Scooter ran fine for days, then it didn't. Won't start. By helix803 (Read 1,142 times)

[helix803]

I am working on my nephew's friend's TaoTao ATM50. The scooter was running fine, but today it just quit and would not restart. The intake and exhaust valve adjusters were extremely tight. I adjusted both to .004. The engine would still not run. I tested for spark by grounding the body of the plug to the cam cover and saw no sparking while starting. Which part could have failed?

[Alleyoop]

First check the killswitch make sure it is not on also some have a killswitch on the sidestand make sure it is up. Other than that simple stuff you will have to test to see which part is bad.
0. Bad Ground Wire from motor to Frame.
1. Bad plug
2. Bad Boot Cap
3. Boot cap not making good contact with the coil wire(the Boot caps screw onto the coil wire.
4. Bad coil
5. Bad CDI
6. Bad Pickup Coil
7. Bad Stator
Also here is a good VIDEO to test for a NOSPARK.
Alleyoop

[tvnacman]

you need 3 items foe it to run/start. spark, fuel and compression . Check for spark, fuel and compression.

John

[Alleyoop]

Sept 4, 2015 5:11:40 GMT -6 tvnacman said:

you need 3 items foe it to run/start. spark, fuel and compression . Check for spark, fuel and compression.

John

He already SAID he has no spark The culprit for NO SPARK has to be found.

[tvnacman]

tvnacman <----- suffering from head in azz

[helix803]

Excellent video.

I tested the coil resistance like the video said. Where he had 2.8 ohm resistance, mine showed .2 ohm resistance.

I tested the starting AC voltage coming out of the stator and got a reading of 45V AC where he had 75V AC. Is my result out of line?

[tvnacman]

Sept 4, 2015 14:16:20 GMT -6 helix803 said:

Excellent video.

I tested the coil resistance like the video said. Where he had 2.8 ohm resistance, mine showed .2 ohm resistance.

I tested the starting AC voltage coming out of the stator and got a reading of 45V AC where he had 75V AC. Is my result out of line?

You need 35 to 120vac so 45 is good (black/red) look for .5vac on the pulse coil blue/white or blue/yellow.

John

[helix803]

I got around .25 V AC on the pickup wire.

[Alleyoop]

Good the Pickup Coil is good, the stator is good. Do you have a wire from the motor to the FRAME and is that in good shape because if the MOTOR GROUND is bad NO SPARK.
So now we are down to the CDI not putting out or the COIL not putting out or a bad plug and or BOOT CAP.
The wire from the CDI going to the COIL should be 300+volts, the coil you can only test for continuity the Boot Cap you can unscrew it and cut about 1/4-1/2 inch off the coil wire and then screw the Boot cap back onto the coil wire. The boot cap should snap onto the threaded tip of the spark plug and hold nice and snug.
Alleyoop

[helix803]

Spark plug is new.

Trimmed and reattached the plug wire, but now the battery is dead. It won't hold a charge. I keep it on a charger but it just won't hold.

Can't do anything with a bad battery.

[Alleyoop]

Bummer, do you have a car and jumper cables you can jump your scooter battery to continue with your tests.If not then a new battery is in order, get one that is at least 7AMPs and the rating on the CCAs are OVER 100 the higher over 100 the better. The CCAs are the rated cold cranking amps the battery will put out. If under 100 you may get 2-3 good cranks before there is not enough power left to work the starter. So HIGH CCAs on a battery on a scoot is very important, if you notice the cheap batteries will be rated around under 100 ccas, you pay for what you get, a good battery that will give you some cranking power will be rated at 120+ CCAs.
Alleyoop

[tvnacman]

kick start it.

John

[helix803]

Ha, this POS TaoTao has a busted kick-starter.

[tvnacman]

wait for the battery to charge.