Section 11: Crankshaft, Camshaft And Balancer 1 - Generac Power Systems OHVI GSH 220 Service Manual

CrANkCASe Cover reMovAl
Before attempting to remove the crankcase cover, remove
all rust, burrs and paint from the power take-off (PTO) end of
the crankshaft. This will reduce the possibility of damaging the
oil seal in the crankcase cover during cover removal. Remove
the crankcase cover as follows:
. Drain oil from the crankcase.
2. Remove the engine cylinder head, push rods and push rod
guide plate (see Section 6).
. Remove all flange head bolts that retain the crankcase
cover.
. Remove the crankcase cover (Figure -). If necessary,
tap lightly with a soft hammer on alternate sides of cover.
Be aware that the oil pump rotors may drop out as the
crankcase cover is removed.
CRANKCASE
COVER BOLT
CRANKCASE
COVER
CRANKCASE
Figure 11-1. Crankcase Cover Removal
CrANkSHAFT CAMSHAFT ANd bAlANCer reMovAl
With the crankcase cover removed, the crankshaft and cam-
shaft (and balancer on large frame engines) can be removed
from their crankcase bores. Remove these components as
follows (see Figure -2):
. Tip the engine over onto the flywheel end of the
crankshaft.
2. Reach in with two fingers and hold the tappets up and
clear of the camshaft lobes. Then, remove the camshaft,
both tappets, and the inner and outer oil pump rotors.
Note: Some models may be equipped with a camshaft
spring washer.
. Remove the balancer (large frame engine only).
. Before removing the crankshaft, remove the engine fly-
5. Turn the crankshaft to access the two (2) connecting rod
6. Remove the connecting rod bolts and connecting rod
7. Push connecting rod and piston up and out of cylinder.
follows:
. Check for physical damage. Replace the balancer if
2. Measure the outside diameter (O.D.) of the balance shaft
CRANKCASE
NOTE: Refer to "ENGINE SPECIFICATIONS", Section 15, in
COVER GASKET
this manual for design sizes and wear limits.
. Measure the inside diameter (I.D.) of the balancer shaft
-
SeCTIoN 11: CrANkSHAFT & CAMSHAFT
wheel (see Section 2).
bolts.
cap.
bAlANCer INSPeCTIoN
(lArGe FrAMe eNGINeS, FIGure 11-3)
Clean the balancer in solvent. Then inspect the balancer as
damaged.
ends. Replace balancer if wear limits are exceeded.
bearing bore in the crankcase cover and in the crankcase.
a. If balancer bearing bore in crankcase cover exceeds wear
limits, replace the crankcase cover (see Section 5).
b. If balancer bearing bore in crankcase exceeds wear limits,
replace the crankcase assembly (see Section 5).
OIL PUMP
CAMSHAFT
Figure 11-2. Crankshaft, Camshaft and Balancer Removal
1 1
BALANCER
CRANKSHAFT