Yamaha MM700A, Manual, Page: 131 / 282

Five
Fuel Exhaust Systems
The fuel system consists of the fuel tank, fuel pump,
carburetors and air box. There are slight differences
among the various models and they are noted in the vari-
ous procedures.
The exhaust system consists of an exhaust pipe assem-
bly and a muffler.
This chapter includes service procedures for all parts of
the fuel and exhaust systems. Refer to Chapter Three for
information concerning high-altitude tuning.
Carburetor specifications are listed in Table 1 and Ta-
ble 2 at the end of this chapter.
AIR BOX
Periodically inspect the air box (A, Figure 1, typical),
sometimes referred to as the air silencer, for cracks or de-
bris buildup.
CA UTION
Never run the engine without the air box in-
stalled. Running the engine without the air
box causes a lean fuel mixture and engine
seizure. The air box must be installed during
carburetor adjustment.
1. Open the shroud.
2. Remove the air filter element (B, Figure 1, typical).
3. On models with cables routed over the air box, move
the throttle and starter control cables away from the air
box.
4.
Remove the mounting bolts for each ignition coil and
move the ignition coils out of the way.
5. Remove the ignition module mounting screws and
move the ignition module out of the way.
6. Remove the carburetor heater valve mounting screws
(C,
Figure 1) and move the valve out of the way.
7. Loosen the air box intake hose clamps (D, Figure 1).
8. Remove the air box retaining bolt near the steering col-
umn shaft and remove the air box.
9. Cover the carburetors to prevent dirt or moisture from
entering.
10. Installation is the reverse of the preceding steps.
Make sure the rubber intake tubes properly fit onto the
carburetors and the air box.
Inspection
Check the air box for cracks or other damage. Repair
cracks before reinstalling the air box onto the engine.