starting problems By rpaulson (Read 2,831 times)

[rpaulson]

my avanti 150cc scooter was running great one second and the just a moment later its spitting and sputtering backfiring and then died no it wont start i started checking basics and there is no spark so here is a little history on it that is all i know a friend gave it to me 2 weeks ago first scooter i ever seen worked on cars a lot but feel lost here so any way you would have to tap on the flasher switch sometimes to get it to start so somethings wrong but it still always ran fine any suggestions or feed back would be awesome was just starting to like the little fella thought if i could wire coil up straight i would do that but i not sure where the coil is looks like wire gois in to the motor by the fan is it like a lawn mower

[JR]

Here is the typical coil and CDI on a GY-6 scooter and here is a diagram of how it all goes together:



Here's the pinout on the typical AC type CDI:



Now since you said you could tap on the flasher switch and it would run I suspect this was the engine kill switch? As you can see you have a engine kill wire to the CDI. The CDI sends voltage to the coil and gets it's voltage from the stator through the red/black wire to the tune of up to 100 Vac.

What I'm suspecting off the bat is bad wire connections, bad kill switch or the engine kill wire is grounding out. The engine is killed when you turn the key off or press the engine kill switch by simply grounding out the CDI thus killing power to the coil thus no spark.

We're here to help and I'll be gone for a spell but check back in later. Time to start searching for bad wires first.

Also Welcome to the forum!

JR

[rpaulson]

i did find the coil i think it has 2 wires going to it one is green with white strip i believe the other is yellow with black strip when the green one is plunged in both sides are a ground the yellow ones is neither ground or a positive well has no voltage the green wire when disconnected is a ground the yellow disconnected has no voltage and if you hook up the green and test both sides of the coil they are bot a ground hope you understand what i am saying

[rpaulson]

that was awesome answer i by the way i should have said that sooner sorry for my bad manners thank you for the help so far

[alleyoop]

Yes the wires going to the CDI get voltage from the Stator so only when the motor is turning over will voltage be sent to the COIL. So just sitting there no voltage will be present.
Alleyoop

[alleyoop]

I do not know if you tried this but Take the KILLSWITCH WIRE off the CDI and see if you then get spark and it fires. In the pictures above you can see WHICH WIRE is the KILL SWITCH WIRE on the CDI.
Alleyoop

[JR]

The CDI is a little black box like above and they put them in various places but they are not far from the coil usually and also always near the engine. Two ways to find it if you just can't see it and BTW you generally have to remove some plastics.

Since you've found the coil trace the yellow/black wire on the one side of the coil and it will go only to the CDI. Just as in the diagram above the typical GY-6 AC type CDI has 5 wires;

yellow/black = feed to coil
green = ground
black/white = engine kill wire
black/red = AC voltage feed from stator
red/white or bluewhite = pick up coil wire.


Other way to locate it is to look at the bundle of wires coming out of the engine, again the AC feed wire to the coil will be black/red, trace it to the coil.
JR

[wheezy]

Oct 18, 2012 19:46:21 GMT -6 rpaulson said:

thanks for the suggestion i have a dumb question whats the cdi and where is it located

JR explained where to find and how to test it, but in simplest terms, a CDI is a capacitor discharge method of triggering the ignition coil. It gets it feed from the stator, so it only produces voltage when the crankshaft is turning.

The kill switch feeds it a ground to shut the engine off. As others have suggested, pull that wire off the CDI, and use a multimeter on the ohms setting to check back through the wire and kill switch.

Place the red lead on the wire, and the black lead on a good ground point on the bike. It should read open (max resistance or OL on the meter) with the kill switch in the run position, and short (very close to 0 ohms) in the kill position. Rattle the switch and wire a bit while in the run position to see if you have an intermittent ground on the wire.

[rpaulson]

ok i found the cdi it was under the hood part it only has 4 wires going to it red green yellow and white is that it

[rpaulson]

it does have a alarm on it to if that makes a difference but no ware in the owners manual does it say anything about a kill switch

[JR]

Oct 21, 2012 4:09:06 GMT -6 rpaulson said:

ok i found the cdi it was under the hood part it only has 4 wires going to it red green yellow and white is that it

No that is the Regulator/Rectifier R/R it deals with charging and has nothing to do with the scooter starting, the CDI will not be up front, could actually be under your seat.

What you found looks probably something like this, it may be black in color too and again it's not the CDI.




The CDI will have 5 wires to it and looks like this:




JR

[JR]

Oct 21, 2012 4:11:36 GMT -6 rpaulson said:

it does have a alarm on it to if that makes a difference but no ware in the owners manual does it say anything about a kill switch

Most scooters have what is called an emergency kill switch on the right side of the handle bars will have a symbol on it like this;



It a lot of times is on the same setup with the start button and/or any other possible switch. The scooter run position is a circle with the arrow and the off position is the circle arrow with a X in it.

JR

[terrilee]

sorry i have NO help for u
starting problems could be so many things.

But i do remember when i 1st got "Chrissy"
and started reading the libraries on all the forums ,
and they were all saying CDI, Coil, Stator, valve gaps,etc, etc etc,
AND I HAD NO IDEA WHAT THEY WERE TALKING ABOUT!! LOL
i was like "what Freaking kind of language is this."

BUT DONT GET DISCOURAGED
you will learn the lingo, find the the different parts
the guys are pointing out.
actually start understanding the weird setups of scoots
THINGS WILL GET BETTER.

i thank the GREAT SPIRIT that i had no real problems,
when i 1st started riding.
i got learn about magnetos a.k.a. stators
CDI's , coils, etc etc by reading other peoples posts
and the probs they were having , and how they were told how to check 'em and fix 'em.

things will get better
good luck
and just think of it this way
if a old woman can learn this.
YOU CAN TOO

[rpaulson]

cool i found it thanks for the kind words and good advice i tried to remove the ground wire and still no spark what to check no once i removed the stash box under the seat piece of cake heck can see everything now the scooter still wont start what should i do next

[rpaulson]

last post on this issues and thank everyone so much for your contributions to this problem it is resolved it was a bad cdi replaced and i have beloved scooter back on the road thank everyone so awesome of a site i am defiantly telling everyone how helpful this site is