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302 issues

2K views 14 replies 6 participants last post by  Ivy66GT 
G
#1 ·
I have a 1968 Coupe that I have had running for about a month now. Edelbrock 750 performer (jetted way down) with an Edelbrock manifold. It ran fine untol 2 days ago. I pulled it out of the garage and let it idle about 2 minutes, then shut it off to work on the interior. about 1/2 hour later I try to fire it up and it won't run. When I first crank on it, it fires for about a second then dies. Each time I turn it over, it fires for about a second then dies. If I pump the gas before starting it will rev slightly before dying. I checked the fuel filter = good. I checked the line all the way to the carb and I am getting fuel. I pumped the throttle and saw fuel coming from the primaries. Is it a spark issue? What do you think?
I am stumped
Thanks!
Gordon
 
#2 ·
Basics....you have fuel. Spark? Timing?

Just pull a spark plug. Reattach wire and have someone crank the motor over as you ground the threads of the plug. You should see a spark.

If not, check that the points are opening.....could be many other things, all minor.
 
#3 ·
Is it dieing when you release the key to the RUN or IGNITION position, if it is then you have a problem with the resistor wire under the dash, I think it is pink. This means it stays running if you hold the key in the START position (cranking). Post your results. Good Luck.
 
#5 ·
My Guess: You have a faulty ignition switch. Works fine in the "START" position, but not the "RUN" position.

Try this: Attach a jumper wire from the positive battery post directly to the positive coil post. Then start the car -- I bet it runs fine.

Note: This is a diagnostic test, NOT a permanent fix. So shut-off the engine, then remove the jumper wire ASAP.

BTW, do you have a stock 6V coil & points-type distributor?
 
#6 ·
The "pink" resistor wire is just an insulated wire. I doubt it's suddenly gone bad.

But maybe somehow it became disconnected. Have you been doing any under-dash wiring work? Maybe a new radio?

FWIW, this is the "pink" wire:

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#7 ·
The ignition system gets power from the starter solonoid 'I' when you are cranking (starting) the engine this gives it full battery voltage, when you release the key to the RUN position, then the solonoid releases and the ignition switch supplies battery voltage to the pink wire (which is like a ballast resistor and drops the battery voltage to about 6-8 volts, this keeps the points and coil from burning up, and it then connects to a plug connector on the firewall, then too the coil + lead, you need to check with a voltmeter or DVM and see where you are missing the voltage. If anything like the radio or heater works with the ignition key in the RUN position, then the ignition switch is okay, and you either have a bad pink wire on a bad connection between the ignition switch and the coil + terminal. Post your results. Good Luck.
 
G
#8 ·
That was the problem! I put a jumoer from the battery to the coil and she runs like a champ..
So how do I repace the wire? Another question. There is a ceramic resistor at the front of the block. It's about 1/2" square by 3" long. Spade terminal on each end, and inside has a spring wit the terminals attached to each end. The ignition wire comes out of the firewall and attached to one end. The wire on the other end goes to the coil. Could this be bad? What do I replace it with if it is?
Thanks for all your help gents!
Gordon
 
#11 ·
T...There is a ceramic resistor at the front of the block. It's about 1/2" square by 3" long. Spade terminal on each end, and inside has a spring wit the terminals attached to each end...
That is very non-original ballast resistor. The 'spring' is actually the ballast resistor. That thing may well no long work. Instead of something like that Ford used the pink resistor wire shown above which should plug into your wiring and be mostly hidden in the wiring loom. You can buy the pink resistor wires nearly anywhere including your local NAPA.
 
#9 ·
Do you have a stock 6V coil & points-type distributor?


Some aftermarket coils & distributors require 12V. But the pink wire only provides about 6V.


That is, make sure you actually need the pink wire.
 
#13 ·
Yes, the pink wire acts as a resistor. It provides enough resistance to reduce the voltage to about 6V.

So there's no need for an extra inline resistor -- unless the pink wire was removed.
 
G
#14 ·
So I dropped the iginition switch out of the dash, pulled a little on the pink wire, and voila,she fired right up. So it comes down to a bad connection..... Thanks to all of you for pointing me in the right direction!plus1..gifplus1..gif
 
#15 ·
That's good that you found the problem. You need to unplug that wire and plug it back in every 40-50 years or so to keep the connection clean and working. :)

All wire has some resistance but its usually something like 0.01 Ohms which we would normally call zero. Ford just made the pink wire out of a different metal so that it has the correct 1.35 Ohms resistance in its few feet of length. The 'spring' in your funky ballast resistor is a different kind of wire again so that it has a similar resistance in only a few inches of length.
 
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