Spark tester.
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What’s a good brand spark tester to buy? I’ve got the Lisle style that the plug wire boot slips on one end with the alligator clamp on the other but that doesn`t always give me enough length to clip to a good ground. Looking for a pig-tail style or something similair. Thanx,Mike.
Use your Lisle, then just run an alligator clip wire from it to a good ground.
I thought of that at breakfast. DUH. Thanx.
I ordered a set of these Accu Spark inline testers from Britain and as soon as they arrive, I’ll post a report on them.
Here they are in action being used by fellow outboarder kodibass on a ten horse Johnson. If you don’t want to watch the whole video, he has good shots of them at 1:04 and 12;41 in this video.
Another trick is to just use an old cylinder head with the good plugs screwed into it. It can either be bolted to the block or grounded by using a short piece of wire with an alligator clip on the end. This way you can see all two, four, or six ignition systems firing at once.
If you want to go “old school”, get a new spark plug, hose clamp, and a wire lead with an alligator clamp. Hose clamp the wire to the threads of the plug. Attach plug wire to plug, clip lead to a good ground on the motor, crank away. Worked for Grandpa, Dad, me, and my son. Yes, I have a Harbor Freight tester, but I can’t always see it in the light. I can hear a good spark “snap” with the homemade tester.
If you have too many, AND not enough, you're a collector.
If you want to go “old school”, get a new spark plug, hose clamp, and a wire lead with an alligator clamp. Hose clamp the wire to the threads of the plug. Attach plug wire to plug, clip lead to a good ground on the motor, crank away. Worked for Grandpa, Dad, me, and my son. Yes, I have a Harbor Freight tester, but I can’t always see it in the light. I can hear a good spark “snap” with the homemade tester.
Kerry, just one thing to add to this to potential new people reading that may not know. Ill assume you open your plug gap up to 1/4″ not 020, but new members reading this may not know that.
For new members, it is a lot harder for a plug to fire under compression in the cylinder then it is out of the plug hole in open air. That is why it must jump a 1/4″ gap in open air, to say that the ignition is sufficient. Simply jumping an 020 gap in open air, does not necessarily mean it will fire under compression, and does not necessarily mean your ignition is functioning as it should. You may be chasing your tail for days trying to figure out what is wrong!
I have had more than a handful of guys bring their motor to me to look at. They said they had good spark since the plug would spark when holding it up to the block. When I put my inline tester on it at 1/4″ gap, no fire. Weak ignition.
I fell for that myself in the past since I read it on the old internet! Someone on here set me straight, and Ill never forget it now.
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>>Another trick is to just use an old cylinder head with the good plugs screwed into it. It can either be bolted to the block or grounded by using a short piece of wire with an alligator clip on the end. This way you can see all two, four, or six ignition systems firing at once.>>
Sheesh Mumbles….why didn’t I think of that! Especially when I’m testing spark on an older motor that has spark plug terminals of the old type that don’t fit onto the tip of a Lisle-type tester…..
As for the Accu-Spark type testers (and other Neon Testers) one thing I have found is that they seem to light up with even the weakest of spark…..so they are OK for showing the existence of spark bu they are not very useful for ascertaining that the spark is strong enough to fire under compression.
I agree about neon testers lighting up easily but I did see a video somewhere demonstrating weak spark using the Accu Spark testers. The culprit cylinder definitely had a dimmer flash than the other good cylinders had. Maybe being red instead of white light makes it more noticable. I sure wish I had bookmarked that video as I can’t find it now.
Removing the ground electrode altogether on the home made tester should work just as good as opening the gap. Yeah, I know the gaps aren’t opened up in this old photo but it was taken right after the build.
Another involuntary way I’ve found good spark is by accidently getting my paws too close to the spark plug of a running motor. With rubber spark plug boots or not, touching in this area will let you know what is good and what isn’t. This hands on method isn’t recommended for anyone with a pacemaker!
Just a heads up but beware of these proximity pencil style spark testers sold on Epay and other places. I gambled my money and lost. It never did work and I never did get refunded for it. Live and learn.
I cut the side electrode off. then you have an excellent gap to jump with a good ignition .
Make one with short piece 1 x 2 drill 1/2 hole near one end. The drill hole from side into 1/2 hole. Screw 1/4 x 20 bolt into hole and cut off head. Drill hole opposite side from bolt and screw wood screw here. Hook plug wire to bolt and connect jumper wire with clips on each end, one to screw the other to ground. Now keep turning screw out until spark stops. If you have real good spark you will have about 1/4 gap. And don’t turn screw when spark jumping. Cost two small clips.
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