm, Fig. 64. Screw tool in slightly more, then remove piece of wire installed into auto tensioner. Remove installation tool.
Fig. 65 Checking Auto Tensioner Protrusion.:
c. Rotate crankshaft clockwise two complete turns, then let tensioner set for 15 minutes. After time has expired, measure distance between tensioner arm and tensioner body (A), Fig. 65. Clearance should be 0.15 - 0.18 inch. If clearance is not as specified, repeat steps 10A, 10B and 10C until clearance is within specifications.
d. If clearance does not exist between tensioner arm and body, reinstall installation tool MD998738 or equivalent, screwing tool in until it contacts tensioner arm. Once the tool contacts tensioner arm, screw in further (2.5 - 3.0 turns) until tensioner pushrod is moved back and tensioner arm contacts tensioner body. Remove installation tool.
e. Install rubber plug into timing belt rear cover.
11. When installing semi-circular packing, apply liberal amount of gasket sealant onto circumference of packing.
Fig. 23 Installing Rocker Cover.:
12. When installing rocker cover, apply gasket sealant to area as shown in Fig. 23.
Fig. 53 Timing Belt Cover Attaching Bolts:
Fig. 54 Timing Belt Cover Attaching Bolts:
13. Refer to Fig.53 and 54 when installing timing belt upper and lower cover attaching bolts.