Is the condenser in the distributor and the capacitor mounted on the coil the same part?
Meaning could you order the same part number for both?

 

Both are capacitors. They should have part numbers.

 

Capacitors are rated by their capacitance (microFarads) and operating voltage. The coil and points capacitors could be the same, but you'd need to compare part numbers, specs, or actually measure the capacitance to know for sure.

 

"Condenser," in this context (as opposed to the condenser in your A/C system), is just an old-fashioned term for a capacitor. Go read any technical literature from the early days of radio and the likes of Lee De Forest, Edwin Armstrong, Guglielmo Marconi, and others at that time, and the term "condenser" is used all the time while the term "capacitor" is never seen. "Capacitor" began to replace "condenser" in electronics terminology in the mid-1920s. (I at one time taught a course on all of this.)

 

Appreciate the clarification.

 

No , they are not .
The ignition condenser inside the distributor and the radio interference capacitor mounted on the coil are not the same .
They are both of different microfarad ratings , and have different part numbers .
They are not interchangeable .

 

What's important is the microfarad (μf) rating stamped into the condenser and capacitor shells. Radio suppression capacitors are interchangable between brands. Therefore, no part numbers are needed.
Despite contact point distributors also sharing identical μf ratings between brands, if I recall correctly, GM condensers were incorporated within the contact points assemblies. Making them not interchangable with those of Ford, Chrysler, Mercedes etc...

 

I am in the process of converting my ignition to PerTronix II with the Flame Thrower II coil. The capacitor on the coil mounting bracket looks like the original one from 1972. I cannot find anyone that lists that part and I can't find a p/n on the capacitor. I can get the condenser for the distributor so I ordered one hoping they were interchangeable. My question now is; if the capacitor on the coil is for radio interference do I still need it since I have also installed new 8mm suppression plug wires?

 

Probably not. You can still get the radio suppression caps at your local parts store.

 

I got one from my local Napa a couple of years ago but it's a little longer than the factory one. Inline tube sells one, pt#12835 for $19 They also have the correct one for the GM external voltage regulators with the spade terminal

 

I am not an electrical engineer, but I make electrical engineers cry.
With that said, the coil capacitor is not strictly necessary. Try running without it. If you have bad radio interference, then put a capacitor on the positive side of the coil. I'd say it would be worth trying a distributor capacitor as a test.
Sure, they're not the same, but the job the one on the coil is performing is not very critical, nor sensitive. So any capacitor will help dampen noise on that side of the coil. The sizing of the capacitor on the points is critical.
The only thing to remember is the body of the capacitor on those "one wire" capacitors is the ground side, so the body has to be grounded well to the engine.

 

Thanks for the info. I will try running without the coil capacitor. I hardly use my radio anyway.

 

Also, the capacitor is to reduce EMI that typically shows up as static on AM radio stations.

 

Since I don't use the radio I mounted the points cap on my coil. It makes changing them very easy, they don't last as long as the originals.

 

I didn't understand your post.

 

The only capacitor that you NEED is the one for your points. The rest reduce interference with AM radio, which you probably don't listen to anyway.

 

What destructor is saying is he moved the capacitor from under the cap in the distributor to the coil and connected it to the coil- terminal. Electrically its the same potential. He's also not running the noise suppression capacitor that was originally connected to the coil+ terminal.

 

He's saying he had a leftover capacitor from an old points setup, so he put that capacitor on his coil. And since it's the points capacitor, it's easy to find.

 

The Points capacitor was moved to the coil, since capacitors are now cheap junk I keep a spare with me. Changing them when mounted on the coil is quick and easy.

 

No, the points capacitor is still mounted to the points inside the distributor. The other capacitors in the engine bay are to reduce electrical emissions that affect AM radio.

 

Yes, the points capacitor can be moved to the coil if one doesn't need the mount at the coil for a radio suppression cap. I have been running my Cutlass for 10 years with the points cap mounted at the coil.

 

Apparently, they are different. For example in 1966, the part number for the one on the ignition coil was 1935729 and the one in the distributor was 1932004. The one on the voltage regulator was yet another part number: 1960957.

 

That could be due to the connector type not the size of the capacitor.