inline spark testers

[slomo]

Finally checked my own mowers for spark or proper healthy spark.

See the first line on the far left in the SE or small engine area? Very first one. I have two older Briggs push mower engines that would barely pop that far. One was less than that line a touch. 3/16" or less like hardly anything. And if you run a resistor plug, you have less spark than that. Oh my test was without the plug and grounded to the block, bare metal. Now running ALL non resistor plugs in everything.

 

[slomo]

Update

Ordered new coils. Bought a Stens "made in Germany" coil. It fires basically double the old 1989 year era Briggs spark gap. It pops between the S and E on that dividing line. Still not impressed.

Second newer Briggs got a cheapo Chinese 12 dollar coil. It pops the same distance as the Sten's German one. Now if it will last more than 2 mows LOL.

Checked a friends old 1998 Toyota Corolla with the 1.8 liter 4 cylinder. That Godzilla monster popped at the line just left of the number 4. That spark tester is nearly the width of your palm. It fired a massive spark like you do not go near it cause she is hungry. THAT was impressive. Look how far that is.

 

[Auto Doc's]

Hi Slomo,

A small factor that I learned about (the hard way) just a few months ago was to make sure the metal frame mount area of the coil is free of rust and the aluminum stands are clean aluminum in the mount area. Along with that, the hold down bolts cannot be gold anodized.

It took me some switching a swapping of parts to finally arrive that the anodized bolts were the biggest problem.

All of these seemingly little factors greatly impact how well a coil can produce a good "blue" spark.

Another problem with spark testers that has presented itself more recently is cheap open-gap spark tester with poor/ very loose adjuster thread fitment. I have compared a couple of these cheap ones against my original old school B&S small engine spark tester. The cheap new ones were questionable when it came to showing a consistent spark.

Here is an eBay example similar to the PET 4000 but it cost quite a bit less.