5

I recently purchased an 81 Suzuki GS450L, my very first bike. I'm not getting a spark. When it dies, it does so silently. No backfire, sputtering, etc.

My first thought was that it had aftermarket handle bars and it might have an issue in the emergency cutoff, but that should result in no power being sent to spark plug. That isn't what is happening.

My testing so far has consisted of the following.

  • I took a spare spark plug and grounded it to the engine block.
    • I'm getting no visible spark.
  • I used a non contact voltage detector and connected it to the spark plug wire.
    • It shows a series of evenly spaced pulses as I try to turn the engine over, as would be expected.

When I have time later tonight I'm going to use my multimeter to determine exactly what kind of voltage / amperage I'm getting at the plug.. What else should I be looking at / considering?

  • Are you sure the spare spark plug is good? Sounds like it is grounding out to me. – Pᴀᴜʟsᴛᴇʀ2 Mar 14 '15 at 1:01
  • You might have an intermittent leak (exposed wire) in the main electrical lead. Give a visual check of the main lead wires (especially where it comes close to hinges/exhaust surface, etc). Next, what does the plug look like? Is it burning deep grey with a clean smell, or is it black and grimy or white and dusty? Good clues there if you can check the spark plug. Also, it can be very difficult to see the spark in daylight hours, especially is the plug electrode is close. – Jongosi Mar 15 '15 at 0:57
1

I'm not sure if it is everything, but it looks like I had some kind of short (vs break) in one of the ignition coils. My multimeter confirmed this, as did my sense of smell.. Burning plastic is never a good sign, especially under the gas tank.

When I pulled that coil the other side started getting a regular spark. Now I'm off to find a set of aftermarket coils.

  • It may not be a coil issue. Use the good coil on both low voltage leads to see if you get a spark. Take the suspect coil and attach to the other coils low voltage and see if you get a spark, independently. I have seen this issue, exactly as you describe. The problem was the ignition unit or ECU. Not to scare you, it's more likely a coil is bad. Just providing a heads up for you to troubleshoot a bit more to ensure you don't waste any money on an unnecessary component. Best of luck! – DucatiKiller Mar 19 '15 at 5:29
  • @DucatiKiller agreed. My multimeter shows definitely that o one of the coils is out. The ecu and stator will be my next stop if needed. – Tim Brigham Mar 19 '15 at 11:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.