29Series 4180 Powerhead
The diaphragm pump draws fuel out 
of the tank and into the carburetor 
via the fuel hose. 
Any impurities mixed with the fuel 
are retained by the pickup body 
(filter). The fine pores of the filter 
eventually become clogged with 
minute particles of dirt. This restricts 
the passage of fuel and results in 
fuel starvation.
In the event of problems with the 
fuel supply system, always check 
the fuel tank and the pickup body 
first.
Clean the fuel tank if necessary, 
b 6.6.1.
After completing servicing work on 
the fuel system:
– Test the fuel system for leaks, 
b 6.5.1
: Unscrew the filler cap (1) and 
drain the tank.
– Pour a small amount of clean 
gasoline into the tank and shake 
the unit vigorously.
– Open the tank again and drain it.
Dispose of fuel properly in 
accordance with environmental 
requirements.
Depending on the type of fuel tank, 
two different fuel supply systems 
are installed:
One-part system (molded hose), 
grommet and hoses are in one 
piece. 
Multi-part system, connector and 
hoses are available as separate 
items. 
Differences in removal and 
installation procedures are 
described below.
– Pull the fuel hoses off the 
carburetor, b 6.2.2
One-part system
: Carefully pry the grommet (1) out 
of the fuel tank, taking care not to 
damage the tank.
: Pull the fuel hoses with pickup 
body out of the tank.
6.6 Fuel Supply 6.6.1 Cleaning the Fuel Tank 6.6.2 Fuel Hoses and Pickup 
Body