Pertronix in, won't start

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I'm getting no spark from the coil wire to dizzy.
I have 12 v going to coil.
I get spark from (-) coil terminal to ground when ON

You're saying that my coil is burnt open on secondary side?

This is ridiculous. Seriously... what can go wrong with attaching an ignition wire and 2 wires from the pertronix? Oh, and i've grounded the dizzy as well.

The unit must be defective, no?
 
Yep, I treid that, it didn't work. I also tried it with the old ballast resistor attached as well.

Assuming the pertronix unit may be toast... Guess this weekend i'll throw the points back in, see if that works...

This sucks. :(
 
Not to repeat too many times what folks are saying but...


1. Disconnect the pertronix wires completely from the coil.

2. Connect the coil as shown in my TAD (Tequila Aided Drafting) drawn pic. I would just connect the + side of the coil straight to the battery so you KNOW it has good +12V

3. Make SURE the spark plug is grounded well and place it where you can see it. A simple clip lead to the ground electrode to a bolt head will do.

4. Now, each time you QUICKLY touch and release the wire connected to the - side of the coil to ground, you should get a nice fat blue spark.

No sparky? Double check all connections, try again.

No sparky? Bad coil.

Testing Primary Side of Coil

You can measure the resistance of the primary side of the coil by setting your VOM to it's lowest OHM setting and measure across the + and - posts on the coil. Typical readings will be 1.2 to 3.4 ohms. Your meter needs to be pretty accurate at low ohms to get a valid reading. Most cheaper VOM's will not give an accurate reading. The point is to see if it's open. No reading means throw the coil away.

Testing Secondary Side of Coil

Measure from the spark plug tower to the - side of the coil. This reading should be higher than the primary side. Again an open means throw it away. Typical readings are 6.5 to 8.5 ohms.

The values given are for typical coils your coil may be different. If you can measure them post up the results.
Sparky.webp
 
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Coolerman, thanks so much for the advice, I GREATLY appreciate your time. Thanks for the drawing, it made me want to drink some tequila... ;)

I'm at work again so I'll get some results later on this afternoon!

Pinhead: What would be wired incorrectly? I've double/triple checked that all my connections are solid, I have a 12V ignition going in, and my pertronix leads going to their respective terminals. I tried using my old ballast resistor that was apparently working with my old nippon denso coil, but, nothing happened.

12V going to resistor, other side of resistor going to + side of coil terminal.

One last ????? about the original wiring:

Coming from the firewall, I had my ignition wire @ 12V, and another wire @ about 6V.

1)The 12V wire was connected to the ballast resistor, which lead then to the (+) terminal.
2)The 6V wire was connected to the (-) side terminal along with the primary wire from the distributor

Anyone know what this second 6V wire was?!
 
LOL

Typically the 12v lead to the coil is only 12 when you have the key
turned and the starter is turning.

After it starts the 12v drops away. and the 6v should remain to power your coil.

Wired as you described seems incorrect to me.
both the Momentary 12v and the constant 6v should be attached to the + side of the coil.

nice post Coolerman,
I particularly like the 8x12 color glossy's
Good luck.
 
GreenBomber said:
What would be wired incorrectly?

One last ????? about the original wiring:

Coming from the firewall, I had my ignition wire @ 12V, and another wire @ about 6V.

1)The 12V wire was connected to the ballast resistor, which lead then to the (+) terminal.
2)The 6V wire was connected to the (-) side terminal along with the primary wire from the distributor

Anyone know what this second 6V wire was?!
Click to expand...


I don't know the specifics for wiring a Pertronix, but my understanding is that it has two components: a pickup that goes inside the distributor and an ignitor that goes between the coil and distributor. The ignitor needs 3 connections: 12V power (from the + side of the coil or key side of the ballast resistor), a wire to the - side of the coil and a wire to the distributor pickup. There could be more wires than this, but this is a minimum.

There is no "6V wire" on cruisers. You might get 6V in a circuit, but only by measuring in between two resistors in series that have equal resistances (a voltage divider).

What are the color codes of the wires in question? There should only be 1 wire connected to the - side of a cruiser and that goes to the distributor. If you have a tachometer, there may be another wire.
 
Pin_Head said:
I don't know the specifics for wiring a Pertronix, but my understanding is that it has two components: a pickup that goes inside the distributor and an ignitor that goes between the coil and distributor. The ignitor needs 3 connections: 12V power (from the + side of the coil or key side of the ballast resistor), a wire to the - side of the coil and a wire to the distributor pickup. There could be more wires than this, but this is a minimum.

There is no "6V wire" on cruisers. You might get 6V in a circuit, but only by measuring in between two resistors in series that have equal resistances (a voltage divider).

What are the color codes of the wires in question? There should only be 1 wire connected to the - side of a cruiser and that goes to the distributor. If you have a tachometer, there may be another wire.
Click to expand...

Thanks again for the reply Pin_head.

All I have is the pertronix pickup which goes into the distributor and "replaces" the points and condenser. This attaches directly to the pertronix coil.

They call the pickup "Ignitor" so thats why I was calling it that.

As far as I know, I do not have an actual ignitor which goes in between the coil and the distributor.

The wiring may not be stock, but, I have a purple wire with a white stripe which holds 6V when the key is ON, and my ignition wire which is pink.

Since this coil is a 12V coil with a 1.5ohm internal resistance, it was my understanding that I was to use a 12V full time ignition wire.

I asked Mark for the entire "kit" I would need to convert over to an electronic ignition with my setup, and this is all I recieved.

Any other insight would help... :idea::idea:
 
Reading through several pages of Pertronix pages over the last few days, I feel that I have the unit set up correctly, and I do not need an external ignitor with this system!?

When I get home, Ill check the coil as Coolerman suggested...
 
start position voltage

Forgive me if I skipped some and you already mentioned this but.

Is the 12 volts available when the key is in the on position but also when the key is in the START position? You need both-start for starting and on for running

Quick check it by disconnecting any pos wires from the coil pos and run a wire straight from the batt positive to the coil positive then crank it over--you'll have 12 volts no mater what the ignition sw circuit is doing then.

Since you are working alone I thought maybe that you haven't checked while cranking if that is the case you will have 12v with the key on but nothing at the coil pos with the key turned to crank it

The key point is that while you are cranking it only the "start" pos is powering the coil ---the wire from the on pos goes dead so if the start pos is dead you have nothing while cranking

does that make sense?
points.webp
 
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BSmith, yes, I actually just tried that.... Wire directly to + side of coil from battery, and jumped the starter lugs... Nothing! I even checked the voltage, and it stayed at 12.5V (battery voltage).
 
OK... I did the things Coolerman said...

I connected the coil (+) to a wire connected directly to the battery pos
I connected the coil (-) to a wire connected directly to the battery neg
Put a spark plug in, and tried grounding it, and no spark.

The ohm reading was 2.5 ohms between the pos and neg terminals on the coil.

So, If I have the coil connected directly to the battery, and not getting a spark on a spark plug, I am assuming the coil is bad?
 
Here is a tip Greenbomber, hook yor timing light up like you are going to set the timing. Drag the T.L. into the cab. When you go to turn the motor over hold the T.L. trigger down. Flash, flash, flash. If the T.L. wires are too short you can duct tape the T.L. trigger and set it down so you can see the light. IDK, an alternate method. Beats jumping the starter but introduces the possibility of getting beffudled by a faulty timing light. Another one, that petro has to close a circuit like points (I mean no way around it since threre is only two wires, right guys?) So alligator clip a voltmeter to the disconnected petro wire ends, set the meter for continuity and hand spin the dizzy to see if the petro itself opens and closes 1 or 0. Simple?
 
neg wire

You also have to touch the neg wire and remove it then repeat
you should get a spark when the circuit is broken

it is the loss of voltage in the primary that creates the surge in the secondary coil to produce the spark

if it doesn't work then, then yes it sounds like the coil is shot

"Another one, that petro has to close a circuit like points" from above

Yup, your petro is just basically acting as points opening and closing the circuit

what about the - side is it going to your petro? earlier it sounded like you had 12v going to one side and 6 volts to the other?

but since you tested the coil independently I don't know what to say sounds like it is bad unless you never worked the neg wire on and off (like a set of points would)---have you tried your old coil same method to the battery?
 
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Its possible you have a defective pertronix. that sucks, bad right from the start. I dont recall having used the small grounding wire, so that shouldnt be an issue.

can you get spark out of the coil at all? as in put the 12v switched on the + side, with the key on, run a spark plug wire to the block (clean metal) with a slight- 1/16 gap) and then ground and unground the coil - side should net a spark...
 
Thanks for the replies again,

I made sure that I was "breaking" the circuit when testing the spark with the spark plug. I wire brushed clean a part of the block, and tested w/ a voltmeter that it was a clean ground.

No sparky.

This was with wires directly attached to the battery.

My ignition wire has a full 12.5 V so It would work the same, just easier than turning the key everytime I want to check it...

Next up, I'll try testing the circuit of the pertronix, but, It looks like the coil is bad since I'm not getting any spark!? Right?!

I tried the timing light method, no light coming through the timing light...
 
Coil

Yup

looks like we shot down the coil, thats a problem but I wonder if thats the cause or a symptom, still progress is progress!
 
.... Two words: Ih8wiring ... :D
 
yup

It's part of my job and not always a joy!

I dont know the pertronix unit but the OEM should be able to tell you how to test it without damaging it

I don't shoot into anything with a meter unless I know what's inside
 
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