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Discussion Starter #1
Just swapped out the Holley 600 cfm for a Summit 500 cfm carb and replaced the dash gauges with Classic Instruments. Now car won't start. Cranks over, gas to carb. Float bowls filled up very quickly.

Part of the instrument replacement was a volt meter. I disconnected the ammeter and taped off the ends. Do they need to be connected for the ignition to work? Looking at the wiring diagram, it looks like they shouldn't.

How can I check to see if I have power to the system when cranking? Is this a two person job? I have the original distributor but with a pertronix inside. Car worked before the carb and instrument swap.
 

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Discussion Starter #2
More info, no spark. Pulled #1 plug and grounded it while cranking-no spark. With key on, put volt meter on + of coil and - of battery, no volts. Did the same while cranking and got 10V of current.

How do I test my coil? It s fairly new pertronix flame thrower.

Should I consider putting my points back in?
 

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Discussion Starter #3
Update to my update.

I'm an idiot. I had the engine feed wire going to the neg side of the coil. I switched it and now I only have 8 volts across the coil.

New question: I ruined the coil right?
 

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Not likely. The coil has reduced voltage during cranking.
 

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Although the coil is marked + & - or BAT & DIST it will work either way, just at reduced performance when connected backwards.
If you have power at the coil but no spark did you put the rotor back in place?
 

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Discussion Starter #6
Although the coil is marked + & - or BAT & DIST it will work either way, just at reduced performance when connected backwards.
If you have power at the coil but no spark did you put the rotor back in place?
Yes, rotor is back and the contacts look good. I had no spark when I had the coil hooked up wrong (+ from dizzy to + coil and - from dizzy AND engine harness to -coil). I switched it to +from dizzy and engine harness to +coil and - dizzy to -coil. Didn't check to see if plug has spark. I assumed it would. I'll check tomorrow.

Just checked coil and still has 1.5 ohms. Any way to test the coil?

What about the dash wiring? Can you start a car without the dash installed? I have a rally pack and that is hooked up. I think if it wasn't the car wouldn't even turn over, correct?
 

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The tach in the Rally Pac installs in series with the Pink wire so if it is disconnected the engine won't run with the key in the Run position. It will start with key in the Start position because the coil is receiving full 12V from the I post on the solenoid in Start but it will die as soon as you release the key to Run.
Check the big wire coming out of the coil going to the center of the distributor for spark. Either connect an inductive timing light to that wire or pull it out of the distributor and hold it close to a ground while cranking the engine with a remote starter switch or by jumping the solenoid. Be sure the key is in Run position when you do this and verify the transmission is in Park or Neutral.
 

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Discussion Starter #8
The tach in the Rally Pac installs in series with the Pink wire so if it is disconnected the engine won't run with the key in the Run position. It will start with key in the Start position because the coil is receiving full 12V from the I post on the solenoid in Start but it will die as soon as you release the key to Run.
Check the big wire coming out of the coil going to the center of the distributor for spark. Either connect an inductive timing light to that wire or pull it out of the distributor and hold it close to a ground while cranking the engine with a remote starter switch or by jumping the solenoid. Be sure the key is in Run position when you do this and verify the transmission is in Park or Neutral.
I double checked the rally pac wiring, its correct.

I have and inductive timing light, so just hook it up to the coil wire (instead of plug #1) and press the trigger while cranking?

How do you "jump the solenoid"? Send 12 V to the post going to the starter? Incidentally, I pulled the coil off and the primary windings show 1.5 ohms but I get 0 ohms from the secondary windings.
 

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Testing the coil secondary... ohmmeter to 20k ohms scale... one lead on coil+, the other in the high tension tower. You should have 7.5k to 14.5k ohm +/-....

If you want to "test" the coil, pull the wire from the center of the distributor cap and stick an old spark plug in it and place on a decent ground. Disconnect the coil- (black) wire. Turn the key on. Grab a suitable jumper wire and place one end on the coil- and ground the other end. Each time you remove the wire from ground you should get a spark.
 

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Discussion Starter #10
Testing the coil secondary... ohmmeter to 20k ohms scale... one lead on coil+, the other in the high tension tower. You should have 7.5k to 14.5k ohm +/-....

If you want to "test" the coil, pull the wire from the center of the distributor cap and stick an old spark plug in it and place on a decent ground. Disconnect the coil- (black) wire. Turn the key on. Grab a suitable jumper wire and place one end on the coil- and ground the other end. Each time you remove the wire from ground you should get a spark.
I'm getting 9.34, so thats good. I think my coil is fine.

Could it be I flooded the engine since I was cranking it for a bit with the coil wired wrong?

I'll put the coil back in tomorrow and see if I get a spark to the distributor central wire.
 

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I have and inductive timing light, so just hook it up to the coil wire (instead of plug #1) and press the trigger while cranking?
Yes.

How do you "jump the solenoid"?
Use a screwdriver to bridge the gap between the large Battery post to the small S post on the solenoid.
 

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Discussion Starter #13 (Edited)
Testing the coil secondary... ohmmeter to 20k ohms scale... one lead on coil+, the other in the high tension tower. You should have 7.5k to 14.5k ohm +/-....

If you want to "test" the coil, pull the wire from the center of the distributor cap and stick an old spark plug in it and place on a decent ground. Disconnect the coil- (black) wire. Turn the key on. Grab a suitable jumper wire and place one end on the coil- and ground the other end. Each time you remove the wire from ground you should get a spark.
Coil is ok. I got a spark everytime i lifted the ground from the coil

Pull a plug(s) to see if they're wet.
Plugs are not wet

@awhtx

So I pulled the center wire from the dizzy and put it pretty close to the engine. With the engine on, I jumped the starter and got no spark (maybe I wasn't close enough), than I put my timing light on (Actron cp7528) and didn't see any strobe. Went to O'Reilly's and got a new accell 8140C 1.4 ohm coil and that didn't make a difference. ( Pertronix tech support said this one was compatible)

The Pertronix guy said I may have damaged the module. he's sending me instructions on how to test that.

At this point is it worth putting the points back in? How easy is that to install and set. I took them out and saved all the parts.

If the Ignitor module isn't damaged, could there possible be a way to screw up the dash wiring that would cause this?

I know with the ignition on, i'm getting 9V to the coil.

Thinking it time to move on and re-screen some windows!
 

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Discussion Starter #14
I did some reading on how the ignition system works. Am I correct: When you turn the key to start, power goes to the S post on the solenoid and out thru the I post and the brown wire which hooks up to the red/green wire and delivers power to the + side of the coil while cranking. With the key in the run position, power to the coil is supplied by the red/green wire.

Would a problem in this circuit explain why I have 9 volts to the +coil when in run and no spark when in start? With the key on run, I have 9 volts to the I post. If I have someone turn the car over and measure volts from the I post to ground would that help?

Even if the Pertronix modulator is fried, I should still have a boat load of spark exiting the coil, correct?

Maybe my ignition switch failed? I got a new one from NPD but they sent me the wrong one and I reinstalled my old on. I'll look at that.

Anyone have anything else I should look at?
 

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Even if the Pertronix modulator is fried, I should still have a boat load of spark exiting the coil, correct?
No. The coil works like this. When the points are closed the coil builds up a charge. When the points open the coil dumps this built up charge into the coil wire to the distributor. Replace the points with a Pertronix or other electronic trigger and instead of mechanical points opening and closing you have magic inside the little black box that opens and closes the circuit. If the module has failed then there is no opening and closing of the circuit and the coil doesn't build up a charge.
 

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Discussion Starter #16
No. The coil works like this. When the points are closed the coil builds up a charge. When the points open the coil dumps this built up charge into the coil wire to the distributor. Replace the points with a Pertronix or other electronic trigger and instead of mechanical points opening and closing you have magic inside the little black box that opens and closes the circuit. If the module has failed then there is no opening and closing of the circuit and the coil doesn't build up a charge.
Got it. I got instructions on bench testing the Pertronix. What about just putting the points back in? Is it easy to install them? They worked before.
 

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Discussion Starter #18
Yes. Do you still have the original wire that passes through the hole in the side of the distributor?
Yes, I still have all the parts. It's easy enough to put in and I can gap them. I just don't have a dwell meter. Do I really need one?
 

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When I had my 65 coupe back in 68, I used a match book cover to gap the points. Worked every time.
 

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Discussion Starter #20
When I had my 65 coupe back in 68, I used a match book cover to gap the points. Worked every time.
I'm old enough to remember those. Don't know when the last time was I saw one. I also remember when a book of matches would drop out of the cigarette machine when you pulled the knob!
 
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