Ever Have an Ignition Condenser Fail?

[SacramentoJoe]

I was driving, just shifted into 3rd gear and, out of know where, my truck bucked a couple times and started stumbling. It felt like a fuel pump failure. I pulled over and checked the carb. The in-carb filter had some debris in it, but there was pressure when I cracked the line. Accelerator pump was squirting too. I tried to limp it a couple miles back home but sputtered so bad I could not keep it moving. I pulled a plug and checked the spark, which was sparking. So now I have fuel and spark. I couldn't even get it to run anymore.

I'm thinking, what the heck?

[Steeveedee]

Did you replace the condenser and get it started? I'd pop the distributor cap and make sure that the rotor points to #1 plug wire when the engine is at TDC, you know that you have fuel and spark. Sounds more like it jumped time.

I've only seen 2 or 3 failed condensers in all my years of mechanic work.

[54blackhornet]

Distributor appears to be pointing in the proper orientation. Points are worn and not opening enough ? I have a 307 myself. Engine ran terrible with points, I ended up installing a gm HEI and all the issues disappeared.

[RustyPile]

OK, so you have good fuel pressure and fuel in the carburetor.. Also, you have good spark at the plugs.. so what's left could be, as mentioned, timing chain failure. If your engine has high mileage, this is a great possibility. Easy to check this..

Remove the distributor cap so you have clear view of the ignition rotor.. Using a socket and long handle breaker bar or ratchet, slowly rotate the crankshaft while watching the rotor. When it starts to rotate, STOP turning the crankshaft.. Using nail polish, paint, chalk, or other marking device, put a reference mark on the harmonic balancer and timing tab. Slowly rotate the crankshaft the other direction until the rotor again just starts to move then stop.. This measures the amount of slack in the timing chain.. Four degrees is about 3/8" movement at the balancer. Any more than this is too much, often times, enough for the chain to jump a tooth or 2 at the gear, throwing the timing off and the engine will no longer run.

[SacramentoJoe]

When it would start running, I'd pump the gas pedal and it would suck air through carb and "brap, brap, brap" it would die. It really sounded like it wasn't getting gas. Since the filter was full of crap, I pulled the carb off and checked the needle, float, jets, and venturis were all clear. Other than sediment in the bowl, everything looks okay. I did notice that fuel was leaking from the throttle rod seal. Put everything back on the engine and still not running.

Back to look at the spark again. Points and condenser look new and they only have about 1000 miles on them. Pulled a plug, and although there was spark, it didn't look super bright blue. Checked the coil ohms, which were out of spec so I threw a new coil on it, but that didn't help.

Hmmm? At this point I am thinking maybe it jumped timing, but I replaced the chain just last year.

Pulled the points again, and removed the condenser. Tried to find how to test it. Found a lot of British Youtube videos.

[Rust_never_sleeps]

This one's pretty concise. Anecdotally, the British shows I used to watch indicated that when points went bad, the condenser was always still good, or maybe that's just what they believed

https://www.forabodiesonly.com/mopar...-ignition.186/

[1970cstblazer]

I would be removing those points and condenser, and replacing with NOS Delco Remy parts. I buy mine on EBAY. The current offshore replacements are pure trash, and will eventually leave you stranded, especially when heat and moisture and in the equation. The coil should be looked at too. Points distributor get a bad rep due to junk parts. When set up properly, I find them more reliable than most electronic systems, especially in hobby vehicles.

Cap: D308R/ 12338667 OR 1971244
Rotor: D409/1932015
The light duty rotor D426R 1852722 is an option, but I never liked them
Points: D106P/1931988
Condenser: D204/1932004
Uniset points/condenser: D1007 1876600
Coil: D512/1115238

[truckster]

Even if the condenser failed it wouldn't cause that problem. You could even run your distributor without a condenser... for a while. The condenser's only function is to absorb the excess energy when the points open in order to reduce arcing. If the condenser fails, the points burn up pretty quickly.

[Tomchev]

Yes had them go bad. Sometimes would run fine next time leave you on side of road. Friend that worked at Chevy dealer said he's had them bad out of box.

[Palf70Step]

Originally Posted by Tomchev

Yes had them go bad. Sometimes would run fine next time leave you on side of road. Friend that worked at Chevy dealer said he's had them bad out of box.

Same here. Have had old and brand new fail. Not super common. But it does happen. As mentioned i went hei and the issues were gone.

[SacramentoJoe]

It was the condenser. I have never had one just fail catastrophically like that. I always use Blue Streak, but the new Blue Streak was different than the old one, so maybe it was a crappy brand. While I was waiting for the new condenser, I had plenty of time to review the YouTube videos. The bad condenser would not discharge like it should. I would ground it out, leave it for a while, and it would still show some residual voltage. I really can't explain why would cause my problem since I was still getting spark at the plugs, but that was the only thing that was wrong. Its running great now. Still leaking a little gas though.

[truckster]

Originally Posted by SacramentoJoe

It was the condenser. I have never had one just fail catastrophically like that. I always use Blue Streak, but the new Blue Streak was different than the old one, so maybe it was a crappy brand. While I was waiting for the new condenser, I had plenty of time to review the YouTube videos. The bad condenser would not discharge like it should. I would ground it out, leave it for a while, and it would still show some residual voltage. I really can't explain why would cause my problem since I was still getting spark at the plugs, but that was the only thing that was wrong. Its running great now. Still leaking a little gas though.

Interesting. I've not seen that happen in almost 50 years of working on vehicles, but I guess I'd better never say never...

I'm glad you got it figured out.

[1970cstblazer]

I have seen a similar failure before. Hence why I trust my stuff to 40-plus year old quality OEM sourced parts rather than the junk the local corner parts store has to offer.

['68OrangeSunshine]

Funny. you nailed it in the title. I usually changed out both Condenser and Points when I tuned up. Delco Remy and AC plugs, until they went south of the border.
Then Standard Blue Streak was my brand of choice.
I liked tuning with points [etc.]. It was easy, and you could keep spare points and condensers in your glovebox. If stranded in the desert, you could still change them out with a screwdriver and matchbook cover [for the Gap].
I tried Pertronix. It failed after about 7 years. I went back to points for a year, then went to HEI, once I found a distributor for the L6.
My V8s, I went for HEI in the '90s.
It is a performance enhancement.
Once, my '71 Jimmy stalled at night, coming home. I made the corner on momentum. I called Roadside Rescue. I decided to try my spare Module in the glovebox.
Sitting on my driverside fender, leaning over with a minimag in my teeth, I pulled off the Cap and Coil, unscrewed the old module, put the white stuff on the bottom of the spare module -- put it all back together, and it started right up. I had to call back to cancel my Hook truck.

Now that Matchbooks are very hard to come by, I'm not sure what I'd use if stranded. Maybe a feeler gauge?

[BROWN 70]

yes I have. BROWN 70

[SacramentoJoe]

It seems so simple in hindsight. I've had a lot of things go wrong over the years, but never like this. I've always seemed to find a way to figure something out and limp it home, like no clutch, or stuck in first gear, or fuel pump failure. From running fine to not running at all within a couple blocks, I thought I would've found something more obvious.

[Rust_never_sleeps]

I was under the same impression that the condenser just "cleaned up" the spark so the points lasted longer.
I found this demonstration illuminating:
https://www.youtube.com/watch?app=desktop&v=MQtMtvf5a4E

[SacramentoJoe]

Originally Posted by Rust_never_sleeps

I was under the same impression that the condenser just "cleaned up" the spark so the points lasted longer.
I found this demonstration illuminating:
https://www.youtube.com/watch?app=desktop&v=MQtMtvf5a4E

That was a very applicable video. YouTube knows everything.