Onan CCK Service Manual

Assembly (Figure 20)
When replacing the cover on the thermostat and
heater assembly, be certain that the choke heater
lead wires have been correctly installed in the choke
housing. Improper replacement of the lead wires can
cause the choke assembly to malfunction.
The wires enter the choke assembly through a small
notch that is cut in the edge of the housing. A cover
holds the wires in place and prevents movement
when tightened. When properly installed, the lead
wires will hang freely under the bimetal coil when the
choke is in either the open or closed position. The
end of the heater wire sleeve should be located from
1/8 inch inside the choke housing to flush with the
inside wall.
When assembling the thermo-magnetic choke, the
bimetal and heater assembly is connected as follows:
1. Lead tagged G goes to ground terminal on coil
solenoid.
2. Lead tagged H goes to either H 1 terminal on
solenoid core.
FUEL PUMP
A diaphragm-type fuel pump is used. If fuel does not
reach the carburetor, check the fuel pump before
dismantling it.
The pump can be checked by disconnecting the fuel
line at the carburetor, cranking the engine slowly by
hand, and observing whether fuel comes from the line
at the carburetor. If there is enough fuel in the tank,
and the line between the tank and the pump is open
but the pump fails, repair or replace it. Failure of the
pump is usually due to a leaking diaphragm, valve or
valve gasket, a weak or broken spring, or wear in the
drive linkage. If the operator chooses to repair the
pump rather than install a new one, the use of a
complete repair kit is recommended- Gasolinediluted
oil may indicate a faulty fuel pump.
[ warning^ Use care when reassembling and
reinstalling the pump. Improper
parts alignment ormisconnected fuel tines may result
in leaking fuel, creating a serious fire hazard.
Fuel Pump Reconditioning (Figure 21):
1. Remove fuel lines and mounting screws holding
pump to engine.
2. Make an indicating mark with a file across a point
, at the union of the fuel pump bolt and cover. This
mark will assure proper reassembly. Remove
assembly screws and remove upper pump body.
3. Tum pump body over and remove valve plate
screw and washer. Remove valve retainer, valves,
valve springs and valve gasket, noting their posi¬
tion. Discard valve springs, valves and valve
retainer gasket.
4. Clean pump body thoroughly with solvent and a
fine wire brush.
5. Holding the pump cover with the diaphragm
surface up, place the new valve gasket into the
cavity. Assemble the valve spring and valves in the
cavity. Reassemble the valve retainer. Lock in
position by inserting and tightening fuel pump
valve retainer screw.
6. Place pump body assembly in a clean place and
rebuild the lower diaphragm section.
7. Holding mounting bracket, press down on the
diaphragm to compress spring under it, then turn
bracket 90 degrees to unhook diaphragm so it can
be removed.
8. Clean mounting bracket with a solvent and a fine
wire brush.
9. Replace the diaphragm fuel pump rod spring,
diaphragm gasket, stand new spring in casting,
position diaphragm, compress spring and turn 90
degrees to reconnect diaphragm.
10. Hold bracket, then place the pump cover on it
(make sure that indicating marks are in line) and
insert the four screws. DO NOT TIGHTEN. With
the hand on the mounting bracket only, push the
pump lever to the limit of its travel and hold in this
position while tightening the four screws. This is
important to prevent stretching the diaphragm.
11. Mount the fuel pump on engine, using new
mounting gaskets. Connect the fuel lines.
FIGURE 21. FUEL PUMP ASSEMBLY
28

Onan CCK Specifications

General

Cylinders	2
Ignition System	Battery ignition
Fuel Type	Gasoline
Cooling System	Air-cooled
Fuel System	Carburetor
Starter	Electric
Governor	Mechanical
Max RPM	1800 RPM
Engine Type	4-cycle
Bore and Stroke	3.25 x 3.625 inches (82.55 x 92.08 mm)