22 Series 4180 Powerhead
: Remove the flange.
: Examine the metering diaphragm 
and sealing ring. Replace if 
necessary, b 6.2.4
Reassemble in the reverse 
sequence.
– Remove the flange, b 6.2.3
: Remove metering diaphragm (1) 
and gasket (2) from the 
carburetor body.
If the gasket and diaphragm are 
stuck together, separate them 
carefully.
: Check the diaphragm and gasket 
and replace if necessary.
The diaphragm is the most delicate 
part of the carburetor. The 
diaphragm material is subjected to 
continuous alternating stresses and 
eventually shows signs of fatigue, 
i.e. the diaphragm distorts and 
swells and has to be replaced.
Reassemble in the reverse 
sequence.
: Place the gasket (1) on the 
carburetor body.
The cutout in the gasket (2) must 
line up with the compensating bore 
in the carburetor.
: Place the metering diaphragm (1) 
on the gasket.
The cutout in the metering 
diaphragm (2) must line up with the 
compensating bore in the 
carburetor and the gasket.
Assemble all other parts, b 6.2.3.
6.2.4 Metering Diaphragm