PIAGGIO USA, Inc. Training Material for Vespa ET2/ET4 INDEX
FAULT FINDING....................................................................................................................... 3
SYMPTOMS. ................................................................................................................................................................3 POSSIBLE REASONS. ...............................................................................................................................................3 TESTS. ..........................................................................................................................................................................3 Choke staying on. .................................................................................................................................................3 Carburetor flooding. .............................................................................................................................................3 Faulty vacuum tap. ..............................................................................................................................................3 Air filter clogged....................................................................................................................................................3 AUTOMATIC CHOKE OPERATION ................................................................................................ 4
OPERATION .................................................................................................................................................................4 Vespa ET2 50cc engine. .....................................................................................................................................4 Vespa ET4 1 5 0cc LEADER engine. ..................................................................................................................4
FAULTS .........................................................................................................................................................................4 To check if the choke unit is operating. ..........................................................................................................4 Diagram 1 – Choke unit operation ........................................................................................................5 To check the choke circuit. ................................................................................................................................5 Diagram 2 – Choke unit power supply. Vespa ET4 ...........................................................................5 Diagram 3 – Choke unit power supply. Vespa ET2 ...........................................................................6 Diagram 4 – Checking carburetor fuel level .......................................................................................6 150cc L.E.AD.E.R. Engine......................................................................................................... 7
IGNITION, CHARGING & IMMOBILIZER ................................................................................................................7 Ignition. ...................................................................................................................................................................7 Immobilizer. ...........................................................................................................................................................7 Indicators. ..............................................................................................................................................................7 Choke unit. .............................................................................................................................................................7 Carburetor choke. ................................................................................................................................................7
TESTING. ......................................................................................................................................................................8 Immobilizer. ...........................................................................................................................................................8 Examples. ...............................................................................................................................................................8 Stator. .....................................................................................................................................................................9
Vespa Assistenza
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CDI. ..........................................................................................................................................................................9 HT Coil.....................................................................................................................................................................9 WHAT TO DO IF YOU NEED TO CHANGE AN ET4 LOCK BARREL..................................................... 10
IF YOU DO NOT HAVE THE ORIGINAL RED KEY: ............................................................................................. 1 0 IF YOU HAVE THE ORIGINAL RED KEY: ............................................................................................................. 1 0 L.E.AD.E.R. 150cc IGNITION / CHARGING................................................................................... 11 ET2 CHARGING CIRCUIT ......................................................................................................... 12 ET2 & ET4 FUEL GAUGE SENDER AND CIRCUIT ......................................................................... 13 L.E.AD.E.R. 150cc ENGINE SECTION ........................................................................................ 14 VESPA ET2 CRANKSHAFT COMPONENTS (Range 3.9)................................................................. 15 ET2 / 4 SPECS. CHART ............................................................................................................ 16 ASSISTENZA TECHNICAL INFORMATION BULLETIN S................................................................... 17
NUMBER 001, OCTOBER 2 0 0 1 .......................................................................................................................... 1 7 Vespa ET4 sealed battery ............................................................................................................................... 1 7
NUMBER 002, OCTOBER 2 0 0 1 .......................................................................................................................... 1 8 Vespa ET2 & ET4 carburetors ........................................................................................................................ 1 8 ET2 Carburetor Problems .......................................................................................................................... 1 8 ET4 Carburetor Problems .......................................................................................................................... 1 9
NUMBER 003, OCTOBER 2 0 0 1 .......................................................................................................................... 2 0 Programming ET4 immobilizer system ........................................................................................................ 2 0
NUMBER 004, DICEMBER 2 0 0 1........................................................................................................................ 2 2 Vespa ET2 spare parts catalog update ........................................................................................................ 2 2
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FAULT FINDING ENGINE RUNNING RICH
S YMPT OMS . • • •
Vehicles will not start or has cut out and will not restart - The plug is found to be very black and fouled. High fuel consumption - The plug is found to be very black and fouled. Black / badly carboned spark plug.
If you see a black plug satisfy yourself that it is due to excess fuel. • • •
Thick black sooty build up = excess fuel. Black and obviously oily = Oil pump setting. Black and shiny, as if it has been polished with shoe polish = weak spark.
If the plug looks wet but you cannot tell if it is gasoline or oil remember that gasoline will evaporate, oil will not.
POSS IBLE REASONS . • • • •
Choke staying on. Carburetor flooding. Faulty vacuum tap. Air filter clogged.
TES T S . Choke staying on. Remember that the choke defaults to ON. Refer to the information below about testing the choke to answer these questions: 1 . Is the choke getting power when the engine is running? 2 . Is the choke unit working? Carburetor flooding. Refer to the information below to understand the test for fuel leve l. 1 . Is the fuel level reasonable with the engine idling? 2 . Does the level begin to drop when the engine is run at high speed for a period? Faulty vacuum tap. If the diaphragm in the vacuum tap is split then fuel can be sucked down the vacuum pipe and into the manifold. Remove the vacuum pipe from the tap. If the pipe is wet inside the tap must be faulty. Air filter clogged. It is unlikely that a reasonably new vehicle will have a clogged filter but is worth checking if you are running out of ideas. A high mileage vehicle may have collected a lot of dust that is clogging the element. Replacement is probably the best solution.
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AUTOMATIC CHOKE OPERATION The automatic choke units used on Vespa motor scooters are both basically the same and both work in the same w ay. Remember that the choke defaults to being ON so it is unlikely that a cold starting problem is due to a malfunctioning choke.
OPERATI ON • •
• •
The choke unit has a plunger that is pushed down to close off a hole at the bottom of a drilling in the carburetor. A wax pellet is heated electrically and expands, as it heats up it pushes out the plunger. As the wax warms the electrical resistance measured across it increases until it becomes open circuit. In most circumstances the choke will then remain off purely by the heat of the engine. The time taken for the choke to turn off is controlled only by the rate at which the wax expands. The ambient temperature will affect the time taken for the choke to turn off. The choke is activated once the engine has started and not when the ignition is turned on.
Vespa ET2 50cc engine. These motor scooters have headlights that are run from 1 2 volts AC. 12 volts AC is used to operate the choke. AC can only be supplied when the engine is running so the choke cannot begin to turn off until the engine is running. Vespa ET4 150cc LEADER engine. ET4 employs a relay so that the choke will be powered by DC but is triggered by the AC supply when the engine starts.
FAUL T S The most likely choke fault is the choke remaining ON. Symptoms will be anything that may be caused by a rich mixture. 1 . High fuel consumption. 2 . Black spark plug. 3 . Rough running when hot. OK when ridden hard but rough and four stroking at 20 mph. 4 . Fails to start. Plug is found to be black and fouled. To check if the choke unit is operating. Refer to diagram 1. 1. 2. 3. 4. 5. The
Remove choke unit from the carburetor. Measure the distance the plunger is protruding from the body, when it is cold. Attach a 1 2 Volt battery to the socket and leave it for two or three minutes. The plunger should have extended by 4 -5 mm. Disconnect the battery. plunger should retract slowly over a couple of minutes.
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Diagram 1 – Choke unit operation
To check the choke circuit. Refer to diagram 2 for ET2. Diagram 3 for ET4 1 . Follow wire from the choke unit until you find a grey two-pin plug and socket. Unplug. 2 . Resistance check will confirm continuity through the choke unit. 3 . To prove the choke circuit. Connect a voltmeter across the two pins of the socket. With the engine running you should have system voltage. If no voltage then the choke will not turn off. Note . Remember that the choke defaults to being ON. If the choke does not turn off the symptom will be a black and fouled plug. Or; the scooter starts and idles ok and runs at speed ok. When riding slowly (2 0 mph) the engine runs very roughly and four strokes badly.
Diagram 2 – Choke unit power supply. Vespa ET4
Note . Choke units all look much the same but are different and it is important to use the correct choke in the correct carburetor.
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Diagram 3 – Choke unit power supply. Vespa ET2
Note . Choke units all look much the same but are different and it is important to use the correct choke in the correct carburetor.
Diagram 4 – Checking carburetor fuel level
If you find the float bowl only half full then the engine will run weak and may be hard to start.
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150cc L.E.AD.E.R. Engine I GNITI ON, CHARGI NG & IMMOBI L I ZER Use these notes in conjunction with the circuit diagram The electrical system on the new Leader engine is very different to previous two stroke and four stroke Piaggio engines. The ignition, charging & immobilizer circuits do not function in the same way and do not share common components with previous versions. • Ignition is now using the battery circuit. Everything shares one common supply. • Alternator has three phase (all yellow) and ignition pick up coil (green) outputs only. • Rectifier / Regulator is very simple. Three phase (yellow) inputs and one (red / blue) output. • CDI unit has become more complicated. The one unit is responsible for; ignition, immobilizer, indicators & choke unit. Ignition. When the ignition is turned on power is supplied to the CDI via the orange wire (terminal 5). Ignition pick up is via green wire (terminal 2). Output to the HT coil is via purple wire (terminal 3). The unit is earthed via black wire (terminal 8). Immobilizer. The wires connected to the unmarked terminals are from the antenna that is mounted around the ignition lock barrel. The red / blue wire (terminal 4) supplies battery voltage even with ignition off. Yellow wire (terminal 6) supplies the LED on the instrument panel. This LED should be flashing with the ignition turned off to confirm that the immobilizer system is functioning. See the notes below about using the LED for immobilizer fault finding. Indicators. There is no separate indicator relay. The relay function is contained within the CDI unit, Power to the indicator switch is via the blue / black wire (terminal 1). Choke unit. The choke is now controlled by the CDI (not the regulator). Power is supplied to the choke via the orange wire when the ignition is turned on. The unit will not function until the engine is running when the CDI will complete the circuit to earth via the white / black wire (terminal 7). Carburetor choke. The carburettor heater will start working as soon as the ignition is turned on. Power is supplied via the orange wire.
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TES TI NG. Immobilizer. • • • • • •
Normally use the blue key for testing. The diagnostic test socket is on the right hand side and will be seen once the helmet storage compartment is removed. Use the exiting test box in this socket. Testing can be done by using the instrument panel mounted LED. If the system is working normally the LED will be flashing when the ignition is off and it will stop flashing when the ignition is on. If the immobilizer system is faulty, when the ignition is switched on there will be a series of flashes. The flashes hold a key to the fault.
1 . The first flash will be long (2 seconds) or short (0.7 second). A Long flash means the CDI is not programmed. Short flash if the CDI is programmed. 2 . Next is a series of short (0.5 second) flashes. 1 flash = CDI not grounded 2 flash = No transponder detected. Fault with Key or antenna. 3 flash = Transponder detected but not recognized. 4 flash = System not programmed. 3 . The last thing to notice is whether the LED finally remains on or off. OFF = Ignition is possible. ON = Ignition is not possible. Examples.
1
2
3 LED off
2 sec
CDI not programmed. Engine will run up to 2000 rpm 2 sec
2 x 0.5 sec
LED off
CDI not programmed. Key transponder not detected. Fault with transponder or a erial. Engine will run up to 2 0 0 0 rpm. LED off
0.7 sec
CDI programmed. System function normally. 0.7 sec
2 x 0.5 sec
LED on
CDI programmed. Key transponder not detected. Fault with transponder or aerial. Ignition not possible CDI programmed. Key transponder detected but not recognized. Ignition not possible
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Stator. Any yellow-to-yellow should give continuity. Yellow to ground should not give continuity. CDI. Note that the ET4 Leader and ET2 use different CDI units. CDI Unit connections -
Antenna
-
-
-
Antenna
6
Yellow - diagnostic LED control
1
Black / Blue - Output to indicator switch (1 2v switching on / off)
8
Black - Ground
3
Purple - Output to HT coil
4
Red / Blue - input. Battery voltage even with ignition switched off.
5
White /Red - input. Battery voltage only with ignition on.
7
White / Black - input from choke. To ground only when engine is running.
2
Green - input. Pulse from ignition pickup.
HT Coil. • •
Purple to Black - primary winding HT to Black - secondary winding
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WHAT TO DO IF YOU NEED TO CHANGE AN ET4 LOCK BARREL IF Y OU DO NO T HAVE T HE OR I G I NAL RED KEY: If you do not have the original RED key then the only solution is to change the Immobilizer and CDI unit as well.
IF Y OU HAVE T HE OR I GINAL RED KEY: 1 . Order a lock barrel set p / n: 5 7 3 4 3 0. This is supplied with a pre cut RED k ey. 2 . Order a BLUE key p / n: 5 7 3 4 2 6. 3.
Fit the new lock barrels.
4 . Remove the flip up transponder from the OLD RED key by separating the two halves of the key slightly with a screwdriver. Do the same to the NEW RED key and then fit the OLD transponder into the NEW key. Now the immobilizer system will function as normal (It will not know anything has changed). 5.
Get the new blue key cut and then program it in the normal way.
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L.E.AD.E.R. 150cc IGNITION /CHARGING
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ET2 CHARGING CIRCUIT
Note: oil light remains alight for 15 seconds after turning ignition on • • • • •
• • • •
Alternator stator and control box both have separate components for AC and DC circuits. AC output is full wave and regulated. DC output is half wave rectified and regulated. DC regulation is on negative side of the alternator. If the voltage on terminal 5 is below 8V DC approx. (flat battery) when starting, the DC rectifier / regulator will not function so there will be no output from the alternator on the DC circuit. Connect a booster battery to raise the voltage when starting; this will make the rectifier / regulator function. Choke heater will only begin to operate once the engine is running. (AC circuit) The oil warning light will “self check”. Every time the ignition is turned on the light will come on for 15 second s. These vehicles do not have a separate indicator relay. Tests . 1. Blue / Grey to Ground = 25 – 3 0 volts AC @ 3 0 0 0 rpm. 2. Ammeter between red and battery positive = 1.5 – 2 amps with battery at 1 3 volts
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ET2 & ET4 FUEL GAUGE SENDER AND CIRCUIT
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L.E.AD.E.R. 150cc ENGINE SECTION
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VESPA ET2 CRANKSHAFT COMPONENTS (Range 3.9)
• • • • • •
Crankshaft spline length from shoulder at main bearing to the end is always 7 2.5 mm. The component stack as shown above must be 7 4.0 mm Important. The nut must not bottom on the crankshaft shoulder. Assemble all the components on the shaft without the fan. Check that the splines end 1 mm below the face of the kick -start plate. DO NOT grease variator rollers. Always use a new nut. Use Locktite 2 4 2F or similar and torque to 4 0-44 N.M. by means of the specific half pulley holding tool P / N 0 2 0 1 6 5Y
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ET2/4 SPECS. CHART
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ASSISTENZA TECHNICAL INFORMATION BULLETINS
NUMBER 001, OCT OBER 2001
Vespa ET4 sealed battery It has come to our attention that there were a number of Vespa ET4 scooters that were fitted with acid type batteries from the factory. If you receive a Vespa with the wrong battery fitted please remove the battery and place the VIN # of the vehicle it came out of on it. Please return any wrong batteries that you have collected at the end of the month and bill Piaggio USA for the shipping. Please order a replacement battery on a Pre -Sales order form and fax it to (3 1 0) 6 0 4-3 9 8 9 and we will send the replacement battery to you second day shipment. All Vespa ET4’s shipped after the August 1 9 will arrive fitted with the proper battery. We at Piaggio would like to apologize for this problem and any inconvenience that it may have caused.
Correct battery
Incorrect Battery
1 2V-10A maintenance -free type
Vespa Assistenza
1 2V-12A Acid type
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NUMBER 002, OCT OBER 2001
Vespa ET2 & ET4 carburetors We have noticed an increasing number of carburetor change outs in the Warranty claims. Piaggio USA will not honor the warranty replacement of complete carburetors unless there is a broken part or a manufacturer’s defect. All carburetors that are not functioning properly must be disassembled and properly cleaned and reinstalled before approval to replace the carburetor will be given by the Vespa Assistenza Department. Please see Technical notes below on the symptoms and causes and repair of the ET2 and ET4 carburetors. ET2 Carburetor Problems Symptoms: After PDI the Vespa will not start and gas overflows from the carburetor. Action: In this case the float needle is most likely stuck to the seat in the carburetor (please see picture below). To fix this problem you can remove the float bowl and gently pull the float up in order to release the needle from the seat. Another option is to remove the fuel line to the carburetor and gently blow compressed air into the line thus causing the needle to push away from the seat. If done properly, once the needle is separated from the seat and gasoline is able to pass through the seat the problem should not reoccur.
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ET4 Carburetor Problems Symptoms: Vespa will start and idle but dies as soon as the accelerator is turned. This symptom is very similar to the CDI not being programmed but it will not gain slightly in rpm’s when the throttle is turned, as it will do if the CDI is not programmed. Action: In this case the problem is usually a clogged pilot jet. The idle circuit is running off of the choke jet and this is allowing the scooter to start and idle but as soon as you turn the throttle there is no transition from the pilot circuit to the main jet and the scooter will die. Turn the carburetor over and remove the four float bowl screws (A). Remove the jets (B) as pictured below and clean the carburetor and the jets thoroughly with carburetor cleaner and a jet pick . Please be careful not to get carburetor cleaner on any of the other engine components as it may ruin surface finishes. After the carburetor and jets have been thoroughly cleaned and the carburetor refitted (c) the running problem should be solved.
A
B
C
W arning: W hen working with gasoline or other harmful chemicals, please be sure to use gloves and proper eye protection and always work in a well-ventilated area and do not work near an open flame or hot surfaces.
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NUMBER 003, OCT OBER 2001
Programming ET4 immobilizer system We have had a few questions lately on how to properly program keys for the ET4. Review the instructions and pictures below to help you program new keys. The red key opens and closes the circuit. All of the un -programmed blue keys should be introduced in between the red keys. You can program up to seven blue keys.
1. Separate the keys and remove all key chains.
2. Put the red key in the ignition.
3. Turn the key to the “on” position.
4. Turn the key “Off” when the LED comes on.
5. Remove the red key.
6. Place the blue key in the ignition within 6 seconds.
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7. Turn the key to the “On” position.
8. Turn the key “Off’ when the LED comes on.
9. Remove the blue key. (Repeat steps 6 -9 for additional blue keys)
10. Put the red key in the ignition within 6 seconds.
11. Turn the key to the “On” position.
12. Turn the key “Off” before the LED comes on.
13. Remove the red key to close the circuit.
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NUMBER 004, D ICEMBER 2001 Vespa ET2 spare parts catalog update On page 2 8, table 7 has been updated to reflect proper part descriptions and part numbers for the items shown within the graph. Please open the document title Table 7 and add a copy to all of your ET2 Parts Books.
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Here's a bit of a checklist of things to look at.....
Engine does turn over but won't start - If the scooter does turn over but still doesn't start you should check for a spark and make sure fuel is getting to the engine. To check for a spark, remove the spark plug from the cylinder and re-attach the spark plug cap/lead back onto the spark plug. Hold the tip of the plug against the cylinder head and crank the engine.
You should see a blue spark across the gap, the spark should be strong! If you don't, there's possibly a problem with the ignition. This could mean that you have a faulty coil, CDI unit or electronic ignition module which will have to be replaced, or it could just be a loose wire. If the spark plug is fouled up/oily/overly blackened then it is very likely that it is the cause of your problems and you should consider replacing it as statistically, the second most likely fault with starting a scooter is a faulty/fouled up spark plug.
If you do have a strong spark, you next need to check that fuel is being delivered to the carburetor. Make sure there is fuel in the tank first and if so you can move on to checking the fuel valve. Most scooters use either a gravity fuel feed by locating the fuel tank higher than the carburetor, or some use a vacuum-fed petcock (on/off tap) controlled by the vacuum created at the carburetor. The carburetor has two fuel-related pipes connected to it. One is from the fuel tank and is for the fuel supply, the other provides a vacuum to suck the fuel from the fuel valve. If you disconnect the fuel supply pipe from the carburetor, fuel should flow out when you crank the engine (be careful to catch the fuel if you do this and don't do it with a hot engine), if fuel doesn't flow out then the fuel valve may be faulty. You can try applying a vacuum to see if fuel flows by sucking on the vacuum pipe(but make sure it's the vacuum line, not the fuel line if you try this!). Another Tip: If there is a spark but you are unsure about fuel supply... squirt a little bit of fuel (a spoonful) into the spark plug hole and then replace the spark plug and try to start the engine.....if it starts and runs for 5 seconds and then dies then you can check for fuel flow to the carb, or blocked jets.
If you are getting a strong spark, fuel supply to the carburetor is good and the engine is turning over on the starter, it's possible that the electrically operated automatic choke has failed. It's supposed to operate when the engine is cold, but if it's stuck or burned out, the mixture will be weak and the scooter probably won't start. The automatic choke is usually a black cylindrical object attached to the carburetor with a couple of wires coming out from it. It's the only electrical powered component attached to the carburetor, so it's usually not too hard to spot. If you have a meter you can measure the resistance across the leads of the choke, you should see around 10 ohms or less. If it's an open circuit its likely to be burned out and will need to be replaced. If it seems to be OK it may simply be stuck, or the wiring to it may have a problem/loose connection. You can also check to see that it's getting voltage across its terminals. A final check...remove the choke from the carb and plug the wires into a 12V source for about 5-10 minutes. The choke body should get warm and the protruding mechanism should extend slightly. Measure the length of the protruding choke mechanism - it should have increased in length by around 5mm more than when it was cold.
It's also possible that there is a problem with the cleanliness of the carburetor and if so you may need to remove it and clean it out. If the scooter has been sitting for a few months with fuel in the carburetor, the fuel may have evaporated and left behind a sticky 'gum' that will prevent the carburetor from working properly and which must be removed. Statistically, the biggest problem for a scooter not starting is a gummed up carburetor/ blocked carb jets.
A very common problem is blocked jets in the carburetor. The jets have tiny holes in them that the fuel passes through to supply the carb and these become gummed up with fuel residue. You will find three jets in the carb (Main jet-used for Wide Open Throttle, Idle Jet-feeds the carb at idle/low revs, Choke/Power Jet-gives extra-rich fuel supply when starting from cold) and its easy to remove the jets and clean them out with a spot of Carb Cleaning Fluid and/or with compressed air. A tip is to blow through the jets with your mouth and then hold them up to the light to see if you can see clear daylight through the jet's bore. Whatever you do don't be tempted to prod the hole in the jet with a bit of wire or a needle as this will enlarge the jet's bore and be the cause of tuning problems at a later stage.
Setting the idle mixture screw - You could also be experiencing too rich or too lean fuel/air mixture to your carb. To set this you should screw the idle mixture screw fully in.... (Before you screw it in...look at where the screwdriver slot is at... then count how many turns it takes to go all the way in gently... 1 and 1/2 turns for example, and remember the number of turns for later)..... then unscrew it out by the number of turns that it states in your handbook - for my scooter it was 1 and 1/2 turns out.
If the automatic choke is problem free, the starter cranks the engine sufficiently, there's fuel at the carb and there's a strong spark then there may be an engine problem and you need to check the cylinder compression. To do this accurately you will need a compression tester. It screws in instead of the spark plug and measures cylinder pressure. When you crank the engine you should see a reading of approaching 125-150 psi. If it's 100 psi or less then its likely that you have an engine problem (probably failed piston rings) and you will need to remove the cylinder head to gain access to the piston rings. A trick to try if you haven't got a Compression Tester is to hold your finger tightly over the spark plug hole with the spark plug removed to see if your finger is forced away strongly when you try to turn the engine over - it may just indicate that there is very little compression if the force is very minor. Another tip is to add a teaspoon of engine oil through the spark plug hole and try to crank the engine again. If you then get a better compression its likely that the piston rings are shot, as the oil you added sealed the rings for a short period of time and hence temporarily gave you better compression.
Hope this helps
Fabio
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