Timing Belt: Service and Repair
TIMING BELT (16 VALVE) REMOVAL AND INSTALLATION
REMOVAL SERVICE POINTS
"A" ENGINE MOUNT BRACKET REMOVAL
1. Place a wooden block against the oil pan of the engine, and then jack up the vehicle.
CAUTION:
- Jack up carefully not to damage other parts.
2. Remove the engine mount bracket.
"B" AUTO TENSIONER REMOVAL
1. Turn the crankshaft clockwise and align the timing marks.
CAUTION:
- Never rotate the crankshaft counterclockwise.
2. Remove the auto tensioner.
"C" TIMING BELT REMOVAL
NOTE: Chalk an arrow mark indicating the rotation direction on the back of the timing belt for reassembly.
CAUTION:
- Do not let oil or water touch the removed parts.
- If the removed parts have already been contaminated, check the front case oil seals, camshaft oil seal and water pump for leaks.
"D" CAMSHAFT SPROCKET REMOVAL
1. Rotate the crankshaft clockwise and align the timing mark.
CAUTION:
- Never rotate the crankshaft counterclockwise.
2. Tie the camshaft sprocket and timing belt with a cord. Otherwise, ignition timing will be maladjusted.
3. Use the special tool to remove the camshaft sprocket.
CAUTION:
- Never rotate the crankshaft after removing the camshaft sprocket.
"E" OIL PUMP SPROCKET REMOVAL
1. Remove the plug on the side of the cylinder block.
2. Insert a Phillips screwdriver [shank diameter 8 mm (0.31 in.)] to block the left counterbalance shaft.
3. Remove the oil pump sprocket nut.
4. Remove the oil pump sprocket.
"F" TIMING BELT "B" REMOVAL
NOTE: Chalk an arrow mark indicating the rotation direction on the back of the timing belt for reassembly.
CAUTION:
- Do not let oil or water touch the removed parts.
- If the removed parts have already been contaminated, check the front case oil seals, camshaft oil seal and water pump for leaks.
INSPECTION
TIMING BELTS CHECK
NOTE: Should the following defects be evident, replace the belt.
(1) Hardened back surface rubber Glossy, non-elastic, and so hard that no mark is produced even when scratched by a fingernail.
(2) Cracked back surface rubber.
(3) Cracked or separated canvas.
(4) Cracked tooth bottom.
(5) Cracked side.
(6) Abnormal wear on side.
NOTE: Normal belt should have clear-cut sides as if cut by a sharp knife.
(7) Abnormal wear on teeth.
Initial stage: Canvas on load side tooth flank worn (Fluffy canvas fibers, rubber gone and color changed to white, and unclear canvas texture).
Final stage: Canvas on load side tooth flank worn down and rubber exposed (tooth width reduced).
(8) Missing tooth.
TENSIONER PULLEY AND IDLER PULLEY CHECK
1. Turn the pulleys to check for possible binding, excessive play, and unusual noise. Replace the pulley if any of these defects is evident.
2. Replace if there is a grease leak.
AUTO TENSIONER CHECK
1. Check the auto tensioner for possible leaks and replace as necessary.
2. Check the rod end for wear or damage and replace as necessary.
3. Measure the rod protrusion. If it is not within the standard value, replace the auto tensioner.
Standard value: 12 mm (0.47 in.)
4. Using a vise with soft jaws push in the auto tensioner rod. If the rod can be easily retracted, replace the auto tensioner. You should feel some resistance when pushing the rod in.
CAUTION:
- Clamp the auto tensioner in the vise so it maintains a level position.
CAUTION:
- If the plug at the bottom of the auto tensioner protrudes, surround it with a plain washer as illustrated to prevent the plug from touching with the vise (auto tensioner with plug).
INSTALLATION SERVICE POINTS
"A" ENGINE SUPPORT BRACKET INSTALLATION
NOTE: Apply sealant to the bolt shown in the figure and tighten it to the specified torque.
Specified sealant: MITSUBISHI GENUINE PART No. MD970389 or equivalent
"B" CRANKSHAFT SPROCKET "B" INSTALLATION
NOTE: Pay attention to its direction.
"C" SPACER INSTALLATION
1. Apply a thin coat of engine oil to the outer inside diameter of the spacer.
2. Install the spacer with the chamfered end facing the oil seal.
NOTE: If the spacer is installed adversely, the oil seal may be damaged, resulting in the oil leaks.
"D" TIMING BELT "B" INSTALLATION
1. Align the crankshaft sprocket "B" timing mark the counterbalance shaft sprocket timing mark.
2. Fit timing belt "B" over crankshaft sprocket "B" and the counterbalance shaft sprocket. There must be no slack in the belt.
"E" TIMING BELT "B" TENSION ADJUSTMENT
1. Temporarily fix the timing belt "B" tensioner so that the center of the tensioner pulley is to the left and above the center of the installation bolt, and temporarily attach the tensioner pulley so that the flange is toward the front of the engine.
2. Holding the timing belt "B" tensioner up with your finger in the direction of the arrow, place pressure on the timing belt so that the tension side of the belt is taut. Now tighten the bolt to fix the tensioner.
CAUTION:
- Do not let the tensioner pulley shaft rotate with the bolt, otherwise the belt will become too tight.
3. Depress the belt (point A) with a finger to check the tension. If it is not within the standard value, adjust it.
Standard value: 5 - 7 mm (0.20 - 0.28 in.)
"F" CRANKSHAFT SENSING BLADE / FLANGE INSTALLATION
CAUTION:
- Pay special attention to the direction of the crankshaft sensing blade or flange, otherwise the timing belt will be damaged.
"G" CRANKSHAFT SPROCKET INSTALLATION
CAUTION:
- Pay special attention to the direction of the flange, otherwise the timing belt will be damaged.
"H" AUTO TENSIONER INSTALLATION
1. If the auto tensioner rod is in its fully extended position, reset it as follows.
(1) Keep the auto tensioner level and clamp it in the vise with soft jaws. If the plug at the bottom of the auto tensioner protrudes, surround it with a plain washer as illustrated to prevent the plug from touching the vise (auto tensioner with plug).
(2) Push in the rod little by little with the vise until the set hole A in the rod is aligned with that B in the cylinder.
(3) Insert a wire 1.4 mm (0.055 in.) in diameter, into the set holes.
(4) Unclamp the auto tensioner from the vise.
2. Install the auto tensioner.
CAUTION:
- Do not take out the wire.
"I" TENSIONER PULLEY INSTALLATION
1. Install the tensioner pulley onto the tensioner arm.
2. Locate the pinhole in the tensioner pulley shaft to the left of the center bolt. Then, tighten the center bolt finger-tight.
CAUTION:
- Do not take out the wire.
"J" TIMING BELT INSTALLATION
1. Align the timing marks of the camshaft sprocket, the crankshaft sprocket, and the oil pump sprocket.
2. Remove the plug on the cylinder block and insert a Phillips screwdriver [shank diameter 8 mm (0.31 in.)] through the hole. If it can be inserted as deep as 60 mm (2.4 in.) or more, the timing marks are correctly aligned. If the inserted depth is only 20-25 mm (0.8 - 1.0 in.), turn the oil pump sprocket one turn and realign timing marks. Then check that the screwdriver can be inserted 60 mm (2.4 in) or more. Keep the screwdriver inserted until the installation of the timing belt is finished.
3. Install the timing belt around sprockets as follows.
(1) Install the timing belt around the tensioner pulley and crankshaft sprocket and secure the timing belt onto the tensioner pulley with your left hand.
(2) Pulling the belt with your right hand, install it around the oil pump sprocket.
(3) Install the belt around the idler pulley.
(4) Install it around the intake camshaft sprocket.
(5) Turn the exhaust camshaft sprocket one tooth clockwise to align its timing mark with the cylinder head top surface. Then, pulling the belt with both hands, install it around the exhaust camshaft sprocket.
(6) Gently raise the tensioner pulley as shown by the arrow, so that the belt does not sag, and temporarily tighten the center bolt.
"K" TIMING BELT TENSION ADJUSTMENT
1. Turn the crankshaft 1/4 turn counterclockwise, and then turn it clockwise to move the No.1 cylinder to top dead center.
2. Loosen the center bolt, and then, as shown in the illustration, attach the special tool and a torque wrench and apply a torque of 3.6 Nm (2.6 ft.lbs.). If the body interferes with the special tool and the torque wrench, use a jack to slightly raise the engine assembly.
NOTE: Use a torque wrench that is capable of measurement within a range of 0 - 5 Nm (0 - 3.7 ft.lbs.).
3. Holding the tensioner pulley with the special tool and torque wrench, tighten the center bolt to the specified torque.
4. Screw the tool into the engine left support bracket until its end touch the tensioner arm. At that point, screw the tool in some more and then remove the set wire attached to the auto tensioner.
5. Remove the tool.
6. Rotate the crankshaft two complete turns clockwise and leave it as is for about 15 minutes. Then, measure the auto tensioner protrusion "A" (distance between the tensioner arm and auto tensioner body).
Standard value: 3.8 - 4.5 mm (0.15 - 0.18 in.)
NOTE: If it is not within the standard value, repeat steps "1" through "6" until the specified value is obtained.
7. If the clearance between the tensioner arm and the auto tensioner body cannot be measured (when the engine is being mounted, etc.), the following procedures can be used to substitute for the ordinary method of measurement.
(1) Screw in the tool until it contacts the tensioner arm.
(2) From that point of contact, further screw in the tool, screwing it in until the push rod of the auto tensioner body moves backward and the tensioner arm contacts the auto tensioner body.
NOTE: Check that the amount that the tool has been screwed in (when the push rod moves backward) is within the standard value.
Standard value: 2.5 - 3 turns
8. Install the rubber plug to the timing belt rear cover.
"L" TIMING BELT LOWER / UPPER COVER INSTALLATION
NOTE: The dimensions of the installation bolts for the timing belt covers depend on installation location. Do not confuse them.
NOTE: As the bolts are integrated in the middle of 1993 model, two types of bolts are being established.