Today's problem is..

Hi everyone, I am working on my dad's 64 convertible, and I have been chasing this problem for a while now, the car idles great when cold, but once everything warms up, it starts strugling to idle, and then dies, this happens in park or drive. So far I have checked fuel pressure, fuel boiling, choke operation, (carb has been replaced twice), checked timing and advance, checked for spark when the engine was stalling, it had a good strong spark, checked fuel cap to make sure it was venting, and have gone over the engine several times trying to find a vacuum leak, and have plugged all vacuum sources trying to find a leak, the engine only shows 15HG of vacuum at idle, but I cannot find a reason for it to be low, I really am running out of ideas here. Any help or things to check will be greatly appreciated.

Chris

BarryK

did you check the coil? Coils that start to go bad tend to show up their problem when they get hot.

15" vacuum might not be a problem, depends on the motor and cam.
what motor is in the car. My '65 L76 with the stock 30-30 cam only gives me about 13-15" vacuum.

bb62

You are not being specific about the engine. But it may be as simple as the plugs. My 435 does much the same thing when it gets hot outside. AC43s (which I run) are standard equipment but suffer when under idle for long periods of time. AC45s as a hotter running plug may fix your problem. If the car runs fine in cool weather, it is rarely the carb. As noted by another poster, it could also be the coil.

vetarun

i would touch the coil and see if it's super hot after it dies. you balast could be bad.

Today's problem is..

The car is the original 327 engine still, but had the 30-30 cam swapped out for an L82 cam as he wanted something a little more tame, the coil is fairly new as it was switched over to a pertronix system a few months ago, I realize this doesnt mean the coil is good, but will the coil being hot be my only clue as to it might be going south, is there a way to test it?

Thanks,
--Chris

vettes1st

You have found the problem when you said Pertronix. Change back to points or if you just have to have that Pertronix, get a new one.

MikeM

BarryK

errrr......... I'm not saying a word...........

63C2splitter

I have an electronic ignition in my car, but haven't had any problems with it dying when hot. However, that is a typical indication of one that is going bad (not just Petronix). It also sounds similar to what you would experience with a fuel line vapor lock - is the fuel line against the block or exhaust? good luck solving the problem. Trouble shooting the ignition would be your first step in my opinion.

Dave

Today's problem is..

Thanks everyone, I am going in the morning to check the coil to see if its hot when the engine dies, I checked for vapor lock, but when it dies, I flipped the throttle and two fine streams of fuel shot out when I did, I hope its not the pertronix as it is fairly new, but its the first one I have ever dealt with.

buns

By cutting the ignition switch out of the circuit, it can easily be determined whether or not the coil is defective or whether the fault lies with the ignition switch.
A wire should be connected to the terminal of the coil to which the battery wire is normally connected, Fig. 56. This temporary connection jumps the ignition switch. If the trouble is eliminated when the engine is started, it is obvious that the ignition switch was the offender—not the coil.
Simple Ignition Coil Check
In the absence of any testing equipment a simple check of the ignition coil can be made as follows: Turn on the ignition switch with breaker points closed. Remove the high tension cable from the center socket of the distributor cap and hold it about 3/8" away from a clean spot on the engine. Then open and close the breaker points with an insulated screwdriver. If the coil and other units connected to it are in good condition a spark should jump from the wire to the engine. If not, use a jumper wire from the primary terminal of the distributor to the engine; if the primary is in good condition a spark will occur.
Simple Test for Open or Grounded Circuit
To test for an open circuit in the primary winding, disconnect the distributor wire from the coil and use test points (or clips) as shown in Fig. 57. If the bulb lights the coil is okay.
To test for an open secondary winding, put one test point in the high tension terminal socket and the other one at one of the primary terminals. If the secondary winding is not open, the lamp will not light but tiny sparks will be noted as the test points are rubbed over the terminals. If the secondary winding is open, no sparks will occur and the lamp will not light.
All ignition coils with metal containers used on passenger cars can be tested for grounded windings with a 110-volt test lamp. Isolate coil by disconnecting wires from it. With one test point in coil tower and the other on paint-free outside shell, defective coil will be indicated if bulb lights or if tiny sparks appear when test point is rubbed on outside shell, Fig.58.
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electrocuted smiley -

OC-1

My car ran fine with points and a new coil, then decided to replace the points with a Pertronix. Seemed to run ok for a short while then it kept stalling. I don't know if my new coil was bad or went bad but a new Pertronix coil solved the problem. Directions say you can use your standard coil but I wonder if there are compatibility issues with some coils and Pertronix ignitions?

Today's problem is..

This could very well be the case, the coil on the car is not a pertronix brand coil.

JohnZ

How is the Pertronix unit wired for its power source? The Pertronix module requires a full 12 volts for proper operation, but a stock coil operates at reduced voltage (from the ballast resistor). If the ballast resistor is still in the circuit to the coil, the Pertronix red wire should NOT be connected to the coil (+) terminal. See the diagram below for Pertronix connections with stock-type coils or with aftermarket coils that require 12 volts.

MikeM

Somebody posted awhile back that some/many coils with US name brand coils made offshore are not compatible with the Pertronix according to Pertronix. I can barely spell Pertronix, let alone own one.

Today's problem is..

I checked the coil first thing this morning and it was pretty hot, I replaced the coil and the car ran and drove great today. I will check over the wiring for the pertronix when I get a chance, I know the red lead is wired to the pos. side of the coil, so where would the ballast resistor be located in the wiring?

Thanks,
--Chris

JohnZ

The ballast resistor is mounted to the firewall inboard of the master cylinder. It's fed from the ignition switch by an 18-ga. black/pink wire that comes through the grommet with the wiper motor wires, and the other end of the resistor has an 18-ga. black/pink wire that goes to the coil (+) terminal. You want the Pertronix red wire connected to the end of the resistor that has the wire on it from inside the car (12 volts), and the wire to the coil connected to the other end of the resistor so the coil sees the resistance-reduced current it requires.