1973 Corvette, Engine not firing
Thread Starter
7th Gear
Joined: Dec 2015
Posts: 7
Likes: 0
1973 Corvette, Engine not firing
Hello to all.
this is my first post on the forum.
I have a 1973 fully stock Corvette. It has suddenly stopped starting after a couple of weeks of not being driven. The car turns over fine and everything seems to be working only the car isn't starting. After determining the engine is getting air and fuel, the spark became the next issue. I have replaced the points, condenser, rotor button and distributor cap without success. I then replaced the original ignition coil thinking the 40+ year old coil finally wore out. The car is still not starting. I am using an after market Flame-Thrower 1.5 ohm 40000 with an internal resistor coil. Still not sure if the car is getting any spark. Before all this happened, the car was running rough and the secondaries were not opening. This was the reason for replacing the ignition coil. Is there anything else I need to check or replace? Pretty sure the point gap is correct and spark plugs look good.
I really need some help on this as I am out of ideas.
this is my first post on the forum.
I have a 1973 fully stock Corvette. It has suddenly stopped starting after a couple of weeks of not being driven. The car turns over fine and everything seems to be working only the car isn't starting. After determining the engine is getting air and fuel, the spark became the next issue. I have replaced the points, condenser, rotor button and distributor cap without success. I then replaced the original ignition coil thinking the 40+ year old coil finally wore out. The car is still not starting. I am using an after market Flame-Thrower 1.5 ohm 40000 with an internal resistor coil. Still not sure if the car is getting any spark. Before all this happened, the car was running rough and the secondaries were not opening. This was the reason for replacing the ignition coil. Is there anything else I need to check or replace? Pretty sure the point gap is correct and spark plugs look good.
I really need some help on this as I am out of ideas.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Hello to all.
this is my first post on the forum.
I have a 1973 fully stock Corvette. It has suddenly stopped starting after a couple of weeks of not being driven. The car turns over fine and everything seems to be working only the car isn't starting. After determining the engine is getting air and fuel, the spark became the next issue. I have replaced the points, condenser, rotor button and distributor cap without success. I then replaced the original ignition coil thinking the 40+ year old coil finally wore out. The car is still not starting. I am using an after market Flame-Thrower 1.5 ohm 40000 with an internal resistor coil. Still not sure if the car is getting any spark. Before all this happened, the car was running rough and the secondaries were not opening. This was the reason for replacing the ignition coil. Is there anything else I need to check or replace? Pretty sure the point gap is correct and spark plugs look good.
I really need some help on this as I am out of ideas.
this is my first post on the forum.
I have a 1973 fully stock Corvette. It has suddenly stopped starting after a couple of weeks of not being driven. The car turns over fine and everything seems to be working only the car isn't starting. After determining the engine is getting air and fuel, the spark became the next issue. I have replaced the points, condenser, rotor button and distributor cap without success. I then replaced the original ignition coil thinking the 40+ year old coil finally wore out. The car is still not starting. I am using an after market Flame-Thrower 1.5 ohm 40000 with an internal resistor coil. Still not sure if the car is getting any spark. Before all this happened, the car was running rough and the secondaries were not opening. This was the reason for replacing the ignition coil. Is there anything else I need to check or replace? Pretty sure the point gap is correct and spark plugs look good.
I really need some help on this as I am out of ideas.
Welcome to our forum. The Pertronix Flame Thrower coils need 12 volts going to them; not the factory braided resistance wire that only produces 6 volts. Most people run a 12 gauge wire from the fuse block's IGN terminal to the + side of the coil.
Check the spark take the coil wire off and hold it next to a ground then have someone crank it. It should produce a fat blue spark at least 1/2" long. If it doesn't you have an issue somewhere in your ignition system.
You'll never see your secondaries open in your driveway as it takes a huge volume of air to open them. And the Quadrajets have a secondary "lockout" that prevents the secondaries from opening until the choke butterfly is fully open.
Check for a spark then get back to us.
Advanced
Joined: Sep 2015
Posts: 74
Likes: 6
From: oregon
I just went through this. I thought the points were set at .016, but they were not. After manually manipulating the points open and closed several times I reset them again at .016 and it fired right up. My points were used so the .016, yours being new you will want to set at .019. Good luck.
Burning Brakes
Joined: Sep 2010
Posts: 822
Likes: 82
From: Columbus OH
Sounds like you are at least willing to do the wrenching yourself! Great. Sometimes it helps to have a second set of hands and eyes on a problem to see what is going on. Where are you located? You might have another forum member that is nearby and might be able to help diagnose the problem. But the advice you have gotten thus far is sound.
Good Luck!
Good Luck!
Thread Starter
7th Gear
Joined: Dec 2015
Posts: 7
Likes: 0
Sounds like you are at least willing to do the wrenching yourself! Great. Sometimes it helps to have a second set of hands and eyes on a problem to see what is going on. Where are you located? You might have another forum member that is nearby and might be able to help diagnose the problem. But the advice you have gotten thus far is sound.
Good Luck!
Good Luck!
Thread Starter
7th Gear
Joined: Dec 2015
Posts: 7
Likes: 0
Welcome to our forum. The Pertronix Flame Thrower coils need 12 volts going to them; not the factory braided resistance wire that only produces 6 volts. Most people run a 12 gauge wire from the fuse block's IGN terminal to the + side of the coil.
Check the spark take the coil wire off and hold it next to a ground then have someone crank it. It should produce a fat blue spark at least 1/2" long. If it doesn't you have an issue somewhere in your ignition system.
You'll never see your secondaries open in your driveway as it takes a huge volume of air to open them. And the Quadrajets have a secondary "lockout" that prevents the secondaries from opening until the choke butterfly is fully open.
Check for a spark then get back to us.
Thread Starter
7th Gear
Joined: Dec 2015
Posts: 7
Likes: 0
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Thread Starter
7th Gear
Joined: Dec 2015
Posts: 7
Likes: 0
I just went through this. I thought the points were set at .016, but they were not. After manually manipulating the points open and closed several times I reset them again at .016 and it fired right up. My points were used so the .016, yours being new you will want to set at .019. Good luck.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
As the specs call for a dwell of 28 to 32 the point gap isn't critical at all because it should easily fire at any gap from .010" to .030". New points require about .019" so set them at .019" and check for a spark from the coil wire when held near a ground.
Burning Brakes
Joined: Jul 2015
Posts: 823
Likes: 57
From: Austin TX
This isn't a dwell problem unless the points aren't opening or closing at all. Like someone else said, the gap isn't critical in terms of the motor firing. Many of the potential component failures involved in the ignition system can be eliminated (or confirmed) simply by using an inductive timing light. I would start there. Are you sure this is an ignition problem? Does the carb have pump shot when you pull the accelerator linkage?