Today I finished up the six-month odyssey which was the general fix-it-up process for a '69 GS 400 I bought in the fall of last year. One of the things I did was to swap out the points for a Pertronix kit, along with a new coil. I go to start it today and while it'll turn over forever, it won't start. I figure that I have air and gas (clear fuel filter), so it's a spark issue. First, how do you actually check spark? I've cruised the other threads and there's no specific instructions (one guy had a reference to a screwdriver) and I'd prefer not to shock myself. Second, anything else you think I should check? I didn't remove the distributor or do anything else significant to the wiring. Any help is greatly appreciated. Thanks. John
A simple way to check for spark is to find a good "test" spark plug and connect one of the spark plug wires to it. Make sure the steel portion of the test plug is touching bare metal or some other good electrical ground. When cranking, you should see sparks jumping the gap of your test plug. A 12V test light can also come in handy for verifying power to the ignition coil, etc. Devon
You can pull the coil wire and hold it close to clean metal. Have someone crank it and check for spark. If you have spark, the Pertronix is working. No spark, check Pertronix connections and make sure the ground wire in the distributor is good. If you have spark,go on to the spark plug test. A weak battery and/or a corroded battery cable will spark the coil, but not have enough volts to jump the secondary system(cap,rotor,wiring,plugs). Good luck.
I tried the advice posted here - got a spark from the coil (not huge, but I guess I don't have anything to compare it with). That sort of figures since there's a new battery in it and the battery cable seems to be okay. There's no spark at the plug, which suggests to me that there's an issue with the rotor and/or cap. I figure I'll pick up replacements tomorrow and see if that resolves the issue. It looks like the rotor may be sitting a little lower with the Pertronix ring as its base rather than it was - anybody have this problem? I figure I can try to shim it up a little bit and see if that'll make it work. Thanks for any additional advice! John
If you set up the Pertronix with the proper air gap and distributor end play, you should be ok. Additional thoughts, check battery cables if the ends are not factory crimped. Also check for ground wire from negative cable to body and engine to body ground wire. Good luck:beer
You know, when putting my car back together, I totally overlooked this. There used to be a ground cable from the engine to the firewall. I never put that back on, but I ran fine without it. Is there a picture closeup someone has so I can reinstall it?
