Problems Getting Spark (Troubleshooting the newbie)

[Anonymous]

Having been referred here by The Suzuki GRiders forums, and reading your FAQ's, I'm hoping I can benefit from your collective wisdom.

I purchessed an 83' GR650 Suzuki Tempter. After cleaning out the old fule, making sure the lines were not clogged and the engine was going to get fule (It sat for at -least- 5 years prior to my purchess), cleaned the carb's out, cleaning the gas tank, and replacing the -old- nasty oil, we bought a new battery for it and plugged it in. Having spent only $90 for this bike, one in seemingly good cosmetic condition, we gave her a crank.

To much dismay, the engine turned over fine and sounded good, but it would not start. So, we checked to see if the spark plugs were gummed up. After a thorough cleaning, we replaced and gave it a crank. still no start. So, we checked the plugs for spark. Sure enough, the spark plugs are not sparking. So, we came to an impass. Having never owned nor worked on a Tempter before, we are kind of clueless. We replaced the electronic ignition with a certafied used one from a junkyard, and still no spark to the spark plugs.

So, in our ignorance, we think it may be one of a few things. Bad coils? We're not sure how to test the coils, and i don't own a service manual (yet) to test them. After reading all the FAQ's here on The GS Resources, i'm not sure what else to do besides buy a manual and test the electrical system for bad wires?

For a young man only wishing to make his first bike run, does anyone out there have any clue what might be wrong?

Thanx in advance,
-Alex

[Anonymous]

Get a voltmeter and a test light. Test for 12 volts at the coils with the ignition on. Connect the ground of the test light to a spot on the frame or engine and touch the tip to the terminal on the coil from the ignitor and see if it lights up (blinks) when cranking. That should point you in the right direction to find out if it's ignition related or not.

BRAIN FART: I thnk the ground of the test light might need to go to the battery (+) instead. It's been so long since I've done it I can't remember. Can someone verify? Grounding the secondary is what makes the field collapse, right?

[nert]

No, breaking the completed circuit at the coil on the primary side causes the magnetic field to collapse, inducing a current into the secondary windings of the coil that then terminates as a spark out at the spark plug.

With the test light clamp on the battery "-" and the ignition switch on, your test light should lite steady when touching the "+" primary terminal on the coil. If you place the test lite probe to the "-" terminal on the coil and crank, the test light should blink, indicating your points or igniter box is switching to the break or open state of the points, (breaker points), as you are seeing the "+" voltage as it has traveled thu the primary winding and can't go to ground (points open) so it goes through your test lite to battery ground.

Should not matter which battery terminal you have the test light clamp on. If you have the test lite clamp on the "+" terminal of the battery and you crank you should still see the test light blink when at the "-" terminal on the coil. It will blink, because now you will see the closed state of the points or igniter completeing your test light ground.

not very clear was i?

[Anonymous]

not very clear was i?

Ten times better than I was.
Thanks