What is the easiest way to test to see if I have spark going to the plugs without firing the motor over?
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Testing for spark-Updated -Spark issue fixed !!
- Thread starter cmayna
- Start date
AzPete
Well-Known Member
Re: Testing for spark
Wire the plugs and lay them on the block. Be sure the plug is grounded. Crank the engine and watch for spark. Do this for all eight and you know what you have.
Wire the plugs and lay them on the block. Be sure the plug is grounded. Crank the engine and watch for spark. Do this for all eight and you know what you have.
A
Anonymous
Guest
Re: Testing for spark
and if you don't want to crank the engine over, remove the distributor and spin it by hand....works the same.
and if you don't want to crank the engine over, remove the distributor and spin it by hand....works the same.
Re: Testing for spark
During the daytime, it may be difficult to see the spark so what's helpful is if you place your tongue at the tip of the plug to check for spark as someone is cranking the engine. Good luck with the (eventual) firing.
"AzPete" said:
During the daytime, it may be difficult to see the spark so what's helpful is if you place your tongue at the tip of the plug to check for spark as someone is cranking the engine. Good luck with the (eventual) firing.
A
Anonymous
Guest
Re: Testing for spark
:WOP
:WOP
Re: Testing for spark
I was lazy tonight and pulled all the wires but just one plug. When I cranked it over, the only time I saw a spark was when I let up on the trigger. Is this normal?
I was lazy tonight and pulled all the wires but just one plug. When I cranked it over, the only time I saw a spark was when I let up on the trigger. Is this normal?
stump
Member
Re: Testing for spark
So much for my note taking...
"SAC69" said:
So much for my note taking...
AzPete
Well-Known Member
Re: Testing for spark
You should see spark every time the rotor comes around to that plug wire.......
You should see spark every time the rotor comes around to that plug wire.......
Re: Testing for spark
Usually I just take one wire off and connect it to a spare plug.
Do you have 2 wires going to the coil's + terminal... One should be for "run" mode, the other should be for "cranking" I beleive. When we tried to fire up my buddies 67 428 without all the dash / guage wiring complete he had the same issue and we ended up manually running a bypass wire from the battery to the coil to get it fired up. I think when we installed the gauges, we found a single terminal wire under the dash that took care of it. I think it was the pink wire on the stock harness. On the painless harness look over wires 920 and 970.
"cmayna" said:
Usually I just take one wire off and connect it to a spare plug.
Do you have 2 wires going to the coil's + terminal... One should be for "run" mode, the other should be for "cranking" I beleive. When we tried to fire up my buddies 67 428 without all the dash / guage wiring complete he had the same issue and we ended up manually running a bypass wire from the battery to the coil to get it fired up. I think when we installed the gauges, we found a single terminal wire under the dash that took care of it. I think it was the pink wire on the stock harness. On the painless harness look over wires 920 and 970.
Re: Testing for spark
I am running painless, so I will look into this. I am also running MSD.
I am running painless, so I will look into this. I am also running MSD.
Mach1Rider
Active Member
Re: Testing for spark
Trace the brown wire ( I term on Sol) to make sure your getting power to the coil when cranking.
Your remark of only seeing spark when letting off has me leaning towards an open in your wiring.
Trace the brown wire ( I term on Sol) to make sure your getting power to the coil when cranking.
Your remark of only seeing spark when letting off has me leaning towards an open in your wiring.
oateater
Member
Re: Testing for spark-Updated with a possible issue
FYI: I know this is a completely different system, but my rv did the exact same thing last summer and I ended up changing the electronic control unit. When I let go of the key from start mode I lost ignition. Took me a while to fiqure that one out. Then it was a guesing game between the control unit and the coil. I guest right.
"stump" said:
FYI: I know this is a completely different system, but my rv did the exact same thing last summer and I ended up changing the electronic control unit. When I let go of the key from start mode I lost ignition. Took me a while to fiqure that one out. Then it was a guesing game between the control unit and the coil. I guest right.
Re: Testing for spark-Updated with a possible issue
Stangg and Mach1,
Guess what? My Ferrari mechanic neighbor came over to see how I'm doing on the car. I mention the lack of spark issue and he started helping me do some trouble shooting. Tested this, tested that.
He pulled the coil wire from the dizzy and installed the pulled spark plug, laid it again the valve cover saying that when cranking it should be zapping a lot. We tried and nada. Humpph.
He looked at the + post of the coil and asked what the brown wire was for. I said it is coming from from the I post of the solenoid. He looks at me, smiles and says "I need to go do a quick errand, you need to disconnect that brown wire (painless #970) from the coil and join it with the ignition wire coming from the ignition key and goes and feeds the MSD box. I'll be back"
Damn it, he was dead on !!!! I hate him for now I'm really running out of excuses to not fire the puppy up.
As soon as he started question the brown wire, I remember you guy's replies about this possibility.
Thank you.
Craig
Stangg and Mach1,
Guess what? My Ferrari mechanic neighbor came over to see how I'm doing on the car. I mention the lack of spark issue and he started helping me do some trouble shooting. Tested this, tested that.
He pulled the coil wire from the dizzy and installed the pulled spark plug, laid it again the valve cover saying that when cranking it should be zapping a lot. We tried and nada. Humpph.
He looked at the + post of the coil and asked what the brown wire was for. I said it is coming from from the I post of the solenoid. He looks at me, smiles and says "I need to go do a quick errand, you need to disconnect that brown wire (painless #970) from the coil and join it with the ignition wire coming from the ignition key and goes and feeds the MSD box. I'll be back"
Damn it, he was dead on !!!! I hate him for now I'm really running out of excuses to not fire the puppy up.
As soon as he started question the brown wire, I remember you guy's replies about this possibility.
Thank you.
Craig
70_Fastback
Hell Bent for Speed
Re: Testing for spark-Updated with a possible issue
I would have kicked him in the nuts if he did that to my VC. Would have left a nice burned arc mark on it.
"cmayna" said:
I would have kicked him in the nuts if he did that to my VC. Would have left a nice burned arc mark on it.
crustycurmudgeon
Well-Known Member
Re: Testing for spark-Updated with a possible issue
It'll buff out.
Frank
"70_Fastback" said:
It'll buff out.
Frank
66gt350
Active Member
I fired up my fastback this past weekend after messing with it. I forgot to hook up #3 spark plug. I could hear it sparking off the back of the alternator from inside the car. I'd hate to see what that would have done if it had been resting on the valve cover...
OH you guys are a bunch of Va Jay Jay's. It left no burnt marks.
70_Fastback
Hell Bent for Speed
Because you had no spark at that moment. Ya schmuck.