no spark
Thread Starter
Instructor
Joined: May 2007
Posts: 228
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no spark
69 427/400 changed distributor to pertronix because I could get no spark on TI. I can still get no spark. I have changed 3 ground straps and cleaned motor mount ground and neg ground strap. What can I check now?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
The TI quit, and the Pertonix won't work. Did you try another coil? And you did wire the Pertronix so it's bypassing the TI amp and going direct to the coil?
Thread Starter
Instructor
Joined: May 2007
Posts: 228
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I have 12 volts to coil and i bought a coil to match the pertronex. What do you mean by bypassing the TI amp. Do I need to unplug it? The wire that went to the pickup coil on the TI distributor is disconnected. I have the red wire to the positive side of coil and black to negative and 12 volts to coil but still no spark..
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
I don't know that the TI distributor and the Pertronix system are compatible. The TI distributor is a "magnetic pulse" system, not a 'points' system. It might be able to feed a signal to the Pertronix, but I would call Pertronix and ask them, just to be sure. The Pertronix was developed to replace a 'points' ignition system...they may never have considered that someone would try to convert a TI system with it.
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Instructor
Joined: Aug 2009
Posts: 119
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From: Demotte In
Hello
The wiring diagram is pretty simple- positive from battery to starter- starter to ignition switch- ignition switch to positive coil side- (resister) wire from starter to positive coil side-
Also, the distributor housing has to be grounded to the engine block - usually the hold down bracket holds the distributor as it is bolted into the top of the engine block- check for a good connection on the hold down bracket on the distributor and engine block.
You may have a bad ignition switch.
The coil is good if there is .6 to 1.5 ohms on the primary circuit ( positive to negative on the coil) and 8,ooo to 12,000 ohms on the secondary side (positive to center wire on the coil) of the coil.
Pertronix also recommends to increase the spark plug gap by at leat .005" from the factory .035" gap. I set my plugs to .040" and the car ( 68 327- 300 hp) does run better.
Good luck.
The wiring diagram is pretty simple- positive from battery to starter- starter to ignition switch- ignition switch to positive coil side- (resister) wire from starter to positive coil side-
Also, the distributor housing has to be grounded to the engine block - usually the hold down bracket holds the distributor as it is bolted into the top of the engine block- check for a good connection on the hold down bracket on the distributor and engine block.
You may have a bad ignition switch.
The coil is good if there is .6 to 1.5 ohms on the primary circuit ( positive to negative on the coil) and 8,ooo to 12,000 ohms on the secondary side (positive to center wire on the coil) of the coil.
Pertronix also recommends to increase the spark plug gap by at leat .005" from the factory .035" gap. I set my plugs to .040" and the car ( 68 327- 300 hp) does run better.
Good luck.
Burning Brakes
Joined: Jan 2010
Posts: 958
Likes: 88
From: Rexburg Idaho
If you had a TI you'll want to use the white wire coming through the fire wall just to the left of the dizzy. It is 12 V's off of the ign switch. There is no res. wire on the white wire it's a full 12 V's. If you need a drop down in voltage split the main harness that goes to the right side of the car on the fire wall behind the dizzy and you'll find a caped wire the went to the point type dizzy. It will have about 9 volts.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Has the car actually run on the [converted] points system yet? If not, since it was on TI system, your plugs may be gapped too large for the standard coil system. Plugs with TI get gapped to .045; plugs for points get gapped to .035...because of the lower coil potential voltage.
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
Try disconnecting the coil wire from the distributor and ground it near the engine block...does a a spark jump from the wire to the block? If so, your problem is in the distributor. If no spark, the problem is before the distributor, such as the coil or wiring to it.
You can also disconnect the spark plug wires one at a time hold it near the plug end and see if each has a spark jumping to the plug. Don't hold that by hand...get a tool made for it or you'll never forget the shock you get.
Several years back I had a problem where the engine would turn over and not fire. In my case the coil wire had a pin hole worn through the wire's jacket and the spark was escaping and grounding out against the metal shroud around the distributor. Replacing the coil wire fixed the problem.
You can also disconnect the spark plug wires one at a time hold it near the plug end and see if each has a spark jumping to the plug. Don't hold that by hand...get a tool made for it or you'll never forget the shock you get.
Several years back I had a problem where the engine would turn over and not fire. In my case the coil wire had a pin hole worn through the wire's jacket and the spark was escaping and grounding out against the metal shroud around the distributor. Replacing the coil wire fixed the problem.
Burning Brakes
Joined: Jan 2010
Posts: 958
Likes: 88
From: Rexburg Idaho
