# 1968 GTO - No Sparking Present



## The Patchwork Tiger (Apr 8, 2009)

Hello fellow Enthusiasts!

I know there are a multitude of non sparking issues in the forum, however, this instance has me at a loss of a solution . . . for the moment.

Car has been parked since last November until now.
I have a dilemma in trying to determine why no spark is being made from the coil. This was begun by pulling the coil wire and resting it next to the opening of the coil, pressing my remote push button bypass switch to check for arcing and nothing. Car is stock, no aftermarket items. I have attempted the following without resolve:

- Different coil wire

- Two different coils

- Used a probe from the + of the battery to both + & - of coil, both light
- Used a probe from the - of the battery to both + & - of coil, both light 

- Changed points and condenser

- Alternator is good

- Made a closed loop with the probe to check continuity in red and "blk sngl ylo" wires going to the + of the coil in the engine harness, good

- Different ignition switch

- Checked continuity in fuse block with key off and in run position, good

- Checked continuity at the ignition switch, good



What else to check?

Thanks for the responses

Alex


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## gjones (Oct 8, 2012)

*B+ plate voltage, 0vdc, cathode installed, cold heater*

Maybe I'm reading this wrong, but did you say you pulled the wire out of the _coil_, then rested it next to the coil hole? If that is correct, then that's wrong. Pull the wire off the distributor, then secure it about 1/2" away from a clean bolt on the intake, heads, or anywhere else that is a good ground (as far away from the fuel line and/or carburetor as possible), _then_ crank it. Should be a nice blue spark. Plug your wire back in. Turn the key to the "on" position. Should have power on the positive side of the coil. (If not, there is a problem with the primary side the circuit). Then crank it while using your test light on the negative side of the coil. Should flicker. That'll tell you if at least your points are working (not that they're adjusted properly, though). DO NOT crank it with the coil wire off, or not close to ground as mentioned above! If you're totally stock, you should also have a ballast resistor, which can also go bad. These are only a few dollars-cheap insurance-if in doubt, change it out. Those old neutral safety switches are a source of consternation, also. Perhaps you *ARE* getting spark, but just no fuel to the carb??? Did you try drizzling a *little* gas down the carb, then try to fire it up? Worth a shot. Good luck t' ya!  P.S. Negative side of the coil goes to the distributor!


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## geeteeohguy (Feb 2, 2008)

It sounds like your ignition points have a worn out rubbing block. Pull the dist. cap and crank it over, and check if the points are opening and closing. I'll bet they're not. Install a new set of points and a new condensor, set the dwell with a dwellmeter (or gap them at about .016-.018) and go from there. Be advised that these cars do not have a ballast resistor, just a resistor wire. You need about 9 volts getting to the + side of the coil.


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## gjones (Oct 8, 2012)

*ballast weight*

Sorry, gt. You are correct about the resistor wire. However mine has a ballast resistor also, (installed by PO), when they installed the new Mallory Unilite distributor and coil. Apparently, those Mallory units don't even like to see more than a few volts, or this is an incorrect set up. If this is incorrect, would the engine run as good as it does? Now you've got me wondering. This also has the resistor wire, in addition to the ballast. Egads! :willy:


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## geeteeohguy (Feb 2, 2008)

Gjones, you could throw it on a scope and check the KV of the coil on the 'parade' pattern....you want something over 30 KV when you snap the throttle. If it runs good and doesn't burn up points, I would not worry about it. 31 years ago, when I bought my '65 GTO, it had a 428 in it that didn't run as good as it should....ran slower than my '66 with a 389. I threw it on the scope at work, and the ignition coil was hooked up backwards!!!


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## The Patchwork Tiger (Apr 8, 2009)

Sorry, wire set next to the distributor, cranked and no spark jumping from cap to wire.


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## Rukee (Feb 8, 2007)

Don't put the wire next to the cap, put it 1/2" away from a solid ground, like the intake manifold, base of carb, valve cover etc.


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## gjones (Oct 8, 2012)

*Hell hath frozen.*

Um, did you read my first response? It'll be a cold day in hell before the spark will jump from the "center of the cap to your wire". Especially if your terminals are recessed in the cap. Voltage goes from coil to cap. Not the other way around. (Lest ye be pushin' 80-100,000 volts, then maybe it'll jump the gap from the coil wire to the distributor terminal, but unlikely. This ain't no lawnmower!).-*And this ain't the Dewars talkin', neither!*


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## Rukee (Feb 8, 2007)

Right, the spark is going to jump from the coil wire (disconnected from cap) to ground.


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## gjones (Oct 8, 2012)

*coiled and ready*

P.S. If your coil wire (the side that plugs into the distributor) is particularly deeply recessed, sometimes you have to shove a screwdriver (or metal rod the correct size for the terminal end) into it, then place the screwdriver (or rod) shank near ground (1/2" away). If your using the remote cranker, make sure your ignition key is "on". (You never know how someone rigged that!).


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## OhioLS2 (Jun 10, 2013)

its your distributor...

has to be


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## The Patchwork Tiger (Apr 8, 2009)

Key in run position, coil plug wire close to manifold for ground, cranking and . . . . . no spark.


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## gjones (Oct 8, 2012)

With the key in run position, what voltage are you looking at, at the coil + side?


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## The Patchwork Tiger (Apr 8, 2009)

With key in "RUN" position, using multimeter and touching the (plus side) of coil . . . . reading 12.31 volts.

Pulled cap and did the same with the points, getting spark when touched with (plus lead), but no reading at the meter.


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## gjones (Oct 8, 2012)

*rubberblock*

Back to geeteeohguys' rubbing block theory. You said you put a new set points in it, then make sure there even IS a rubbing block on the points -a little plastic deal that rides on the cam lobes on the distributor shaft. (Seen them completely gone before). They used to give you a little capsule of rubbing block grease with new points. Use it if you have it. Are these the kind of points that have the built in condenser, or does the condenser have a separate wire? You do have a new condenser, yes? (A bad condenser can cause no spark, also). Did you set the points with a feeler gauge, with the points' rubbing block on the highest point on the cam lobe, (again, as per geetee's advice)? If the adjusting screw at the points are too tight, they may never close properly. Sounds like there is no resistor wire going to the coil on your system, either. (If not, it'll be seeing 14+ volts there when the engine is running-too much). Had a no spark issue on my '56 New Yorker once. Turned out to be rotten wires inside the distributor. Changed them out, & problem solved. If the insulation on the wire in the distributor is chaffed anywhere, it could be grounding out, causing this condition.


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## BearGFR (Aug 25, 2008)

The Patchwork Tiger said:


> With key in "RUN" position, using multimeter and touching the (plus side) of coil . . . . reading 12.31 volts.
> 
> Pulled cap and did the same with the points, getting spark when touched with (plus lead), but no reading at the meter.


Normal to get no voltage reading at the points _if they're closed when you take the reading_ because with them closed that part of the circuit is grounded.

Try this:
Remove cap, bump the starter until the points are OPEN. Turn ignition to RUN, measure voltage from the wire on the points to ground. You should have voltage. If you don't and you still have voltage at the coil + terminal, then the problem is either in the wire from the coil - (minus) terminal to the points or the primary winding in the coil is open (coil is bad), or the condenser is shorted (disconnect the condenser wire and test again to check for that).

If you DO have voltage at the points (between wire terminal and ground, with them open), then do this:
bump starter until points are closed
ignition to RUN
pull coil wire from distributor (leave connected to coil) and position the free end close to a good ground.
Take a wooden stick or something and push the points open.
You should get a spark at the end of the coil wire when they open. If you don't, then the problem is in the coil secondary winding (coil is bad) or a bad coil wire.

Bear


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## The Patchwork Tiger (Apr 8, 2009)

*Sparking issue resolved!*

Discovered it was the grounding lead on the breaker plate. Loosened and re tightened the retainer screw to disturb scale. Reassemble and remote cranked with coil wire near manifold, and . . . . spark! 


Thanks to all for input on the matter!

Will also have some photos posted soon.


Alex


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## gjones (Oct 8, 2012)

*The black arts of sparkulation*

Hot diggetty damn! Thaz the ticket! Good deal! :cheers


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## chuckha62 (Apr 5, 2010)

The Patchwork Tiger said:


> Discovered it was the grounding lead on the breaker plate. Loosened and re tightened the retainer screw to disturb scale. Reassemble and remote cranked with coil wire near manifold, and . . . . spark!
> 
> 
> Thanks to all for input on the matter!
> ...


Dammit!

I was reading your thread and was thinking, "it's the Breaker plate ground..."

Congrats on finding it.. That problem has stumped many before you!


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## The Patchwork Tiger (Apr 8, 2009)

*Yeah, and photos . . . .*

Yeah, it is always the most simplistic items that get overlooked until the end . . 


And photos are posted


Thanks, Alex


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