Engine Inspection and Repair
CLEANING FRONT, INTERMEDIATE & REAR HOUSINGS1. Remove all carbon on the housings with an extra-fine emery paper. If using a carbon scraper, be careful not to damage the finished surfaces of the housings.
2. Remove the sealing agent from housings by using a cloth or a brush soaked in a solution of ketone or thinner.
CLEANING ROTOR HOUSING
Before cleaning, check for traces of gas or water leakage along the inner margin of each side face of the rotor housing.
1. Remove all carbon from the inner surface of the rotor housing by wiping with cloth. Soak the cloth in a solution of ketone or thinner if it is difficult to remove the carbon.
2. Remove all deposits and rust from the cooling water passages on the housing.
3. Remove the sealing agent by wiping with a cloth or brush soaked in a solution of ketone or thinner.
CLEANING ROTOR
Remove the carbon from rotor by using a carbon remover or emery paper. Carbon in the seal grooves of the rotor should be removed with a carbon remover being careful not to damage the grooves. Wash the rotor in cleaning solution and dry by blowing with compressed air.
CLEANING APEX SEAL, SIDE PIECE & SPRING
Remove all carbon from the apex seal, side piece and spring, being careful not to damage the apex seal and side piece.
Never use emery paper as it will damage the apex seal and side piece. Wash them with cleaning solution.
CLEANING SIDE SEAL & SPRING
Remove all carbon from the side seal and spring with a carbon remover.
CLEANING CORNER SEAL & SPRING
Remove the carbon from the corner seal and spring.
Fig. 8 Checking housing for distortion:
INSPECTING FRONT, INTERMEDIATE & REAR HOUSINGS
1. Check for housing distortion by placing a straightedge on the housing surface. Measure the clearance between the straight edge and the housing surface with a feeler gauge, as shown in Fig. 8. If the distortion exceeds 0.0016 in. (0.04 mm), reface or replace the housing.
Fig. 9 Checking housing side seal wear:
2. Check contact surface for wear with dial indicator mounted on tool 490727570 or equivalent, Fig. 9.
a. Side seal wear must not exceed 0.0039 inch (0.1 mm).
Fig. 10 Checking housing side seal wear:
b. Side seal wear, overlapping oil seal wear (2), Fig. 10, must not exceed 0.0004 inch (0.01 mm).
c. Side seal wear, outside oil seal wear (3), Fig. 10, must not exceed 0.0039 inch (0.1 mm).
Fig. 11 Checking housing oil seal wear:
d. Oil seal wear (4), Fig. 11, must not exceed 0.0008 inch (0.02 mm).
3. Replace housing as necessary.
INSPECTING STATIONARY GEAR & MAIN BEARING
1. Check the stationary gear for cracked, scored, worn or chipped teeth.
2. Check the main bearing for wear, scratching, flaking or any damage.
3. Check the main bearing clearance by measuring the inner diameter of the main bearing and outer diameter of the eccentric shaft main journal. Standard clearance is 0.0016-0.0031 inch (0.04-0.08 mm). If bearing clearance exceeds 0.0039 inch (0.10 mm), replace the main bearing.
Fig. 12 Removing front stationary gear:
REPLACING FRONT MAIN BEARING
1. Remove the stationary gear and main bearing assembly from the front housing, using the puller and installer (49 0813 235), as shown in Fig. 12.
2. Using the main bearing replacer without adapter ring, press the main bearing out of the stationary gear.
Fig. 13 Removing and installing main bearing:
3. Using the main bearing replacer with adapter ring, and aligning the tang of the bearing and the slot of the stationary gear, press fit the main bearing into the stationary gear until the adapter touches the stationary gear flange, Fig. 13.
Fig. 14 Installing front stationary gear:
4. Press in the stationary gear to the front housing with the main bearing replacer, aligning the slot of the stationary gear flange and the dowel pin on the housing, as shown in Fig. 14.
Fig. 15 Removing rear stationary gear:
REPLACING REAR MAIN BEARING
1. Remove the bolts attaching the stationary gear to the rear housing.
2. Using the puller & installer (49 0813 235), remove the stationary gear from the rear housing, Fig. 15.
3. Check the O-ring on the stationary gear for damage. Replace the O-ring if necessary.
4. Using the main bearing replacer without adapter ring, press the main bearing out of the stationary gear.
5. Use the main bearing replacer with adapter ring, and aligning the tang of the bearing and the slot of the stationary gear, press fit the main bearing into the stationary gear until the adapter touches the stationary gear flange.
6. Apply a thin coat of petroleum jelly on the O-ring and place it in the groove of the stationary gear.
7. Apply sealing agent onto the stationary gear flange.
Fig. 16 Installing rear stationary gear:
8. Install the stationary gear to the rear housing, being careful not to damage the O-ring and aligning the slot of the stationary gear with the dowel pin on the rear housing, Fig. 16.
9. Tighten the bolts attaching the stationary gear.
INSPECTING ROTOR HOUSING
1. Check the chromium plated surface on the rotor housing for scoring, flaking or any damage. If any of these conditions exists excessively, replace the rotor housing.
Fig. 17 Checking rotor housing width points:
2. Check the rotor housing width at points close to the trochoid surface by using a micrometer. The measurements should be taken at four points, as shown in Fig. 17. If the difference between the value of point A and the minimum value among the points B, C and D exceeds 0.0024 in. (0.06 mm), the rotor housing should be replaced with a new one.
INSPECTING ROTOR
1. Carefully inspect the rotor and replace if it is severely worn or damaged.
2. Check the internal gear for cracked, scored, worn or chipped teeth.
Fig. 18 Checking rotor width:
3. Check the clearance between the side housing and the rotor by measuring the rotor housing width and rotor width. The rotor width should be measured at three points, as shown in Fig. 18.
Fig. 17 Checking rotor housing width points:
4. The difference between maximum width of rotor and width of point A of rotor housing, Fig. 17. Clearance should be 0.0047-0.0074 inch (0.12-0.19 mm) on 1984-85 models less fuel injected engine or 0.0047-0.0083 inch (0.12-0.21 mm) on 1984-88 models with fuel injected engine.
5. If the clearance is more than the specification, replace the rotor assembly. If the clearance is less than the specification, it indicates that the internal gear has come out, so strike the internal gear lightly with plastic hammer, being careful not to damage, then recheck the clearance between the side housing and the rotor.
Fig. 19 Checking corner seal bore:
6. Check the corner seal bores for wear with the gauge (49 0839 165), Fig. 19, noting the following:
a. If neither end of the gauge goes into the bore, use the original corner seal.
b. If the not-go-end of the gauge does not go into the bore while the go-end does, replace with a new corner seal.
c. If both ends of the gauge go into the bore, replace the rotor.
INSPECTING ROTOR BEARING
1. Check the rotor bearing for wear, flaking, scoring or any damage. If any of these conditions are found, replace the bearing.
Fig. 20 Checking rotor bearing clearance:
2. Check the rotor bearing clearance by measuring the inner diameter of the rotor bearing and outer diameter of the eccentric shaft rotor journal, as shown in Fig. 20. The standard clearance is 0.0016-0.0031 in. (0.04-0.08 mm). Replace the bearing if it is more than 0.0039 in. (0.10 mm).
REPLACING ROTOR BEARING
1. Place the rotor on the support so that the internal gear is facing downward. Using the puller and installer (49 0813 240) without adapter ring, press the bearing out of the rotor, being careful not to damage the internal gear.
2. Place the rotor on the support with internal gear faced upward, and place the new rotor bearing on the rotor so that the bearing lug is in line with the slot of the rotor bore.
3. Remove the screws attaching the adapter ring to the replacer. Using the replacer and adapter, press fit the new bearing until the bearing is flush with the rotor boss.
INSPECTING ROTOR OIL SEAL & SPRING
1. Check the oil seal for wear or any damage. If the lip width of the oil seal is more than 0.02 in. (0.5 mm), replace the oil seal.
2. Check the free movement of the oil seal in the rotor groove by pressing with finger.
Fig. 21 Checking oil seal protrusion:
3. Check the oil seal protrusion as shown in Fig. 21 and replace the oil seal spring if the protrusion is less than 0.02 in. (0.5 mm).
INSPECTING APEX SEAL, SIDE PIECE & SPRING
1. Check the apex seal and side piece for wear, crack or any damage. If any of these conditions is found, replace the seal. Check the spring for wear.
Fig. 22 Apex seal height:
2. Measure the height of the apex seal with a micrometer at two positions shown in Fig. 22. Replace if the height is less than 0.276 in. (7.0 mm) for 1984-85 models or 0.256 in. (6.5 mm) for 1986-88 models. On 1986-88 models, replace short apex seal spring, if apex seal height is below 0.295 in. (7.5 mm).
3. Place two apex seals together, top-to-top, and measure warpage using a feeler gauge. Repeat with all three seals. If clearance exceeds 0.0024 in. (0.06 mm), replace all three rotor apex seals.
4. Check the clearance between the apex seal and the groove. To check the clearance, place the apex seal in its respective groove on the rotor and measure the clearance between the apex seal and the groove with a feeler gauge. The feeler gauge should be inserted until the tip of the gauge reaches the bottom of the groove. The standard clearance is 0.0020-0.0035 in. (0.05-0.090 mm) for 1984-85 models, 0.0024-0.0040 in. (0.062-0.102 mm) for 1986-87 and 1988 non-Turbo models, or 0.002-0.004 inch (0.054-0.101 mm) on 1988 Turbo models. If the clearance is more than 0.15 mm (0.0006 in.), replace the apex seal.
Fig. 23 Checking apex seal spring:
5. Check the free height of apex seal spring, Fig. 23. Free height should measure 0.2165 inch (5.5 mm) on 1984 models with 12A engine, 0.1496 inch (3.8 mm) on 1984-85 models with 13A engine, 0.181 inch (4.6 mm) for long spring on 1986-88 models or 0.118 inch (3 mm) for short spring on 1986-88 models.
INSPECTING SIDE SEAL & SPRING
1. Check the free movement of the side seal in the rotor groove by pressing with finger.
2. Check the side seal protrusion from the rotor surface and replace the side seal spring if the protrusion is less than 0.02 in. (0.5 mm).
Fig. 24 Checking side seal clearance:
3. Check clearance between side seal and the groove with a feeler gauge, Fig. 24. Standard clearance is 0.0011-0.0031 inch (0.03-0.08 mm). If clearance exceeds 0.0039 inch (0.10 mm), replace side seal.
Fig. 25 Checking side seal to corner seal clearance:
4. Using a feeler gauge, check the clearance between the side seal and the corner seal with these seals installed on the rotor, Fig. 25. If the clearance exceeds 0.016 in. (0.4 mm), replace the side seal. When the side seal is replaced, adjust the clearance between the side seal and the corner seal by grinding the one end of the side seal along the round shape of the corner seal with a fine file so that the clearance will be 0.002-0.006 in. (0.05-0.15 mm).
INSPECTING CORNER SEAL & SPRING
1. Check the corner seal for wear, crack or any damage. If any of these conditions is found, replace the seal. Check the spring for wear.
2. Check the free movement of the corner seal in the rotor groove by pressing with finger.
Fig. 26 Checking corner seal protrusion:
3. Check the corner seal protrusion, Fig. 26, from the rotor surface and replace the corner seal spring if the protrusion is less than 0.02 in. (0.5 mm).
INSPECTING ECCENTRIC SHAFT
1. Check the shaft for cracks, scratches, wear or any damage. Be sure that the oil passages are open.
2. Check the shaft for run out. To check, mount the shaft on V-blocks and install a dial indicator. Slowly rotate the shaft and note the reading on the indicator. If the run out is more than 0.0024 in. (0.06 mm) for 1984-85 models or 0.0047 in. (0.12 mm) for 1986-88 models, replace the shaft with a new one.
Fig. 27 Eccentric shaft and related components:
3. Check the blind plug in the shaft end for oil leakage or looseness. If any oil leakage is found, remove the blind plug with a hexagonal Allen key and replace the O-ring, Fig. 27.
4. The oil jets are installed in the eccentric shaft. The oil jets open when engine speed increases and oil pressure rises. Check for spring weakness, sticking or damage of the steel ball.
INSPECTING NEEDLE BEARING
Check needle bearing for wear or damage. Inspect bearing housing and thrust plate for wear or any damage.
INSPECTING ECCENTRIC SHAFT FRONT & REAR OIL SEALS
Check the front oil seal fitted into the front cover and the rear oil seal fitted into the rear stationary gear. If it is worn or damaged, replace the oil seal as follows:
1. Remove the oil seal by using a suitable tool.
2. Clean the oil seal mounting bore.
3. Position a new oil seal on its mounting bore and place a block of wood on the oil seal. Install the oil seal while tapping the wooden block with a hammer until it is firmly seated. Do not coat the outer surface of the oil seal with any lubricant or sealing agent. Do not tap the oil seal directly with a hammer.
CHECKING OIL PUMP DRIVE CHAIN SPROCKETS
Check the oil pump drive chain for broken links. Check the eccentric shaft sprocket and oil pump sprocket for cracks and worn or damaged teeth. If any defects are found, replace with new parts.