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No spark

PostPosted: Sun Mar 14, 2021 6:06 pm
by Clarks3
I have a 1953 St Harley-Davidson Hummer that is only getting spark off and on and then stopped, change points and condenser still no spark, check coil still no spark does anybody know what it could be. Thank you

Re: No spark

PostPosted: Sun Mar 14, 2021 7:17 pm
by Bud D
Check to make sure you have electric going to the coil when the switch is on.

Re: No spark

PostPosted: Mon Mar 15, 2021 11:11 pm
by Clarks3
Thank you for your reply I am still a newbie at this would I use a multimeter to do that or better yet how would I do that. And thank you again for your info.

Re: No spark

PostPosted: Wed Mar 17, 2021 8:50 pm
by Bud D
Use a test light on the battery side of the coil and ground.
When the key switch is on it should light.
It's poss. that the switch is faulty.

Re: No spark

PostPosted: Fri Mar 19, 2021 10:38 am
by HarryM
An inexpensive Multimeter/Voltage Tester needed. All reference to tests is with Negative probe to ground (engine is best).
1. Switch off, place a piece of paper/matchbook cover between the contacts of point set.
2. 2. Check battery voltage, anything less than 5.5-volt battery needs charging, if 6 volts activate rear brake lever – brake light ON battery voltage should remain near 6 volt, less than 5.5 volt battery too weak.
3. Switch ON read voltage at both Coil terminals should read (6V). If no voltage on one terminal Coil bad also no voltage would be found in the next step.
4. Check voltage at moving contact of point set. (6V) (Stationary contact is Ground).
If all this is good you should have spark. When removing paper from contacts use it to polish the contacts.
System operation: Voltage from battery through Switch to Coil to Point Set with contacts closed, when contacts open Rapidly the magnetic field generated in the coil collapses inducing a high voltage to the Spark Plug Wire/Plug.

Re: No spark

PostPosted: Mon Mar 22, 2021 8:12 am
by Clarks3
Thank you very much for your information.

Re: No spark

PostPosted: Thu May 06, 2021 11:51 am
by 250_Sprint
Let us know if you have spark.

Re: No spark

PostPosted: Sat May 29, 2021 12:47 pm
by Clarks3
Hello I just wanted to let everybody know I found my no spark problem.
It was located on my points there are two washers one on the top and one on the bottom they appear to be a thick paper washers I did not have those in the right position so my points condenser and the ground wire were all grounding together which had a no spark effect.
Thank all for your info.