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Discussion Starter · #1 ·
I have a 65 with a 200cui L6 with a no start problem. I have a good hot spark from coil but not to plugs. I’ve put a new cap, rotor, plug wires and spark plugs on and still no spark. I’ve taken the primary coil wire and held it against ground and get a good hot spark. But when I hold spark plug 1 against ground I get nothing. Any ideas? Thank you!
 

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Points and condenser, or electronic? If P&C, could be a dead condenser.
 

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Discussion Starter · #4 ·
I have two rotors: one new from Napa and the one that came with car. No go on either.

If the condenser was bad, I shouldn’t have spark out of the coil either right? Because I have a good spark out of coil when I hold the output of coil to ground.I should mention the points and condenser I installed a couple months ago and had the car running since then.
 

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I have two rotors: one new from Napa and the one that came with car. No go on either.

If the condenser was bad, I shouldn’t have spark out of the coil either right? Because I have a good spark out of coil when I hold the output of coil to ground.I should mention the points and condenser I installed a couple months ago and had the car running since then.
Alternator feeds the coil. Coil feeds the distributor and everything inside it.
 

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After the coil wire, the cap, rotor and plug wire are the ONLY thing between the coil wire and the spark plug, period. If there is a short to ground in the secondary system that can lose your spark as well. Like a shorted rotor, although if you have two it is unlikely. So, is the carbon button in place inside the cap still? Pull a plug and put it in the wire and hold to ground while cranking, maybe it has a weak spark you are not seeing?
 

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Unhook your condenser and retry to start
Electric takes path of least resistance
Almost no resistance at coil wire.
High resistance through wires to plug
Shorted condenser takes fire away from plugs
 

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What's the rotor look like? Maybe you've got the wrong one? The i6 rotor looks different from most v8 rotors.

I'm wondering if the rotor's not making contact with the button on the top of the cap and you need to bend the tab up, or if maybe you managed to get (2?) bad caps. Can you put your ohm meter on beep and make sure you've got connectivity between that button on the inside and the connector on the top?

Typical i6 Load-o-Matic rotor for reference:
802451
 

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Make sure the end of your new plug wires actually engages the tip of the spark plug. I had some new wires that liked getting pushed up into the boot instead of engaging the spark plug tip. I had to redo them several times to get it right….took Me awhile to figure why my new wires caused my engine to fire on 5 of 8 cylinders.
 

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Discussion Starter · #12 ·
What's the rotor look like? Maybe you've got the wrong one? The i6 rotor looks different from most v8 rotors.

I'm wondering if the rotor's not making contact with the button on the top of the cap and you need to bend the tab up, or if maybe you managed to get (2?) bad caps. Can you put your ohm meter on beep and make sure you've got connectivity between that button on the inside and the connector on the top?

Typical i6 Load-o-Matic rotor for reference:
View attachment 802451
802472
Can B KB fjv vin nn
these are the two I have. The one on left is from Napa (new) the one on right is what came with car. I have had the car running with the one on the right.i
 

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Discussion Starter · #13 ·
What's the rotor look like? Maybe you've got the wrong one? The i6 rotor looks different from most v8 rotors.

I'm wondering if the rotor's not making contact with the button on the top of the cap and you need to bend the tab up, or if maybe you managed to get (2?) bad caps. Can you put your ohm meter on beep and make sure you've got connectivity between that button on the inside and the connector on the top?

Typical i6 Load-o-Matic rotor for reference:
View attachment 802451
802475

these are what mine look like. The one on the left is from Napa (new) the one on the right is what came with the car and have had the car running with before.
I am getting continuity thru the cap. I also get 5.7kohms with the primary coil plugged in to cap and measuring from inside cap to end of primary coil wire.
Any other thoughts?
 

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The big wire that comes from the center of the coil is the secondary wire, all the spark wires are part of the secondary. The primary wires are the small wires that come from the distributor and ignition switch. The primary side of the coil is 12v, the secondary side is maybe 20,000-30,000 volts, the side that shocks you.😁
Did you verify that the center button in the cap makes contact with the top of the rotor?
 

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I would recheck the gap on your points, and put the old condenser in and see what happens.
 

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If you have a strong spark out of the coil, your points and condenser are not an issue.
Hu? I've never tried to get spark straight from a coil bypassing the condenser. The coil builds energy up in the condenser, and when the points open it's looking for a ground, then when the rotor passes a terminal on the rotor cap it grounds through the spark plug making a spark. It could absolutely be a bad condenser or dirty points causing no spark.
 

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Hu? I've never tried to get spark straight from a coil bypassing the condenser. The coil builds energy up in the condenser, and when the points open it's looking for a ground, then when the rotor passes a terminal on the rotor cap it grounds through the spark plug making a spark. It could absolutely be a bad condenser or dirty points causing no spark.
Read the op's description of the problem. He had spark at the coil.
Also, the coil does not build energy in the condenser. The condenser acts to absorb the primary voltage when the points open therefore keeping them from arcing.
My point was that if he already had good spark from the coil, then his points and condenser are fine.
 

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Ok, so you merely insured the coil wire was fully seated. How did you fix the rotor center strip not contacting the carbon?
 
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