225 popping out the exhaust, but...

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FURY440

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The other day,.well for the last few times out with the car the engine just dies and or sputters while driving and pops out the exhaust and I mean loud. Even when I start it cold this happens sometimes. Then I'll crank it and crank it and pow out the exhaust. It's like the fuel is still getting to the cylinders and then the ignition just turns on again. I'm thinking ignition issue? It's got points still.
 
The symptoms described are exactly those of the ignition cutting out and back in. Trace the wiring to the ignition system from the key switch. It could be the key switch, the bulkhead connector, or any wire feeding to the ballast and over to the distributor. If could also be the condensor or coil, or even the points gap closed up from the rubbing block being worn down.
 
Ok,.checked the point gap and it's at .20. Timing is fine also. I did notice that the coil gets very hot and I mean hot where you can't touch it and also the ballast gets very hot also. This happens when the engine gets to operating temp. It just dies and I can crank it and crank it and get nothing. Once in a while it will fire back up and run, then stall again. Runs great when cold. Voltage is reading normal at the ballast. I'm thinking possible coil?? Any thoughts or test I can perform to narrow it down?
 
Yes it does sound like the coil. The points gap at .020" should keep the dwell from being too high, which could overheat the coil.

You can check the coils primary resistance between + and - terminals; stock will be around 1.5 ohms. Make sure you cross the meter leads together first and take a reading of the lead resistance alone, and then subtract that from the reading of the coil.

But, that primary resistance could be good and internal breakdown of the coil could still heat it up. So the sure way is to replace it. A lot of the box parts stores carry the Pertronix Flamethrower 40011 coil in stock for around $40-45. It is a 1.5 ohm coil which is correct for the stock Mopar system. And it'll pretty much give you as hot a spark as you can get from a canister coil of that size.
 
Thank you. Yes I found one at Advance Auto, so I'll give that a shot. Before I do that, when testing the coil, would I need to remove the wiring from it or can I run the test while it's hooked up key off?
 
My buddy had an MSD coil and gave it to me. Put it in and same thing happened, so I switched out the condenser and points he gave me also (NOS Mopar) and now it's fine. Even runs smoother and has better response. Thanks for all the help!!!
 
Yes it it is. It's really like night and day how it starts now. I can hit the key quick and it fires right up. Can't believe that a condenser would cause all that. Well looking on the bright side,..I gained a better coil out of it and better running engine. At some point I'm going to relocate the coil. It's bolted to the engine block in the stock location and I'm sure that has a lot to do with it getting hot. Also going to go with the PerTronixs ignition at some point.
 
Sorry I'm late to see this, that's EXACTLY what a bad condenser will do, not sure why....but it seems to store & not release a charge when hot. Then discharges and starts
to function again after a handful of seconds, I limped home in My '71 Olds 30 yrs. ago at 1:30 AM with a fresh leak in the crossover pipe,....suddenly I'm coasting then
KA-POWW!!!, then it ran for a little stretch.......LOL I'm sure the neighborhoods loved Me!
 
The condenser prevents (absorbs) arcing of the points. When the points arc, they act like they are closed, and a closed point is not firing the coil. do that 4-5 times in a row and then get a good one off and itll ignite its cylinder as well as anything left in the manifold.

We had a USMC guard mount gas truck do that, you get off the gas and about 3 seconds later it sounds like an 81mm mortar firing. The truck had about 4 feet of exhaust on it and I bet there was jack left in the muffler. Funny as hell because the duty driver would pop that thing on purpose a minute down the road before he pulled up on your post.
 
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Yeah,.I can't believe that a condenser would make it run terrible like that or not run at all. Funny thing is,.the points and condenser were fairly new. All is good now. I just need to rebuild the carb. It needs an accelerator pump bad.
 
New parts does not equal good for these old oddball parts any more. I still have the old condenser and points in my '62.... the condenser could be the original at 62 k miles.
 
I looked up the capacitance of an auto condensor << wrong application, way out of auto spec>>
 
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FWIW..... The capacitance spec for '62 /6 condensers is .25-.285 uF. (From an old Sun shop tune-up sheet.) I bet that did not change for years and years. I don't know the voltage but 600V may be adequate; I've measured a few hundred volts peak at the condenser with an o'scope.

I suspect the metal case is important for heat sinking.
 
FWIW..... The capacitance spec for '62 /6 condensers is .25-.285 uF.

Confirmed...I just measured one from a clean 69 points...281uF. I was using a microcontroller component tester and a capacitance meter.
 
Cool!

I mentioned the metal case and heat sinking as I would expect that this capacitor will probably get some heat in it. A low loss (low internal resistance) type would be needed since there is some current being pushed around here so some heat will end up in the capacitor even with and low ESR type. I would expect for the 40's-50's era, a paper dielectric type would be used; I am not sure mylar dielectric types existed in the 50's; they did in the 60's.

It would be tempting to get a high quality modern capacitor of the right capacitance value to get around the newer variable quality stuff, but I have to wonder how it would handle the heat.
 
Is this from your computer driven device? I just wonder how accurate it would be on such a parameter; 0.47 ohm is a LOT. Low ESR caps typically are in the 1 to 10 milliohm range.

Dang.... I just sold a GenRad 1611B that would have been perfect for measuring dissipation factor on these caps. Oh well, it was taking up space....
 
Yes it does sound like the coil. The points gap at .020" should keep the dwell from being too high, which could overheat the coil.

You can check the coils primary resistance between + and - terminals; stock will be around 1.5 ohms. Make sure you cross the meter leads together first and take a reading of the lead resistance alone, and then subtract that from the reading of the coil.

But, that primary resistance could be good and internal breakdown of the coil could still heat it up. So the sure way is to replace it. A lot of the box parts stores carry the Pertronix Flamethrower 40011 coil in stock for around $40-45. It is a 1.5 ohm coil which is correct for the stock Mopar system. And it'll pretty much give you as hot a spark as you can get from a canister coil of that size.



I know this is an old thread , but I have a dumb question.. I just switched out my coil ( 1965 225 / 6 ) with a 1.5 ohm flame thrower , do I need to use the capacitor that was wired to the old coil ? should I also swap that out ?
 
If it's wired to one of the coil terminals, then no you don't have to replace it..... that item if missing does not affect the running of your engine.
What it's for is for noise suppression on your radio, and more specifically for noise suppression on the radio of the car parked next to you,lol.
The alternator has one inside it as well for the same reason.
 
The other day,.well for the last few times out with the car the engine just dies and or sputters while driving and pops out the exhaust and I mean loud. Even when I start it cold this happens sometimes. Then I'll crank it and crank it and pow out the exhaust. It's like the fuel is still getting to the cylinders and then the ignition just turns on again. I'm thinking ignition issue? It's got points still.
If it doesn't do it when cold, then I suggest a hot compression test, maybe it's time for a valve adjustment, and then a fresh compression test.

Oh wait, I reread your post and it says also cold.

A cracked plug insulator can do a similar thing, until it fails to spark at all.
 
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