moped wont start!!

I have a 1974 piaggio vespa ciao, and it doesnt want to start!! i put new parkplug, i cleand the carb, i tryed bum starting it, but even that didnt work. anyone wana drop me some tips??

Re: moped wont start!!

Get the points checked and make sure you're getting spark out of that new "parkplug" lol.

To test this, take the plug OUT of the head, plug it into the plug wire and hold the threaded end of the plug against the fins of the head... do not bridge the gap between the point and the conductor or else it wont work... Then, crank the motor to see if your plug is sparking.

A bright purple/blue spark is what you should be seeing... If it's dull/dim your points may be failing. In this case you will need to remove the timing cover, and check the gap and condition of the points. These are located inbetween the spinning flywheel and the stationary coils. if there is a lot of corrosion, use a fine grit sandpaper to shine the surface of the flywheel. This will give you better conductivity.

if this does nothing for the spark.. you may need new points all together....

NEXT: if you ARE getting good spark, look at the plug and see if it's wet or dry. If it's dry try squirting some fuel into the head combustion chamber via the spark-plug hole, throw the plug in and crank it... if you get combustion then you have a fuel problem... check your float and the ports in your carb, then check the fuel lines for any kinks or cloggs.

If your plug is WET blow it off, turn the fuel off on the petcock and try cranking it over again. Your carburator may be flooding the cylinder due to a faulty float or some other reason.

between each trial/error start be sure to click the choke on, use half throttle, crank it twice, open the choke and crank it again with no throttle... this way you've got a constant to base how it starts... this is to be sure no human error is involved.

If you try all this and nothing seems to work, bring it to your local small-motor/scooter shop, they should be able to diagnose the problem quickly.

Sorry if this doesnt help :-/

Go nuts.

DannyMoped07

Re: moped wont start!!

A motor need 3 things to run. Air, Gas, Spark.

If you have checked that air intake and found it to be clean then you should be getting air. CHECK

You cleaned the carb and check it for proper flow before putting it back on the motor, right. Then you are getting gas (assuming the tank isn't empty) CHECK

The only thing left is spark. Go down to your local sears and ask for a spark tester. They should know what it is and should have one. (Did when I got mine) basically all it is a item you plug into your spark plug wire then attach the other end to the spark plug then while kicking the bike watch for a spark, if none appear then there is something wrong with the ignition system. Usually best to leave that to the mechanics, as you can quickly screw up a motor if you don't know what your doing. IF you do see a spark then one of the things above isn't making its way all the way through to the engine.

This could be due to a bad valve.

If you want to know exactly how this works go to http://science.howstuffworks.com/two-stroke.htm

Re: moped wont start!!

hey thanks for the help, but where is the timing cover???

im kindov a nuub so dont make fun of me:?

Re: moped wont start!!

It's on one side of the crank-case (motor) Look for 2 wires coming out of the motor, whatever side their on, THAT is the side where the timing cover is. Once you remove that cover, you'll see the fly-wheel and coil.

DannyMoped07

Re: moped wont start!!

don't forget.....some Vespas needed a good taillight bulb or taillight connection to get spark. Check the taillight. It should dimly glow when you kick the engine over. don-ohio

Re: moped wont start!!

BigM it takes 4 things, You got to have exhaust to.

Mike have you even checked for spark?

Re: moped wont start!!

ಠ_ಠ Jon Folks ಠ_ಠ /

I thought it was: fuel(gas+air), spark, and compression.

Re: moped wont start!!

You're correct Brooklyn, those are the things needed for an engine to start. Air is included in the fuel, and exhaust is a biproduct of the starting process.

Re: moped wont start!!

Brooklyn,

"I thought it was: fuel(gas+air), spark, and compression."

Exhaust is also very important. Very!

Rob

Re: moped wont start!!

If you have 0 or close to 0 exhaust flow it will not start ,trust me.

on a 4 stroke

the piston goes down drawing in the fuel and air

then the piston comes up compressing the mixture

and then pow you have spark{at the right time} on the power stroke as the piston goes down

and then the piston comes up forcing out the spent gases out the exhaust.

on a 2 smoke it does it in only 2 strokes but just the same

If you do not have all 4 it will not run or start period. You could almost stretch it a little and say 5 , ignition timing, but that falls in the power stroke.

Are you still there mike? does it have spark

Don O is right on about the tail light issue.

Re: moped wont start!!

Jason Luther /

you need someone to peddle, thats 6

Re: moped wont start!!

not if you have a starter on board

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