Wacker Neuson WM 80 User Manual

WM 80 Repair Carburetor Basics
wc_tx000522gb.fm 57
See Graphic: wc_gr002893
Start-up mode (choke):
During cold start-up, the choke shutter (butterfly) (k) is closed and the
throttle shutter (l) is partially open. As the engine is turned over, engine
suction draws fuel from the primary (m), secondary (n), and main fuel
(o) discharge ports. Since the choke is closed, the amount of air
flowing through the carburetor is very restricted. As a result, a rich fuel
mixture (fuel mixed with a relatively small amount of air) is delivered to
the engine which allows the engine to start more readily than a lean
mixture.
See Graphic: wc_gr002894
Idle Speed:
At idle speed, only a small amount of air flow through the carburetor is
required. The air flow is regulated by the throttle shutter alone because
the choke is open. However, the throttle shutter regulates the air flow
differently, depending on the version of the carburetor used.
In dual-needle versions (1), the throttle shutter
(p) is adjusted by an idle
speed screw. The idle speed is also regulated by the slow speed
mixture needle valve
(s). By turning the valve, the fuel/air mixture can
be made richer or leaner, affecting the engine’s speed (rpm).
wc_gr002893
n
m
l
o
k

Wacker Neuson WM 80 Specifications

General

Brand	Wacker Neuson
Model	WM 80
Category	Engine
Language	English