Home › Forum › Ask A Member › New coils no spark 1956 15 hp evinrude › Reply To: New coils no spark 1956 15 hp evinrude
These guys know what they are talking about. But I say you have dirty points. Or way out of adjustment. You say you set them with a meter—does that mean you have the timing fixture? Doesn’t sound like it. But simply gapping them at 0.020″ is “good enough” for a one-time job.
Once again, dirty points.
Did I mention points?
Coils are OK according to readings you got before installing
That plug wire with high resistance might have a problem.
Um, points??
OK, well I am not going to join this post in mid stream, just adding confusion. I’m a firm believer in the “too many cooks” theory… But, I was captivated by Frank’s comments, I am assuming he is referring to the latest video attachment in this thread. I was so intrigued I decided to devote the ten minutes needed to watch the video from start to finish.
There is a basic error being made while the author is checking that coil with the analog ohm meter….He is using the same ohms scale for both tests. So, he could be getting an inaccurate reading for one or both of the tests.
The low ohms scale is used to test the primary winding, it’s proper resistance is usually a little less than one ohm. So, if the author was using the high ohms scale to test the primary winding, he would never be able to see a resistance of, lets say for example, five ohms… So, if the actual primary resistance of this coil was five ohms, the author would be led to believe he was seeing zero ohms on the meter…. Using the high ohms scale in this instance could miss a primary winding with a relatively high resistance.
The high ohms scale is used to test the secondary winding, it usually has a resistance of several thousand ohms. So, if the author had his analog meter on the low ohms scale while checking the secondary winding, he would be misled into thinking the secondary winding was open, it would have been very hard to see the extremely slight deflection off infinity. So, in this case, the author would have discarded a good coil, at least as far as the secondary resistance is concerned.
Terminology is critical when it comes to reading an ohm meter. Terms like “no reading”, or “nothing” can cause alot of confusion.
All I can say is, please listen to Frank.
OK, just wanted to update my reply a bit….
Again, I try to avoid getting involved in the middle of a thread.
I do share Frank’s frustration with the many online experts that post on youtube etc. I really need to stop watching that stuff, wish there was a way I could block it, shows up even though I have not subscribed.
In this case, as usual, I was a little hasty in my reply.
The video posted by cajuncook/David was just a short video to help the author of this thread, it was not meant to be an instructional video for all viewers. David was responding to a specific question/issue.
Cajuncook/David does a great job with his illustrations/pictures/videos on this site, and his help is greatly appreciated. I wish I had David’s online skills.