Can't seem to find the problem

[Purdy Swoft]

I use an internally resisted 3.0 ohm Pertronix Flamethrower coil on my roadster. I have ran this car 12 volts positive ground for the past five years without one minutes trouble. This coil is epoxy filled and has NO oil to leak when mounted with the wire connections at the bottom as model A coils are mounted. This coil needs NO ballast. If you continue to have problems, the ballast MAY be connected to the wrong side of the coil.

[middletown]

I'm gonna go a different direction on this one. Have you checked for a restriction in the fuel at the tank? Rust and garbage can build up at the outlet and still allow enough fuel though to run but as more fuel demand (time or acceleration) is added the car will begin to starve for fuel. Allowing the car to idle or sit momentarily often temporarily helps the issue so as you worked to solve the problem fuel seeped by the blockage and filled the bowl and line so when the next test drive started all seems fine. Since the car is going lean the choke would "seem" help out and a lean mixture is going to lead to higher operating temps. To check this disconnect the fuel line at the carb or somewhere below the tank and using a rubber tipped air nozzle connected to your air compressor carefully blow back up into the tank to disperse the blockage. If it works clean the tank or ignore it until it happens again; if you really get it cleared it usually takes along time to build up again.

Just a guess,

Good luck,

Joe

[John Stone]

I have solved the problem. It was explained in an earlier post.

Thanks for all the ideas.

John

[Tony S,Fl.]

Had the same problem . Unscrewed the ignition (large coiled wire cover from the ignition switch to distributer) 2 turns .Seems as the enginewarmed up expansion caused a short in the distributer where it butts against the contact causing a short. Tony

[Tony S,Fl.]

Unscrew the ignition cable from the distributer 2 turns. Heat causes expansion. Worked for me. Tony

[MAG]

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Originally Posted by Purdy Swoft

'.....the ballast MAY be connected to the wrong side of the coil.

Inquiring mind wants to know:
What difference does it make which side of the coil the ballast resistor is connected. And why?

[Tom Wesenberg]

12 volt conversions are no big deal, but I would stick with 6 myself.

You said the points closed up. The means the dwell would increase greatly, which will overheat the coil. Normally current only flows about half the the time or a bit less in the Model A coil. As the points close up that means the current is flowing for a longer period of time vs. the off time (points open).

My first thought was the gas is boiling in the carb and maybe the fuel line. What kind of gas are you using? And,hot hot is the outside air?

[Purdy Swoft]

One side effects the voltage that enters the coil, the other side effects the voltage too the points. Too much voltage to the points burns them out pretty quick. Model A didn't use a ballast. The internally resisted coil that I use doesn't need a ballast and appears more original.

[Purdy Swoft]

Just to add to my previous post, if a ballast is used it would need to be connected to the side that feeds the points. I don't need to use a ballast but I would think that it would connect to the RED wire side.

[John Stone]

These are my thoughts on the previous posts:

He had original points and it was actually my distributer. I must not have gotten the point post screw tight. My bad. As you all know, closed up points can act like a bad coil which did confuse me yesterday morning until I found it.

Yes, initially he did have a load of alcohol gas which again clouded the issue. I added a generous amount of MMO to eliminate that problem.

Yes, I did make sure the ignition cable was not screwed in to far.

I believe you should put the ballast resistor on the feed side of the coil. The coil is 6v so you would want it operating that way. 6v will go to the points. My thoughts.

Another thing I found initially was a cracked distributer body and the cap didn't look very good where it contacted the rotor. I kept thinking I had found the problem but it would come back after 3 miles.

Still the bottom line was the bad coil on Monday with the closed points causing me a restless night. LOL

Thanks again for the help. -- John

[steve s]

Originally Posted by MAG

Inquiring mind wants to know:
What difference does it make which side of the coil the ballast resistor is connected. And why?

I'm with MAG, and his earlier description. It can't matter which side of the coil a resistor is on.

If you have a problem with which component the electricity gets to first, just switch between thinking of current as defined in physics books (direction of positive charge flow) and current defined as flow of electrons. They go in opposite directions, so you can pretend it's going in whichever end you prefer--but the car doesn't care.

Steve