Spark Gap Tool - what is this for?

[oltruckag]

Ok, finally moving into my new garage (I should update my over budget past schedule build thread) and I’m cleaning and organizing my tools.

I’ve got a collection of 3(+?) generations of tools, parts and junk to go through and for the most part I know what everything does / is used for but this one stumps me. I think it’s for testing an ignition coil, but wanted GJ input to see if anyone really knows for sure.

What say the hive?

Tyson

 

[Technologyteacher]

Spark tester

 

[nadogail]

The larger distance the spark will jump means that it is a better coil.

 

[oltruckag]

Ok, I think agree with both that it’s a spark tester, let’s get a bit more detailed now that we know what it is. How does one use it?

I guess I clip it on to metal for ground and attach the plug lead to one of the adjustable screws. Why are there two screws? Is there a testing procedure to determine the best coil for ? Is this a track tool for the drag strip or just a common tool for testing and changing coils? Usually a bad coil is a bad coil, I’m not even sure I could diagnose a weak one with drivability issues.

Honestly would like to know, dad probably knew but unfortunately I’m years past being able to ask him….

Tyson

 

[Fedwrench]

That looks like an old Briggs & Stratton spark tester, hasn't been made in decades. There's one on ebay.

 

[qqzj]

Ok, I think agree with both that it’s a spark tester, let’s get a bit more detailed now that we know what it is. How does one use it?

I guess I clip it on to metal for ground and attach the plug lead to one of the adjustable screws. Why are there two screws? Is there a testing procedure to determine the best coil for ? Is this a track tool for the drag strip or just a common tool for testing and changing coils? Usually a bad coil is a bad coil, I’m not even sure I could diagnose a weak one with drivability issues.

Honestly would like to know, dad probably knew but unfortunately I’m years past being able to ask him….

Tyson

Two screws to provide more angles and easier to use? The extra adjustable screw is useless anyways. My guess.

 

[vssjim]

I ould say to test a twin lead coil

 

[MileHighRover]

Briggs & Stratton still makes that today, just looks a little different. Here's the instructions.

Testing Ignition

Here's the tester - spark tester

 

[Pinemarten]

The shorter screw is the ground side. They are adjustable to increase the "gap" to simulate the gap of your spark plug.
Far easier to get good connections with this tool, than setting a plug on a grounded surface and pulling engine over.

 

[Steve_P]

Yes, that's by Briggs and Stratton, or a clone; we had these in the small engine shops that I worked at in the 1980s. One time I was testing spark on a push mower, the same way I'd done it hundreds of times before- spark plug out, tester installed. Well, the tester was in front of the open spark plug hole, and when I pulled the rope, I started a small fire LOL- there was obviously a small amount of fuel in the chamber. I put it out in a second or two, somehow, maybe a rag, not a fire extinguisher, and always kept the tester away from the spark plug hole after that.

edit- I do like how in the last pic the beer can says "create a spark" on the top.

You install one of the two screws into the clip in the plug wire, then clip it to ground. Make sure not to have it in front of the open spark plug hole!

 

[Wakefield]

Yes, that's by Briggs and Stratton, or a clone; we had these in the small engine shops that I worked at in the 1980s. One time I was testing spark on a push mower, the same way I'd done it hundreds of times before- spark plug out, tester installed. Well, the tester was in front of the open spark plug hole, and when I pulled the rope, I started a small fire LOL- there was obviously a small amount of fuel in the chamber. I put it out in a second or two, somehow, maybe a rag, not a fire extinguisher, and always kept the tester away from the spark plug hole after that.

edit- I do like how in the last pic the beer can says "create a spark" on the top.

You install one of the two screws into the clip in the plug wire, then clip it to ground. Make sure not to have it in front of the open spark plug hole!

I think Echo makes/sells a nice one,the spark gap inside the window might be adjustable (chainsaws might use a different gap than a lawnmower)