74 914 2.0
How do I check that I am getting spark? I have an Crane Fireball electronic ignition..... Fuel Pump is working, car turns over but will not start?? All the wires are correct..
Full Version: How to check for ignition spark?
easiest way is to pull a plug wire, stick an old plug in it, ground the threads of the spark plug (hold it against the engine tin is fine) and have someone crank it. You should see the plug fire, and ideally it will be a big fat blue spark
I always use my inductive timing light.
Tom
Tom
QUOTE(Crazyhippy @ Jul 5 2010, 11:24 AM) 
easiest way is to pull a plug wire, stick an old plug in it, ground the threads of the spark plug (hold it against the engine tin is fine) and have someone crank it. You should see the plug fire, and ideally it will be a big fat blue spark
- Yeah, but LAY it on a grounding metal part of the motor (hex/nut part will ground it too IIRC) - cuz you don't want to be an alt. ground for 10,000 volts Joe! 
Bad news to stand there holding it - dudes & dudettes!
PS - Just use the new plug(s) that you want to check, in order to make sure that the actual plug you're using is good & getting spark. If you use the old plug, then you won't know if you have a good or bum plug! .... it can happen NIB on occasion.
QUOTE(Tom @ Jul 5 2010, 11:50 AM)
I always use my inductive timing light.
Tom
On a few occasions where you have a shorted plug inside, this method can give you a false positive. .... besides, laying the plug on the engine is cheaper!
... wired up of course after you pull it - & check that all plug to wires to dizzy & coil connections are solid first!
I usually try the coil wire first as it is easier to pull out of the cap and watch then try the plug if the coil has spark. Sometimes plug wires can get messed up when you pull them and I don't like causing any other problems than I already have.
QUOTE(Tom_T @ Jul 5 2010, 12:11 PM)
QUOTE(Crazyhippy @ Jul 5 2010, 11:24 AM)
easiest way is to pull a plug wire, stick an old plug in it, ground the threads of the spark plug (hold it against the engine tin is fine) and have someone crank it. You should see the plug fire, and ideally it will be a big fat blue spark
- Yeah, but LAY it on a grounding metal part of the motor (hex/nut part will ground it too IIRC) - cuz you don't want to be an alt. ground for 10,000 volts Joe! Bad news to stand there holding it - dudes & dudettes!
PS - Just use the new plug(s) that you want to check, in order to make sure that the actual plug you're using is good & getting spark. If you use the old plug, then you won't know if you have a good or bum plug! .... it can happen NIB on occasion.
I would add: Ground the plug with a jumper cable. It's jaws are large enough to hold a plug. Best of both worlds. You ain't touching it and you have a good ground. I learned the hard way! 
.....Y..ye...Yes....Y...Yo...YOU....D..Do...don...don't.t t.t....w...wa...wan...wanttttt.....t...to...tooo...H...Ho...HOL...HOLD....the ...s..ss..p..spa...spar....spark....Ppp...pl..plu...plug.........a.....aaa....as.....y...yo...you....c...ca.....cannnn.....can....bB.BBBB.BBB....be .....t...th....tha.....the.....G...rrrr...gr...grrrrr...gro...grouuuu....grounddd.ddd...GROUND.
got spark.. done
QUOTE(Tom @ Jul 5 2010, 10:50 AM)
I always use my inductive timing light.
Tom
I agree. Doesnt get much easier than that.
Harbor Freight sells a cheap ignition tester for a about $5. It clips on tho the end of the plug and you'll see the spark as it's cranking.
QUOTE(Tom_T @ Jul 5 2010, 12:11 PM)
QUOTE(Crazyhippy @ Jul 5 2010, 11:24 AM)
easiest way is to pull a plug wire, stick an old plug in it, ground the threads of the spark plug (hold it against the engine tin is fine) and have someone crank it. You should see the plug fire, and ideally it will be a big fat blue spark
- Yeah, but LAY it on a grounding metal part of the motor (hex/nut part will ground it too IIRC) - cuz you don't want to be an alt. ground for 10,000 volts Joe! Bad news to stand there holding it - dudes & dudettes!
PS - Just use the new plug(s) that you want to check, in order to make sure that the actual plug you're using is good & getting spark. If you use the old plug, then you won't know if you have a good or bum plug! .... it can happen NIB on occasion.
The best is working on an IMCA modified w/ a BIG coil, and MSD... You are leaned over the motor, and your beltbuckle (or anatomy associated w/ that area) is leaned up against the car
Will not make that mistake again 
Holding the plug wire is fine though
lol, when I was about 13 I was trying to fix a lawn mower... checked the spark as described but le my finger get a little too close... OUCH! and that was just a 1hp Tecumseh...
Yeah, plug wire will just make ya let go. Grab the coil wire. That will put you to your knees.
To pull a plug to check for spark is asking for a galled/ stripped plug unnecessarily. Told to me by an old motorcycle mechanic back in the 70's.
Much easier to see if the ignition system is working by the least invasive means and then going from there.
Tom
Much easier to see if the ignition system is working by the least invasive means and then going from there.
Tom
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.