Generac Power Systems OHVI GSH 220 Service Manual page 14

SeCTIoN 3: AIr INTAke SYSTeM ANd CArbureTIoN
AIR CLEANER BOX REMOVAL (SMALL FRAME):
If the air cleaner box must be removed for further engine
disassembly, follow Steps - from Large Frame Air Cleaner
Box Removal. Then do the following:
. Remove the cap screw in the upper part of the air cleaner
box and the two phillips head screws in the lower part of
the air cleaner box (see Figure -).
*
CAuTIoN! removal of the two phillips head screws
on a choke style carburetor/air cleaner box combina-
tion also will loosen the carburetor from its mount.
be careful not to let the carburetor drop, as damage
to the carburetor and/or governor rod and anti-lash
spring may result.
GASKET
AIR CLEANER BOX
Figure 3-3. Removal of Air Cleaner Box,
Primer Style Carburetor
AIR CLEANER BOX INSTALLATION:
Install the air cleaner box to the engine and carburetor as
follows:
. Using a new gasket, place the air cleaner box on the
carburetor, line up the holes and install the two nuts and
corresponding washers to the carburetor mounting bolts
(see Figure -2). Refer to "TORQUE SPECIFICATIONS" in
the back of this manual for proper torque.
Note: On large frame engines the nut on the right side
(toward the rear of the engine) uses only a flat washer.
The nut on the left side (toward the front of the engine)
uses a lock washer and a flat washer (see Figure 3-2).
2. Install the capscrews in the air cleaner box (see Figure -2).
Refer to "TORQUE SPECIFICATIONS" in the back of this
manual for proper torque.
. Reinstall the breather hose.
. Reinstall the choke knob.
5. Install the filters and cover as stated in the preceding sections
on filter maintenance.
BREATHER HOSE
CAP SCREW
PAPER FILTER
FOAM
PRE-CLEANER
PHILLIPS HEAD SCREWS
CArbureTIoN
GENERAL:
Proper engine performance depends on the carburetion
system. The use of clean, fresh fuel and a well maintained air
cleaner is extremely important to engine operation, as well as
engine reliability and power.
COMMON CARBURETOR PROBLEMS:
Most causes of carburetor problems are related to the use
of stale, gummy fuel and the ingestion of dirt. Prior to servic-
ing any carburetor, be sure to check for evidence of these
conditions.
Gasoline that is left in the system for long periods can form
gum or varnish deposits that will adversely affect carburetor
operation.
NOTE: Use of a good fuel stabilizer will minimize the
formation of gum deposits during storage. Add the
stabilizer to the gasoline in the fuel tank or in the stor-
age container. Follow the mix ratio recommended on
the stabilizer container. After adding the stabilizer to
the engine fuel tank, run the engine for about ten (10)
minutes so it will enter the carburetor. A brand name
stabilizer can be purchased at a Generac Air-Cooled
Industrial Engine Dealer.
SERVICE TIP:
Carefully inspect the carburetor choke and throttle shafts for
wear. Grasp each shaft and attempt to move it horizontally
and vertically. Maximum allowable end play for choke and
throttle shafts is 0.00 inch (0.mm). Replace if excessive play
is evident.
CARBURETOR REMOVAL:
. Remove the air cleaner box as outlined in "AIR CLEAN-
ER BOX REMOVAL."
2. Disconnect the governor rod and anti-lash spring from the
throttle arm of the carburetor.
. Slide the carburetor off of its mounting bolts.
CARBURETOR DISASSEMBLY:
To disassemble the carburetor, proceed as follows (See Figure
-5 or -6):
. Remove the FLOAT BOWL NUT and the FIBER WASHER.
Then remove the FLOAT BOWL.
2. Remove the FLOAT PIN. Then remove the FLOAT, and FUEL
INLET VALVE.
. Remove the IDLE SPEED STOP SCREW along with its
SPRING.
-2