Excessive Oil Consumption/Exhaust Smoke; Insufficient Lubrication Pressure; Poor Lubrication Pressure - PIAGGIO 633929(IT) Service Station Manual

MP3 125
Possible Cause
Rpm too low at start-up or engine and start-up
system damaged
Incorrect valve sealing or valve adjustment
Engine flooded
Automatic starter failure
Air filter blocked or dirty.
Faulty spark plug or incorrect ignition advance
The carburettor is dirty; fuel pump or vacuum valve
damaged
Flat battery
Intake coupling cracked or clamps incorrectly
tightened
Defective floating valve
Carburettor nozzles clogged

Excessive oil consumption/Exhaust smoke

EXCESSIVE OIL CONSUMPTION/SMOKEY EXHAUST
Possible Cause
Worn valve guides
Worn valve oil guard
Oil leaks from the couplings or from the gaskets Check and replace the gaskets or restore the cou-
Worn or broken piston rings or piston rings that
have not been fitted properly

Insufficient lubrication pressure

Possible Cause
By-Pass remains open
Oil pump with excessive clearance
Oil filter too dirty
Check the starter motor, the system and the torque
Inspect the head and/or restore the correct clear-
Try starting-up with the throttle fully open. If the
engine fails to start, remove the spark plug, dry it
and before refitting, make the motor turn so as to
expel the fuel excess taking care to connect the
cap to the spark plug, and this in turn to the ground.
If the fuel tank is empty, refuel and start up.
Check: mechanical movement, electric connec-
Dismantle the sponge, wash with water and sham-
poo, then soak it in a mixture of 50% petrol and
50% of specific oil (Selenia Air Filter Oil), then
hand dry without squeezing, allow to drip dry and
Replace the spark plug or check the ignition circuit
Remove, wash with solvent and dry with com-
Check the charge of the battery, if there are any
sulphur marks, replace and use the new battery
following the instructions shown in the chapter
Replace the intake coupling and check the clamps
Check the proper sliding of the float and the func-
Dismantle, wash with solvent and dry with com-
Replace the piston cylinder unit or just the piston

POOR LUBRICATION PRESSURE

Check the By-Pass and replace if required. Care-
Perform the dimensional checks on the oil pump
Operation
limiter
ance
tion and fuel supply, replace if required.
then reassemble.
components
pressed air or replace
are tightened
tioning of the valve
pressed air
Operation
Check and replace the head unit if required
Replace the valve oil guard
pling seal
rings
Operation
fully clean the By-Pass area.
components
Replace the cartridge filter
Troubleshooting
TROUBL - 3