Assembling the flywheels. The importance of using an arbour press to
assemble the flywheels cannot be too highly stressed. To rely on tighten-
ing the crank pin nuts will result in a broken crank pin, due to the fly-
wheels flexing when the engine is under load. It is for this reason that
after fitting the crank pin, both flywheels must be forced together under
a press, so that the shoulder of the crank pin is hard against the flywheel.
It is after this operation that the nuts are tightened. The torque spanner
setting when cast iron flywheels are used is 140 ft. lbs. With engines that
have steel flywheels the torque setting is 190 ft. lbs.
If, after assembling the flywheels, the connecting rod is not free to
rotate, this could be due to one or both drive shafts moving inwards and
rubbing against the connecting rod. Drive home the shaft that is affected,
The flywheels should run true, in centres, to a limit of .001" to .002" and
no more,
Refitting the timing side bush. Locate and press in the bush, then fit the
locating pin, designed to prevent the bush moving. Replacement bushes
are sized to allow for contraction when in the crankcase. If the shaft will
not enter, or is a tight fit, ream the bush to .8755" to .8750". The bush
should be flush with the inside of the crankcase.
Refitting the drive side bearings. The crankcase should be gently heated
to fit the bearings, assemble in the following order:
Fit the bearing 012542—nearest to the engine sprocket.
Fit the stator 043036—locate with the tube, or bolt whichever is fitted.
Fit the bearing ring in the crankcase—“peen” the ring in three places.
Fit the centre member for the bearing on the drive shaft, fit the key
for the rotor 041021—then fit the rotor to engage with the key, apply oil
to it.
Insert flywheels into the drive side crankcase.
Apply jointing compound—“Wellseal”—to crankcase joint, verify all
oilways in the timing side crankcase are clear, then fit the case to the
drive side half.
Pass the seven bolts through the crankcase and tighten,
Check the small bolt for the oil pump plunger 042046—the tip may
have broken away. When renewing the “O” ring—fit this to the widest
of the two rings. Insert the plug 042044 chamfered end first and locate it
with the pin 042046 mentioned above.
Fitting the oil pump plunger. Apply some clean oil, insert the plunger
into the crankcase to a. depth of l
n" from the screwed plug face. Check
the end of the guide pin (which engages with the annular slot in the
plunger) for wear at the top end. A small flat worn at this end will curtail,
or cut off the oil supply to the rocker gear and a new pin must be fitted.
Using extreme care, screw in the sleeve with the guide pin 010079—the
reduced end goes inside the sleeve—and make sure that the guide pin
engages with the annular groove in the plunger. Do not use force, move
the plunger to engage the pin if necessary, use a spanner only when the
sleeve is fully home. Failure to observe these precautions can ruin the
plunger beyond further use.
Fit the housing plug 042045 with its washer. Firmly tighten as an air
leak at this point will affect the oiling system.
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