How do I check for a good spark?

[John Lapic]

I have a 1971 Johnson 9.5 and just finished replacing points, plugs and condensor. I checked to make sure I got spark by grounding the plug to the block and pulling the starter rope. One coil put out a bright spark, The other sparked but clearly not as bright. I used the same plug for each test. Is there a way to check for acceptable spark? I don't have a spark tester. Can I test the coil some other way? I seem to remember a post a while ago that talked about making a tester with a couple nails but I can't find it.

 

[BaileysBoat]

Re: How do I check for a good spark?

Why not get a spark tester, cheap, and you'll have it forever.

http://www.sjdiscounttools.com/otc7230.html

 

[Mas]

Re: How do I check for a good spark?

Yes...a spark gap tester. You should be able to get them at any auto parts store. Make sure the type you buy has an adjustable gap. What you want to test is how large a gap the spark will jump...not just if it has spark.

MAS

 

[tashasdaddy]

Re: How do I check for a good spark?

agree^^^^

 

[F_R]

Re: How do I check for a good spark?

Also agree. But if you want to make a el-cheapo spark tester, cut the side electrode off a spark plug and use it the way you are already doing. Not the right way, but better than nothing. The gap on an intact spark plug is too close to be of much value as a tester.

 

[tashasdaddy]

Re: How do I check for a good spark?

this works very well.