Generac Power Systems 53187 - Manual (Page 78)

PART 2
ENGINE MECHANICAL
Crankshaft (Continued)
3. W hen grinding the crankshaft, the foiiow ing specifi­
cations appiy (Figure 27);
A
Radius at PInAJoumal ■ 0.11B * 0.004 In. (3tnm-M).1mm)
В
Finish precision 1.62 (VW )
C
Radius around oil hole & 0.079 In. (2mm) шах., 0.020 In.
(0.5mm) mln.
NO TE: Use No. 400 sandpaper for final polishing.
Camshaft Assembly
Inspect the journals and cam s for w ear and dam ­
age. If allow able lim its are exceeded, replace the cam ­
shaft.
See Figure 28. Cam height tolerances are as fol­
low s;
A INTAKE/EXHAUST VALVE CAM HEIGHT;
Standard Value: 1.0413-1.0433 inch (26.45-
26.50m m )
Allow able Lim it: 1.0275 inch (26.1m m )
B
INJECTION PUM P CAM HEIGHT;
Standard Value: 0.9425-0.9472 Inch (23.94-
24.06m m )
Allow able Lim it: 0.9370 inch (23.8m m )
C
FUEL FEED PUM P CAM HEIGHT;
Standard Value: 1.0590-1.0630 inch (26.9-27.0m m )
Allow able Lim it: 1.0236 Inch (26.0m m )
Timing Gear
Inspect tim ing gears for w ear or dam age at their engag­
ing areas. Replace if dam aged or w orn excessively.
Use a thickness gauge or a dial indicator to m easure
gear backlash. If allow able lim its are exceeded, replace
the tim ing gears as a set.
1
SECTION 2.4
DISASSEMBLY AND INSPECTION
Figure 28. Cam shaft Assem bly
BACKLASH OF TIMING GEARS:
Standard Backlash: 0.003 inch (0.08m m )
Allow able Lim it: 0.010 Inch (0.25m m )
Oil Pump
REMOVAL AND DISASSEMBLY;
1. See Figure 30. Rem ove the SNAP RING.
2. Rem ove COLLAR, SPRING and SHIM .
3. Rem ove IDLE GEAR, VANE and OIL PUM P COVER
as a unit.
4. Rerm ove ROTOR and THRUST W ASHER.
5. Rem ove OIL PUMP COVER from the IDLE GEAR.
6. Rem ove SPRING from the IDLE GEAR. Rem ove the
KNOCK PIN.
7. Rem ove the VANE from the IDLE GEAR.
Thrust w asher
Spring
Rotor r
Shim ' ’ vine Idle gear
Collar • Oil pum p cover
-Spring
Knock
■ I pin
Snap ring
Figure 30. Oil Pump Assembly
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