Crankcase, Crankshaft, Main Bearings & Flywheel

1.PREPARATION :

Check and fill the cooling system. Check the level of oil in the crankcase. Bleed the fuel system using the hand primer pump located on fuel filter. Start the engine and run with the throttle at 1/4 position until the engine attains the operating temperature.

2.DISMANTLING

a)Remove the crankshaft spin-on and clutch shaft pilot bearing if inspection proves this necessary.

b)Remove the oil seal from the rear oil seal retainer.

3.INSPECTION AND REPAIR

a)Check the main journals and crankpins for wear and taper. Grind if necessary to the dimensions shown in Fig. 7.

b)Check the dowels for wear or damage, replace if necessary pressing into the dimension shown in Fig. 5.

c)Check the clutch shaft pilot bearing for wear or damage, replace if necessary pressing into the dimension shown in Fig. 5.

d)Check that the oil ways are clear.

4.ASSEMBLY

a)Install the clutch shaft pilot bearing if it was removed.

b)Install the dowels if they were removed.

c)Install a new key and the crankshaft spin-on if they were removed.

d)Press a new oil seal into the rear oil seal retainer with the lip toward the front of the crankcase. The seal must be pressed hard against the shoulders of the retainer.

5.INSTALLATION

a)Install the upper half bearing inserts and lubricate them.

b)Carefully install the crankshaft and spin it by hand.

c)Install the main bearing caps.

d)Install the connecting rods, connecting rod bearings and bearing caps to the crankshaft with the identification numbers to the fuel injection pump side then tighten the bolts to the specified torque.

e)Check the connecting rod side clearance to specifications.

f)Use jointing compound and fit a new horseshoe gasket to the rear face of the crankcase lining up the holes in the gasket with the bolt holes.

g)Apply a light coating of grease to the oil seal and fit the oil seal retainer over the end of the crankshaft taking care not to damage the lip of the seal. If possible use a sleeve for this operation. Ensure that the seal garter spring is in position.

h)Locate the retainer on the dowels, install the bolts and to ensure even seating of the gasket, tighten the bolts by stages to the specified torque.

NOTE: The bottom face of the retainer, after installation, must be in line with the bottom face of the crankcase within 0.020”.

(i)Trim the horseshoe gasket flush with the bottom of the crankcase.

(j)Install adapter plate and oil pan, use liquid gasket (loctite 584) for these joints.

(k)Install the flywheel.

(l)Install the oil pump.

(m)Invert the engine.

(n)Install the crankcase front cover.

E.HELI-COIL THREAD INSERTS

1.REMOVAL a)Place the extractor into the insert and turn in an anti-clockwise direction.

2.INSTALLATION a)Place a new insert in the driver with the driving lug to the bottom. b)Screw the insert into the tool guide until it is flush with the end of the tool. c)Place the driver over the tapped hole and turn the handle clockwise until the insert leaves the tools, then break off the driving lug. Ensure that inserts are driven into the specified depth.

NOTE: Never use an insert that has been removed.