15MS 362, MS 362 C
Condition Cause Remedy
Engine speed drops quickly under
load – low power
Air filter dirty Clean air filter or replace if
necessary
Throttle shutter not opened fully Check throttle cable and rod
Tank vent faulty Replace tank vent
Fuel pickup body dirty Install new pickup body
Fuel strainer dirty Clean fuel strainer in carburetor,
replace if necessary
Leak on fuel hose from tank to
carburetor
Seal connections or install new fuel
hose
Setting of high speed screw H too
rich
Check basic carburetor setting,
correct if necessary
Main jet bores or ports blocked Clean the carburetor
Pump diaphragm damaged or
fatigued
Fit new pump diaphragm
Ignition timing wrong, flywheel out
of adjustment, key in flywheel is
missing or has sheared off
Fit key if necessary and secure
flywheel properly or install new
flywheel
Engine running extremely rich, has
no power and a very low maximum
speed
Choke shutter does not open Check the carburetor and service
or replace if necessary.
Engine running too rich, loss of
power and maximum speed too low
Choke shutter does not open fully
in full throttle position
Check the carburetor and service
or replace if necessary.
Erratic idle – too lean Choke shutter does not close
completely
Check the end cover with choke
shutter and replace if necessary
Anti-vibration elements worn Replace anti-vibration elements on
carburetor.