Basic Engine
With the rotor assembly installed in the housing, place a
OD of the shaft and the ID of the housing bearing. Inspect the
straight edge over the rotor assembly and the housing.
relief valve spring for a collapsed or worn condition Check the
Measure the clearance (rotor end play) between the straight
relief valve spring tension. If the spring tension is not within
specifications and/or the spring is worn or damaged replace
edge and the rotor and outer race (Figure 22). The outer
the spring. Check the relief valve piston for scores and free
race, shaft and rotor are replaceable only as an assembly.
operation in the bore
Check the drive shaft to housing bearing clearance by
measuring the
POSITIVE CLOSED-TYPE CRANKCASE
VENTILATION SYSTEM
Cleaning
Do not attempt to clean the crankcase ventilation
regulator valve; it should be replaced at the specified
maintenance interval. The oil filler cap and oil separator
should be cleaned at the proper maintenance interval.
Remove the cap and the oil separator and wash them in a low-
volatility. petroleum-base solvent. Shake the cap dry and
install them.
Clean the crankcase ventilation system
connection(s) on the intake manifold by probing with a flexible
wire or bottle brush. Clean the hoses, fittings. tubes and
associated hardware with a low-volatility, petroleum-base
solvent and dry with compressed air.
FIG. 22. Checking Rotor End Play
OVERHAUL
CYLINDER HEAD
Replace the head if it is cracked. Do not plane or grind
more than 0.010 inch from the cylinder head gasket
surface. Remove all burrs or scratches with an oil stone.
REAMING VALVE GUIDES
If it becomes necessary to ream a valve guide (Figure 23)
to install a valve with an oversize stem, a reaming kit is
available which contains the following reamer and pilot
combinations: a 0.003-inch OS reamer with a standard
diameter pilot, a 0.015-inch OS reamer with a 0.003-inch OS
pilot, and a 0.030-inch reamer with a 0.015-inch OS pilot.
When going from a standard size valve to an oversize
valve always use the reamer in sequence. Always reface the
valve seat after the valve guide has been reamed, and use
a suitable scraper to break the sharp corner (ID) at the top
of the valve guide.
REFACING VALVE SEATS
Refacing the valve seat should be closely coordinated
with the refacing of the valve face so that the finished seat and
valve face will be concentric and the specified interference fit
will be maintained. This is important so that the valve and seat
will have a compression-tight fit. Be sure that the refacer
FIG 23. Reaming Valve Guides
grinding wheels are properly dressed.
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