Section 11: Crankshaft And Camshaft - Generac Power Systems GTV-990 Manual

SECTION CONTENTS
CHECK CRANKSHAFT .................................................. 11-1
CHECK CAMSHAFT .................................................... 11-1
CHECK CRANKSHAFT:
Inspect crankshaft threads, keyways and timing gear for
damage or wear. If threads, keyways or timing gear are dam-
aged or worn, replace crankshaft. Check journals for scoring.
If journals are scored, replace crankshaft. Check journals for
wear. See crankshaft reject sizes.
Crankshaft Reject Sizes
Model PTO
Series Journal
ALL 41.85 mm
(1.648")
MAG
JOURNAL
FLYWHEEL
KEY
OIL
GALLERY
Figure 11-1. Check Crankshaft
PAGE
Mag. Crankpin
Journal Journal
37.85 mm 38.96 mm
(1.490") (1.534")
OIL
GALLERIES
PTO
JOURNAL
TIMING
CRANKPIN
GEAR
SECTION 11: CRANKSHAFT & CAMSHAFT
CHECK CAMSHAFT:
Inspect gear teeth, lobes and journals for wear and nicks,
Figure 11-2. Camshaft journal and lobe reject sizes are shown
below. Replace cam gear if not to specification.
Camshaft Reject Size
PTO Mag
Journal Journal
17.93 mm 19.93 mm
.784")
(0.705") (0
INTAKE
LOBES
MAG
JOURNAL
Figure 11-2. Check Camshaft
11-1
Intake Exhaust
Lobes
31.02 mm 31.02 mm
1.221") 1.221")
( (
EXHAUST
PTO
LOBES
JOURNAL
lobes