im lost here! please help...

[waterdog]

i have been dealing with a little problem recently and though i found it... but NOT!! it keep coming back and the truck dies on me, my truck drives and runs fine for about 30 min then start to misfire and dies, then all i do is replace the condensor on the distributor and goes back to normal for about a day or a short trip, then misfire and dies!! so i go back under the dog house , replace the condensor, and it runs again!!! NOW when i say replace condensor means i put back the old condensor from yesterday, not a new one, i have been swithching condensors daily but use the same used condensors...my 4500rpm module is bypassed, i have a civy cap conversion, anybody have an idea what else should i be looking??? im just a bit lost here....only thing i do to make it runs is replace a condensor with an old one and works!!!!! i dont touch anything else....thaks!

[David Dunn]

First thought I have is your ballast resistor is bad and you have over voltage to the coil and it breaksdown. After cooling a while, it works fine until it overheats again. If the coil gets too hot to touch, check the voltage to the coil. Also check your charging system, if the voltage regulator is bad, it can cause the overvoltage too.

[waterdog]

Yes, i did check the ballast resistor and is within voltages as EI youtube video, what else could be???

[audiocontr]

bad connection near the ballast? You keep resetting the intermittent connection when you swap out the ballast? Vibrations back it apart

[David Dunn]

Did you check system voltage at high RPM?
Can you touch the coil after running the truck for some time?

[waterdog]

Is the ballast the same thing as condensor??... I never touch the coil after the problem, today i was listening at the truck running and i heard at the exhaust tip a very little almost not noticeable misfire constant...its like the misfire is there all the time and suddenly get worst and die.!!! Where is a good place to mesure voltage at high/ low RPM.??

[Jimm391730]

Is the ballast the same thing as condenser?

No. The ballast resistor is a silver "bell" looking thing under the dash. It's purpose is to reduce the voltage to the coil when the engine is running. When running, the positive (+) coil terminal should have about 17 volts from it to chassis (a volt or two either way is probably OK).

The condenser is pressed into the bottom of the distributor; it has one wire that connects to the points terminal.

What part are you swapping out each time?
What voltage do you measure at the + terminal of the coil when the engine is running? Does this voltage change when the engine dies?

[waterdog]

I swap condensor on the distributor.., i will re-check voltages at the coil with truck running.

[edzz]

did you work out the problem with the hot key?

viewtopic.php?f=14&t=7634&hilit=+key

[waterdog]

Yes, it was a loose connector, took the switch apart cleaned all good and reasembled... Problem solved.!

[waterdog]

The coil receive 19.6 volts at low RPM, and 23,8 at high RPM... Is that fine???

[David Dunn]

Re-read my 2 posts, and answer those questions.

[edzz]

I would check for voltage to the coil and compare the results under the following conditions. Voltage while starting (starter button depressed) and voltage while running. You should see a substantial reduction in voltage when the starter button is released. It is possible that the wires to the ignition switch are not attached to the correct posts. Did the current problem exist prior to the problem with the ignition switch?
Searching “coil resistor” finds many posts some that may lead clues. Two that stand out are the following posts Jim made. I did not review all of the results of that search.

viewtopic.php?f=14&t=7685&hilit=coil+resistor

Check the voltage at the + terminal of the coil; if it is much more than 17-18 volts then the ballast resistor may be shorted (or possibly the ignition switch has been mis-wired). IIRC the Pertronix won't take more voltage than the low 20's; without the ballast resistor the voltage could be 28 and this is likely to kill the Pertronix.

viewtopic.php?f=14&t=7613&hilit=coil+resistor

If you can touch the resistor and hold your fingers on it for 5-10 seconds then it is not too hot. The resistor's purpose is to "burn off" excess voltage by turning it into heat.
Cranking the engine to get it started draws the battery voltage down and this is the time when a good ignition is critical. So the ignition is designed to run on 17-20 volts as might be seen during a hard cranking. Once the engine starts, the alternator kicks in and starts charging the batteries at ~28V which would cook the ignition system - hence the ballast resistor is needed to reduce this voltage. When you push the starter button, the ignition is fed directly from the battery and when you release the button then the ignition is fed through the ballast resistor.
As best I know the 4500 RPM module interupts the current flowing to the coil (to stop the ignition completely) if the speed goes up too far; it doesn't "short" out the coil. So this would not heat the resistor more than normal; it actually would decrease the heat generated.
If water or spit sizzles when touched to the resistor, THEN it is too hot. They are really designed to be able to get quite hot without damage. The ballast resistors are pretty bulletproof and don't fail easily.
But if the smell is new then obviously something has changed. Check the battery charging voltage (should be 27-29 volts), the voltage on the + side of the coil to chassis (should be 17-20 volts). Have you changed coils lately? Is the point dwell correct (check this even with a Pertronx) as this could allow too much current through the coil? Is your coil getting too hot to touch?

[David Dunn]

IF there is a condensor (as he has said he keeps exchanging) you cannot have a Pertronix, the 2 are not used together.

With the lack of some information, I am thinking he has a charging system problem... the BR can do it's job but if the voltage regulator isn't, there is a possibility that it is charging at over 28v and the BR is reducing the voltage the right percentage, but is the increase across the board is more than the coil can handle, especially if it is an original coil and has been subjected to overvoltage for a while. It may have worn a slow death.

Unlike alternators that reach max power at 1500ish rpms, generators will keep putting out more voltage with more rpms, and if unregulated can produce over 33 volts, hence why the voltage at high rpm is so important.

Almost all vehicles with a coil has a BR bypass at crank over to give full voltage at starting. The Pertronix for 24v systems are rated to a max of 28 to 29 volts.

[waterdog]

No petronix here.....