Having Spark Problems By leesnitz (Read 375 times)

[leesnitz]

I have a 2008 NST 260 cc scooter that has an interesting spark problem. When I press the start button the engine will start to fire, but as soon as I release the start button it will not stay running. I removed the spark plug and created a temporary ground for it so I could monitor the spark as I crank the engine and here's what I found: the very first spark is bright, every one after that is either extremely week or non existent. When I release the start button, and they key is still in the on position, the plug will still continue to spark (or attempt to) with a very weak spark gradually diminishing to a non existent spark, however when it is non existent, I can still hear the plug trying to arc.  As soon as I turn the key off, or engage the kill switch, it will stop, but often times when I turn the key back on (without hitting the starter button) it will resume.

any ideas?

thanks,
Lee

[richardthescooter3]

Hi leesnitz,
First by pushing the start button your allowing electric circuit to go through your starter relay which turns starter, which start the engine, once the engine is started you don't need the starter button, if its continues to crank, you may have a bad starter.

[fflintstone]

Welcome leesnitz,sounds like it is not the starter with a problem,altho it can be anything at this point--hey richardthe scooter---looks like he can release the starter ok,but it just don't get any spark after initial contact--could be a relay,loose contact,stator going bad,CDI gone bad...these come to mind first--see if you can check these items first--good luck,and some other real techs will be in here soon to look at the problem...JR alleyoop knows how to fix it ,no doubt--happy trails,fflintstone

[alleyoop]

OK, if you release the brake and start button and the STARTER keeps spinning the SOLENOID is stuck and keeping on sending 12 volts to the starter. So if that is the case you need a NEW SOLENOID, to stop it give the SOLENOID a whack on top to disengage the contact inside.

Also regarding the spark DID YOU BY CHANCE change the stator or mess with the wiring from the STATOR?
If so check the WIRE going to the TRIGGER SIDE of the CDI, you may have the wrong wire from the stator plugged into the connector going to the Trigger Port on the CDI.
Alleyoop

[richardthescooter3]

Your right fflinstone, just the way he was describing the action there I thought the starter wasn't shutting off, yeah could be a loose connection on the relay or maybe CDI gone bad, you know it could even be a bad coil, If I was him I check and make sure the coil was tight at both ends and also at the spark plug cap and check the spark plug cap out too, a couple years ago I had a similar problem, stop somewhere for gas and my scooter did not want to start, turned out to be a loose spark plug cap.

[leesnitz]

Hey guys thanks for the help. No, the starter and solenoid are both functioning properly, and none of the stator wires have been messed with. But I did some other testing over the weekend and came to the conclusion that the CDI is bad so I ordered on on line.

I can't think of any other reason it would be generating spark without the stator moving.

[ellpee]

I'm just a tailgater on this thread, have no good answers to offer, but I am thoroughly confused by the descriptions of what is happening. Assuming all is working as intended, hitting the start button energizes the solenoid, allowing 12v to flow to the starter. Starter cranks the engine, which among other things causes the stator to turn and send A/C voltage to the R/R. Somehow, and this is the part where I am even more clueless than usual, the stator also sends some kind of signal to the CDI that says "make a spark!" CDI does whatever it does, and as a result the coil sends a high-voltage pulse to the spark plug which results in a spark.

So if one releases the start button, and the starter stops cranking, and the engine does not "catch" and therefore also stops cranking, I don't understand how weaker and weaker sparks could continue to flow to the plug. It may be that I'm just misunderstanding what posters are saying ...

[richardthescooter3]

It is confusing in the way that leesnitz describes what happens as he pushes the stater button, if like he said that it was still spinning the starter, then alleyoop is right, but he said it was the CDI You got me

[alleyoop]

Well if he is saying that he is getting spark and it is just sitting there not running and the stator is not turning then HE HAS a DC cdi which is fed 12V with the KEY ON and so in that case it would be the CDI that is bad.
Alleyoop

[richardthescooter3]

Thanks alleyoop, I'm not confuse anymore

[fflintstone]

Hey richardthescoot,we always confused anyhow--so,I guess we feeling normal-lol ,happy trails,fflintstone