Inspection; Crankshaft Oil Seals - Generac Power Systems GN190H Service And Repair Manual

OIL PUMP (CONTINUED)

INSPECTION:

1. Inspect the inner and outer rotors for damage and wear
(Figure 12.4).
2. Use a feeler gauge to check tip clearance of inner rotor,
with rotor installed on shaft in crankcase cover.
3. Measure the bore inner diameter of the inner rotor.
4. Measure the inner rotor thickness.
5. Check the outer rotor outside diameter.
6. Inspect the outer rotor drive pins on the camshaft. Check
for breaking, bending or other damage. The two roll pins
can be removed and replaced with relative ease.
Replace any oil pump component that is damaged or worn
excessively.
NOTE: The shaft on which the inner oil pump rotor
rotates is NOT replaceable. If the shaft is damaged or
worn, the crankcase cover must be replaced.
Tip Clearance of Rotor
Rotor Thickness
Figure 12.4 — Inner and Outer Rotor Check Points
OIL PUMP INNER
ROTOR SHAFT O.D.
DESIGN DIAMETER = 0.353-0.354 inch
Inner Rotor I.D.
Outer Rotor O.D.
(8.969-8.987mm)
OIL PUMP ROTOR TIP CLEARANCE
DESIGN CLEARANCE = 0.0000-0.0010 inch
INNER ROTOR I.D.
DESIGN DIAMETER = 0.354-0.355 inch
INNER ROTOR THICKNESS.
DESIGN THICKNESS = 0.312-0.315 inch
OUTER
ROTOR THICKNESS.
DESIGN THICKNESS = 0.314-0.316 inch
OUTER
ROTOR O.D.
DESIGN THICKNESS = 1.296-1.297 inch

CRANKSHAFT OIL SEALS

An oil seal is provided in the crankcase cover and in the
crankcase to prevent oil leakage past the crankshaft jour-
nals (Figure 12.5).
A leaking or defective oil seal can be removed and replaced
as follows:
1. If the crankshaft has been removed, old seals can be
removed by tapping out with a screwdriver or by punch-
ing them out from the inside.
2. If the crankshaft is installed, use a commercially available
oil seal puller to remove the seals.
3. Always use a seal protector when installing the crankshaft
into its bearing bore and when installing the crankcase cover
over the crankshaft.
OIL
SEAL
Figure 12.5 — Crankshaft Oil Seals
47
SECTION 12: LUBRICATION
(0.000-0.025mm)
(9.000-9.019mm)
(7.95-8.00mm)
(8.000-8.025mm)
(32.92-32.95mm)
OIL
SEAL