What is causing my misfiring while driving ?

[Evan Frucht]

[QUOTE="Evan Frucht, post:
I have a weird feeling some other part of my electrical/charging system or SOMETHING IS CAUSING MY CONDENSERS TO REPEATEDLY BURN OUT... Is that possible even?

Yes
you just described a common thing with points, runs great, then things slowly get worse and old issues show up. You replace the points and then repeat.
Some cars will go for the longest time, others will haunt you. Unfortunately that is common. Its hard to say on the quality of the reproduced part rock auto sells as well. Is it up to the standards of someone skilled who rebuilds them on a distr machine? Not likely.[/QUOTE]
It doesnt really slowly get worse. It's sort of suddlenly and randomly goes bad out if nowhere and without even much running time between

 

[Evan Frucht]

The points are not slowly going bad, something seems to basically immediately fail after about 10 minutes of running every time. I thought maybe something is causing just my CONDENSER fail repeatedly.

 

[Evan Frucht]

I just got it running for about 20 seconds then it sputtered out...

Now it wont start

 

[RJRENTON]

[QUOTE="Evan Frucht, post:
I have a weird feeling some other part of my electrical/charging system or SOMETHING IS CAUSING MY CONDENSERS TO REPEATEDLY BURN OUT... Is that possible even?

Yes
you just described a common thing with points, runs great, then things slowly get worse and old issues show up. You replace the points and then repeat.
Some cars will go for the longest time, others will haunt you. Unfortunately that is common. Its hard to say on the quality of the reproduced part rock auto sells as well. Is it up to the standards of someone skilled who rebuilds them on a distr machine? Not likely.[/QUOTE]

IMO....
The capacity, or value, of the condenser (aka capacitor) is coordinated to the coil's primary winding current and inductive reactance. If the coil was changed to gain a higher spark voltage for more reliable ignition, the induced voltage that appears at the points, when they open, must be absorbed by the condenser. If this induced voltage exceeds the breakdown voltage of the condenser, it will eventually fail.
The sole purpose of the condenser is to absorb the induced voltage that can cause arcing at the points, impeding the charging of the coil's primary winding for the next opening, resulting in possibly erratic spark....ska "missing" under load.
There is no difference in the descriptive terminology: condenser or capacitor....they mean the same.
IF an incorrect ballast resistor is used (lower than specified value), the coil will draw an excessive amount of current, again, creating a higher primary voltage that the condenser must absorb when the points open.
NOS parts are still available on the internet.
Personally, I use NOS MOPAR OR Standard Motor Products "Blue Streak" points and condenser in my RS23V0A****** Prestolite dual point distributor. The Blue Streak points are ventilated and have the largest surface area for low resistance and longest life of almost all others commercially available.
Look to HALIFAXHOPS for nos Mopar distributor parts and service.
Just my opinion of course.
BOB RENTON

 

[Evan Frucht]

Ya I mean I'm really trying to diagnose this problem before just throwing parts at it.

I just swapped in another condenser that tested good with a multimeter.

No change...
Still cant get the car running

 

[Evan Frucht]

Turns out I actually forgot to put in the rotor for a second. But
The new condenser actually seemed to get the car started but after it warms up its starts misfiring and running kinda erratic
So I think the bad condesner was adding to my issues but not sure.


Now I'm thinking possibly spark plug wires are part of the problem. Dont know what else to check

The coil passes a multimeter test.

 

[RJRENTON]

Ya I mean I'm really trying to diagnose this problem before just throwing parts at it.

I just swapped in another condenser that tested good with a multimeter.

No change...
Still cant get the car running

How did you test the condenser? What multi meter did you use (FLUKE, SIMPSON, TTIPPLETT, some other brand like Harbor Freight)? Some are more accurate. What values did you get when you ran the test? I assumed you measured the coil's primary winding voltage both cranking and ignition on.
BOB RENTON

 

[Evan Frucht]

Yep back to square one. Basically symptoms are as follows

It starts,
Runs rough/erratically but only sometimes

It jumps from running fine, to missing and struggling for a second, then itl run good for another 30 seconds, then misses a few beats kinda stumbles for a sec, then sounds ok for 45 seconds of running, then dies out. Then when I start it back up I'll ocassionaly get a backfire.

 

[Evan Frucht]

How did you test the condenser? What multi meter did you use (FLUKE, SIMPSON, TTIPPLETT, some other brand like Harbor Freight)? Some are more accurate. What values did you get when you ran the test? I assumed you measured the coil's primary winding voltage both cranking and ignition on.
BOB RENTON

There videos on youtube. If the restiance grows when you connect a multimeter from terminal to housing. Its start at 10ohms and grow to 20 ohms over a few seconds and you watch the numbers raise or needle move.

 

[Evan Frucht]

Any ideas ? Would a video help of what It sounds like when its cutting out and dying.

It literally sounds great for 5 minutes, then it all goes to **** over a period of about 30 seconds....

Then I start it up again and it's the same back and forth. Running good, then terrible.

 

[Curiousyellow71]

Does your car still have the fuel filter sock on the pickup in the fuel tank?

 

[Evan Frucht]

I'm getting fed up enough I'm wondering if I should start replacing stuff

I have the big MSD red wires they are not very old
I have a new distributor
I've replaced the condenser a few times
I could replace my fairly new plugs which were trouble free for many miles before?
My coil checks out on a multimeter but I read sometimes it can check out like that but still have a weak spark?

Does this issue sound like it could possible more internal?

Or should I try replacing plug wires first?

I was even thinking of trying to go with electronic ignition I guess. Any thoughts on something like this https://www.ebay.com/itm/For-MOPAR-...-/324465438501?_trksid=p2349624.m46890.l49292

At the end of the day I want this car to be dependable. Electrical troubleshooting is not my expertise but I can manage I think if I have some guidance. I think I've done all the multimeter tests that have been advised so far

 

[Evan Frucht]

Does your car still have the fuel filter sock on the pickup in the fuel tank?

Yes, I thought about that early on as a possible cause for my issues but my fuel filter in the engine always seems to have gas in it so that leads me to believe I'm getting enough fuel feeding into to the carb.

I found this old thread that never really concluded properly but the original post sounds almost exactly like my problem.

Seems like stuff starts when the car gets warm... funny tho... he is running electronic ignition.

 

[Nevada dan]

I had a 413 the timing gear uses a woodruff key on the cam like yours
My key sheared and the gear would move
It would run good then stumble then run good then barely run pretty much like you described
While it won’t start check your timing it might not even be pointing at #1

 

[Curiousyellow71]

First, after it dies, check for spark at the plug wires.

I mentioned the sock in the gas tank because if that is plugged the filter could still have fuel in the filter but no flow. When you shut the car off the vacuum from the pump can dissipate allowing the filter unplug itself slightly and it will pump gas for a while till its plugged up again. I have had it happen.

 

[Evan Frucht]

I had a 413 the timing gear uses a woodruff key on the cam like yours
My key sheared and the gear would move
It would run good then stumble then run good then barely run pretty much like you described
While it won’t start check your timing it might not even be pointing at #1

Damn, how much diassably would be needed to diagnose that ?

 

[RJRENTON]

There videos on youtube. If the restiance grows when you connect a multimeter from terminal to housing. Its start at 10ohms and grow to 20 ohms over a few seconds and you watch the numbers raise or needle move.

I'm well aware of of how to test a capacitor/condenser with a VOM or Multi meter. I was inquiring as to your methodology and your results, which BTW do not test for capacity only if the condenser can hold or accept a charge and is not open or shorted.
BOB RENTON

 

[Evan Frucht]

I'm well aware of of how to test a capacitor/condenser with a VOM or Multi meter. I was inquiring as to your methodology and your results, which BTW do not test for capacity only if the condenser can hold or accept a charge and is not open or shorted.
BOB RENTON

Ya, I'm doing what I can with what I have. I think that one condenser may have been bad since swapping in my old MADE IN USA one seemed to at least get the car stated

 

[Evan Frucht]

I had a 413 the timing gear uses a woodruff key on the cam like yours
My key sheared and the gear would move
It would run good then stumble then run good then barely run pretty much like you described
While it won’t start check your timing it might not even be pointing at #1

The car is turned off and it just happens to have the timing mark on the flywheel right on TDC (it's at about the 2 degree mark to be precise)

When I pulled off the distributor cap the rotor is pointing to number 6

 

[mopar 3 B]

Yes
you just described a common thing with points, runs great, then things slowly get worse and old issues show up. You replace the points and then repeat.
Some cars will go for the longest time, others will haunt you. Unfortunately that is common. Its hard to say on the quality of the reproduced part rock auto sells as well. Is it up to the standards of someone skilled who rebuilds them on a distr machine? Not likely.

IMO....
The capacity, or value, of the condenser (aka capacitor) is coordinated to the coil's primary winding current and inductive reactance. If the coil was changed to gain a higher spark voltage for more reliable ignition, the induced voltage that appears at the points, when they open, must be absorbed by the condenser. If this induced voltage exceeds the breakdown voltage of the condenser, it will eventually fail.
The sole purpose of the condenser is to absorb the induced voltage that can cause arcing at the points, impeding the charging of the coil's primary winding for the next opening, resulting in possibly erratic spark....ska "missing" under load.
There is no difference in the descriptive terminology: condenser or capacitor....they mean the same.
IF an incorrect ballast resistor is used (lower than specified value), the coil will draw an excessive amount of current, again, creating a higher primary voltage that the condenser must absorb when the points open.
NOS parts are still available on the internet.
Personally, I use NOS MOPAR OR Standard Motor Products "Blue Streak" points and condenser in my RS23V0A****** Prestolite dual point distributor. The Blue Streak points are ventilated and have the largest surface area for low resistance and longest life of almost all others commercially available.
Look to HALIFAXHOPS for nos Mopar distributor parts and service.
Just my opinion of course.
BOB RENTON[/QUOTE]
I am not buying that explanation other than the part of buying quality parts.