Testing Why No Spark

[johnautobus]

could someone explain how to test the stator while still in the shee? I have no spark, so I want to decide if the stator is putting out anything to the cdi box. I know the pickup ciol is ok. I dont know about the coil, but I wanted to start at the begining.. Help would be appreciated.

[bigboybanshee]

If I were you I'd begin testing at the keyswitch, then go to the on/off switch, and then proceed to the stator, CDI, etc. I thought my stator was bad too but come to find out I had a poor connection in the keyswitch that was keeping me from getting spark. If you don't have a clymers manual I highly recommend getting one. The manual tells you EXACTLY what and where to test as well as what to be looking for...

[Guest Yamaha Banshee Rider]

Well, the first thing you can do is disconnect the wires and check them. Ok here is what you should do: Pull the spark plug cap ends off the spark plugs and look in them to see if they are dirty and spray carb cleaner in them and dry them out. Next, disconnect the black and orange wires connected to the ignition coil and look at those to see if they are dirty, clean them too with carb cleaner and dry them off. Next, look at the wire harness going to the back to CDI Box and that small metal box next to it. Disconnect them and spray carb cleanner in those too and dry them off good. When you spray them with carb cleaner, use a rag and wipe them off to clean them reall good. then dry. And after that check your ignition wires, check for splits in the wires. if none, diconnect the wires if you can, and clean them on the connector adaptors. And then check your spark on your spark plugs. They should work after you do all this. because i wasn't getting very good spark on mine and i disconnected these all and cleaned them with carb cleaner and then my spark was a lot better. So do this and see what happens. if it don't work after you do this, pm me and i will try to help you out more.

[Blacksmith]

DO NOT use carb cleaner on the plastic connection of your wiring harness. Many types of cleaner will soften or melt the plastic. In some cases you will get them back together only to never be able to seperate them again.

As for checking out the electrical system the following was posted by BenBB and is really good:

 

 

You really want this bitch to run? Of course you do. Time for a crash course. Here's what you're gonna need:

 

1. A continuity tester; most decent digital volt/ohm meters will have a setting to test continuity, the better ones will emit a tone or squeak when you touch the two test leads together, or when you put the leads on each end of an unbroken wire (you want one with good pointy leads too). You can find these at like Autozone for $20 or so.

 

2. An ohmmeter; again, hopefully the same one as above, capable of reading resistance through a wire (which is measured in Ohms, the symbol is Omega).

 

3. Feeler gauges, well you already got that covered. The matchbook cover method will get you close enough to run.

 

4. I'm sure you got the rest of the normal tools so I won't go there.

 

5. PATIENCE. Maybe 75% of electrical problems are a bitch because they are intermittant; don't give up. Drag the harness in the house, get a box fan for the garage, take a break when you get pissed, whatever. Just take your time and you'll figure it out.

 

OK since you got the harness apart, start with checking continuity through all the wires. Take the 4-wire plug for the stator, find one wire color (like red/white), and then find the same color wire at the CDI connector. Carefully put the test leads on each of the terminals inside the connector and listen for the tester to "beep". If you're not getting any beep first make sure you got the meter set to check continuity and have the leads plugged into the right place on the meter, and you should get a "beep" when you touch the two test leads together.

 

Now check for continuity through all the wires that matter; from the stator (red/white, green/white, red, and green) to the CDI (same colors), from the CDI (black, orange) to the coil, from the CDI (red/black, black) to the key switch, from the CDI (black/white, black) to the handlebar kill switch, and from the CDI (black) to the eyelet ground where the voltage regulator mounts.

 

Don't shove the test leads into the connectors too hard as you can bend the terminals where they won't make contact. It's best if you can set the meter down and hold a test lead in each hand, just making contact against the terminal you're testing.

 

Check that ground eyelet, it needs to have a clean contact to the frame (the voltage regulator itself doesn't matter as it's part of the lighting system).

 

If you find a wire that doesn't have continuity, trace it for cuts or any indications it could be broken. Check the terminal at each end and make sure it's crimped on tight. If there's no physical indication of it being broken and you still get no continuity, trust the meter and replace the wire (more on that later). IF you have continuity in all the places that matter, tape up the harness and move on, that is probably not the problem (this is a good place to just cut off all the TORS connectors, tape the end of the wire so it's not exposed, and then tape 'em all inside the harness).

 

Next, double check the stator & pickup coil resistance. At the stator 4-wire connector, set the meter to read Ohms, and you should have:

Charging coil (red to green wire) 13.7-20.5 Ohms

Pick up coil (white/red to white/green wire) 94-140 Ohms

 

You should be well within those limits with a new stator, but what you really don't want to see here is "infinite ohms" which means there's a break in the wire somewhere. While you're there, just for grins test the ground; set the meter to continuity again and see if it "beeps" going from the single black wire from the stator to one of the bolts on the motor. It should.

 

You got the pickup coil gap set so that is OK, make sure the little phillips screws are tight.

 

Visually inspect the flywheel. You didn't drop it did you? The nut is tight right? If it's loose make sure the little woodruff key didn't fall out or shear off. Check the little magnets on the flywheel with somethin' metal and see if they are still magnetic. Use a wire brush and take off any surface rust.

 

Take a look at the coil and the spark plug leads. Just make sure the leads are attached to the coil and it's not like broken in half. You can test the coil with the ohmmeter but I don't have the specs in front of me (check the Clymer). I had a local mom & pop bike shop bench test my coil fer free so you could do that to get out of the garage.

 

Pretty much all that's left is hooking up all the connectors. Remember what I was sayin' earlier about the terminals, some of them are bent back on themselves to provide tension against the other terminal (this is almost impossible to describe so bear with me), if you shove the test lead in there too hard it can bend it too much and it won't make a good connection. Don't worry, you can remove the little terminals from the connectors and make 'em right. On the inside of the connector, there is a small plastic "tang" that keeps the terminal from coming out the back side of the connector. Use a small pick to push that plastic tang and you can pull the terminal right out.

 

Speaking of connectors, get some dielectric grease and put a nice bead in each of the connectors. If water is your culprit the grease should help.

 

OK so if you haven't found any problems yet, start hooking things back together. For now, just plug in the stator, the CDI, make sure the ground eyelet is tight at the voltage regulator, hook up the coil leads, and nothing else. If the key switch wires are still connected (black/red to black) leave them that way. Don't even hook up anything else (you won't have a kill switch so you'll hafta pull the orange lead off the coil to kill it). Throw fresh plugs in there. Test for spark and/or see if it runs. Does it?

 

If so, plug in the rest of the connecters and check it again. If not, it could be the CDI, since that's all that's left. Do you have your old CDI or can you borrow a buddies (any year) CDI? If you can get ahold of one that works, even if the connectors aren't the same you can give it a try, by removing the terminals (make sure to write down what color wire went where!!) from one style connector and putting them in the other. GOOD LUCK and let us know what it's doing...