Timing Cover: Service and Repair
DISASSEMBLYFig. 27 Front Case, Oil Pump & Silent Shaft Assembly.:
Disassemble front case, oil pump and silent shaft in numbered sequence, noting the following:
1. Use oil pressure switch socket No. MD998054 or equivalent to remove oil pressure switch.
2. Remove oil pan, refer to OIL PAN.
Fig. 28 Removing Flange Bolt.:
3. When removing oil pump driven gear flange bolt, insert a Phillips screwdriver into plug hole on left side of cylinder block, to block the silent shaft.
Fig. 29 Removing Front Case.:
4. If front case will not come loose from block once all attaching bolts are removed, insert a flat screwdriver into slot as shown and pry case away from block. Do not pry in any other location on case.
Fig. 30 Removing Silent Shaft Front Bearings.:
5. Using silent shaft bearing puller MD998282 or equivalent, remove silent shaft front bearings as shown.
Fig. 31 Removing Silent Shaft Rear Bearing.:
6. Using silent shaft bearing puller MD998283 or equivalent, remove silent shaft rear bearings as shown.
INSPECTION
1. Inspect silent shaft for the following:
a. Clogged oil passages.
b. Seized or damaged journal.
c. Ensure oil clearance is within specifications. Clearance should be as follows: right front, 00012 - 0.0024 inch; right rear, 0.0020 - 0.0036 inch; left front, 0.0008 - 0.0021 inch; left rear, 0.0020 - 0.0036 inch.
2. Inspect front case for the following:
a. Clogged oil passages.
b. Damaged or seized left silent shaft front bearing section.
c. Cracks or other signs of damage on case.
3. Test oil switch as follows:
a. Connect an ohmmeter between switch terminal and switch body.
b. If ohmmeter reads no continuity, replace switch. If ohmmeter reads continuity, proceed to step c.
c. Insert a fine wedge into oil switch hole. Ohmmeter should read no continuity when wedge is slightly pressed into hole, If ohmmeter reads continuity, replace switch.
Fig. 32 Checking Oil Pump Tip Clearance.:
4. Inspect oil pump as follows:
a. Install oil pump gears in front case and check tip clearance in location shown.
b. Check side clearance of gears.
c. Check for for ridge wear on surface of oil pump cover.
5. Inspect oil relief plunger. Ensure plunger slides smoothly and spring is functional.
ASSEMBLY
Reverse removal procedure to install, noting the following:
1. When installing silent shaft rear bearing, apply clean engine oil to engine block bearing hole and to outer circumference of bearing. Using bearing installation tool No. MD998286 or equivalent and a hammer, drive bearing into cylinder block.
2. Install silent shaft front bearing as follows:
Fig. 33 Installing Silent Shaft Front Bearing.:
a. Using bearing installation tool set No. MD998280 or equivalent, install two guide pins (included in set) into threaded holes of cylinder block.
b. Place bearing onto bearing installer, locking ratchet ball of tool into hole in bearing.
c. Apply clean engine oil to engine block bearing hole and to outer circumference of bearing.
d. Place installation tool on guide pins, then using a hammer, drive bearing into cylinder block.
3. Install crankshaft oil seal using oil seal installation tool No. MD998304 or equivalent.
4. Install silent shaft oil seal by placing a socket over the top of the seal and pressing it into the case.
Fig. 34 Front Case Attaching Bolts.:
5. Install front case as follows:
a. Place crankshaft front oil seal guide NO. MD998285 or equivalent over front end of crankshaft, then apply engine oil to outer circumference of guide.
b. Install front case over top of guide, onto cylinder block.
c. Install case attaching bolts, referring to bolt length chart.
6. When installing oil pump gears, align mark on drive gear notch with mark on driven gear tooth.
7. When installing flange bolt (14), insert a Phillips screwdriver into plug hole on left side of cylinder block, to block the silent shaft. Tighten flange bolt and remove screwdriver.
8. When installing oil pump cover gasket, ensure round side of gasket faces oil pump cover.
9. Install oil pan, refer to OIL PAN.
10. When installing oil pressure switch, coat threads of switch with gasket adhesive. Do not allow hole in end of switch to be covered with adhesive. Install switch using oil pressure switch socket No. MD998054 or equivalent.