Fault Finding - Rotax Leonardo 120 Workshop Manual

Fault finding

Below is a list of possible problems, with brief details of the required remedies.
DEFECT
Engine won't start or starts
with difficulty
Engine runs badly when idling
Engine runs badly at high revs
Engine pings under load
20 - 2001
POSSIBLE CAUSE
faulty cylinder head gasket
faulty fuel pump
no petrol in carburetor
valve clearance too small
worn valves or valve guides or imperfect valve seats
worn piston rings
worn cylinder bore
gap between pick-up and rotor too large
loose spark plug
starter motor doesn't turn engine or works intermittently
dirty or wet spark plug
faulty ignition system
faulty ignition coil, spark plug lead or ground lead
short circuit on ignition circuit
valves vorn, or damaged valve seats
CO content too low at idling rate
carburetor hose not hermetically sealed
spark plug gap to wide
dirty carburetor
spark gap too small
insufficient voltage from ignition coil
incorrect valve timing
air leaks in the induction system
spark plug with incorrect thermal rating
petrol octane rating too low
REMEDY
replace gasket
check working order
check float level
adjust valve clearance
replace valves, valve guides, regrind valve seats
replace piston rings
replace cylinder
adjust gap
tighten spark plug
check battery
clean or replace spark plug
check rotor, stator and control unit and replace faulty component
replace
check circuit, check engine stop switch or stand switch
replace valve guides, regrind valve seats
check carburetor and jets, adjust idle rate
replace carburetor hose
replace spark plug or set gap correctly
clean jets
replace spark plug or set gap correctly
replace coil
check timing gear stroke
eliminate any leaks
install spark plug with correct thermal rating
use petrol with specified octane rating
TYPE 120/154/177