How to build a bench top Spark Plug tester

Thread Starter

Gdrumm

Joined Aug 29, 2008
684
I've got a bunch of old lawnmower spark plugs I would like to test.

I saw bits of a Youtube video in Russian, that shows one, with a coil and some other components I couldn't reccognize.

Any thoughts on how I could make one?

I have boxes full of electronic components I've saved.

Surely there is an easy way to make one.

Any ideas?

Searches on Google just produces a million or so ads for spark plugs.

Thanks,
Gary
 

MaxHeadRoom

Joined Jul 18, 2013
21,436
Pick up an old style ignition coil and a distributor from a wrecker get an old single cyclinder cycl head from a mower etc to screw the plug into, and you have all the makings for probably less than $10.00.
Not elegant electronics, but would work.
Or a 555 and a Mosfet in the primary of the coil, if you want the elegant way?
Max.
 

Thread Starter

Gdrumm

Joined Aug 29, 2008
684
Thanks Max,
Gets me thinking.

I have an old chainsaw that doesn't work, but has spark.
It has no bar or chain either.

I can remove the recoil and use a socket and drill to rig it for easy turnover, then connect the wire, and lay the sparkplug against the head, and give it a go.

That should work.

Gary
 

MaxHeadRoom

Joined Jul 18, 2013
21,436
There you go! ;)
Also you could get a piece of Aluminum plate and get it drilled and tapped with the 2 most popular sizes, 14mm 18mm ??
And bolt the plate to the head or a bolt on the casting.
Max.
 

Thread Starter

Gdrumm

Joined Aug 29, 2008
684
The old chain saw idea worked great.
I went through a dozen old spark plugs, and found that 1/2 of them were good.

It wasn't rocket science ..... oops; ...surgery.
But it was Chain Saw Surgery, and that sounds scary here at Halloween.

Thanks,
Gary
 

shteii01

Joined Feb 19, 2010
4,644
The old chain saw idea worked great.
I went through a dozen old spark plugs, and found that 1/2 of them were good.

It wasn't rocket science ..... oops; ...surgery.
But it was Chain Saw Surgery, and that sounds scary here at Halloween.

Thanks,
Gary
Just for the record... How many rolls of duct tape were used?
☺
 

shortbus

Joined Sep 30, 2009
7,946
The only thing with all of this is, when a plug is under cylinder compression it may not fire, when it will at atmospheric pressure. Why were the plugs removed from the motors? Probably cause they didn't work.:)
 
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