Generac Power Systems GTH1000, Service Manual, Page: 19 / 74

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SECTION 3: CARBURETION AND FUEL SYSTEM
CLINCHING
SCREW
IDLE
W
O
T
Figure 3.8.
CARBURETOR INSTALLATION – HORIZONTAL SHAFT
1. Install a new carburetor gasket and carburetor onto the studs.
2. Install air cleaner base, breather tube and EVAP hose (if
equipped), bolt and nuts and torque to 5.4 Nm (48 in. lbs.).
3. Re-attach choke and throttle links and solenoid wire to
carburetor.
4. Install fuel line and fuel line clamp.
5. Install oil fill tube and hold down bolt and torque to 4.7 Nm (40
in. lbs.).
6. Install air cleaner and air cleaner cover.
7. Install yellow knob for Summer/Winter control.
8. Perform a static governor adjustment. (See “Static Governor
Adjustment”, page 4-2)
9. Start engine and allow to warm up for 5 minutes.
10. Move speed control lever to slow speed position and hold throttle
lever against idle stop screw.
11. Adjust the idle stop screw to maintain ~ 1800 RPM idle.
12. Slowly move speed control lever to high-speed position.
13. With the speed control in the high speed position, adjust the high
speed screw to obtain the desired engine speed. Do not exceed
3800 RPM.
FUEL PUMP
The fuel pump supplied with the engine is a pulse type pump. It uses
crankcase vacuum pulses drawn from the valve cover to pump the
fuel. It is capable of priming at 12" (30.5 cm) maximum lift, and has
a maximum outlet pressure of 1.5 psi. If the fuel pump is not working
properly, check the vent hole on the top of the pump for obstructions.
If a fuel pump other than the factory recommended pump is used, the
fuel line pressure at the carburetor inlet must not exceed 3 psi. Pres-
sures in excess of 3 psi may cause an over rich carburetor mixture
that would lead to engine damage.
FUEL FROM
TANK
PULSE LINE
VENT HOLE
TO
CARBURETOR
INLET
Figure 3-9. Fuel Pump
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