Crankcase Cover - Generac Power Systems OHVI GSH 220 Service Manual

SeCTIoN 9: lubrICATIoN SYSTeM
CrANkSHAFT oIl SeAlS
DESCRIPTION:
An oil seal is provided in the crankcase cover and in the
crankcase to prevent oil leakage past the crankshaft journals
(Figure 9-8).
OIL SEAL
Figure 9-8. Crankshaft Oil Seals
SEAL REPLACEMENT:
A leaking or otherwise defective oil seal can be replaced as
follows:
. If the crankshaft has been removed, old seals can be
removed by tapping out with a screwdriver or by tapping
them out from the inside.
2. If the crankshaft is installed, use a commercially available
oil seal puller to remove the seals.
. Always use a seal protector when installing the crankshaft
into its bearing bore and when installing the crankcase
cover over the crankshaft.
breATHer ASSeMblY
DESCRIPTION:
A crankcase breather is located in the rocker arm cover of
horizontal crankshaft engines (Figure 9-9). The breather serves
to maintain a reduced pressure in the engine crankcase, to
prevent oil from being forced past the oil seals, gaskets or
piston rings.
The CHECK VALVE allows excess pressure to be vented out
of the crankcase and to the air inlet side of the carburetor
through the BREATHER TUBE. Two small DRAIN HOLES allow
condensed oil vapors to return to the crankcase.
NOTE: The crankcase breather on vertical shaft GN/GSH/
GSV series engines is mounted on the crankcase assem-
bly and is configured differently. See "SERVICE MANUAL.
COMPUTER CONTROLLED VARIABLE SPEED RV GENERA-
TORS," Manual Part No. 094468-A.
ROCKER
ARM
COVER
OIL SEAL
INSPECTION:
. Remove the breather tube. Check tube for cracks, harden-
ing or other damage. Replace if necessary.
2. Clean the rocker arm cover with a commercial solvent.
. Make sure the two small drain holes are open. If necessary,
use a length of wire to open the holes.
. Check the rivets that retain the check valve, make sure
they are tight.
5. The breather plate is retained in the rocker arm cover
with a continuous bead of Type 0 black RTV sealant.
This sealant must not leak. Test the sealant for leakage as
follows:
a. Seal all holes on the breather plate.
b. Apply air pressure of 5 psi (0.52 kg/cm ) through the
breather hose hole. No leakage must be observed.
c. If necessary, reseal the plate with Type 0 black RTV
sealant.
DESCRIPTION:
The die-cast aluminum crankcase cover is retained to the
crankcase with flanged head bolts.
Install a new gasket between the cover and crankcase each
time the cover is removed. Machined bores are provided in
the cover for (a) oil pump rotors and camshaft, (b) crankshaft,
(c) balancer (Large Frame engines only), (d) governor gear
assembly and (e) the oil pickup assembly. Cored oil passages
are provided from the pickup bore to the pump and from the
pump to the crankshaft bore.
9-
CHECK
DRAIN
VALVE
HOLE
Figure 9-9. Crankcase Breather

CrANkCASe Cover

BREATHER
TUBE