aprilia
Air-injection 50 cc
Release 00 / 2002 - 09
05 / 02
Chapter.5
4 - Does the starter motor work properly when you press
the starter button?
INJECTION TROUBLESHOOTING
NO
If the starter motor does not start or
turns slowly
- Make sure the battery is charged
- Check battery connections
- Check the electric plant against the
workshop drawing for the SR 50 water-
cooled model (starter motor)
- (Check the earth connection to the starter
motor)
YES
5 - Does the engine start up normally?
Engine flooded: open the throttle crank engine for 10 seconds, then re-start.
NO
(DOUBLE CHECK THE MALFUNCTION BEFORE REPLACING ANY PART)
Make sure the spark plug is clean; clean or replace if necessary
Make sure it produces a spark on ignition.
- General diagnostics with Game-boy
- Check battery voltage
- Replace the spark plug
- Check Plug lead
- Check the ECU. See
“ECU CONTROL”
Check mechanical parts
- Is the compression ratio right? (piston rings,
piston and cylinder)
- Check the Teflon gasket for the air injector to
see if there are any traces of carbon above the
teflon ring and injector casing
- Does the engine sound strange?
- Are the oil guards and bearings in good
condition?
- Has the reed pack been damaged?
- Is the petrol filter clogged? Is it in place?
- Has the exhaust been damaged? Is it clogged?
NO
YES
YES
NO
See “AIR/FUEL CIRCUIT PRESSURE CONTROL PROCE-
DURE”