Technical Ignition coil-does size matter?

1957 Chevy straight 6 230
Drive home tonight engine started sputtering a little when I accelerated.
Got home in the drive way noticed it was idling very rough.
Change fuel filter, checked plug wires.
Ignition coil, if I replace does size matter?
Rotor?
Check vacuum?
Not a mechanic, bought the truck so my kids and I could work on together and learn together. My point, I will probably ask stupid questions.

 

Chen the points, and maybe replace the condenser, before all that other stuff

 

I think I would check the ignition side, how do the plugs look? I would doubt it is the wires so the next place would be the points (assuming stock distributor), if the points have gotten too close together they may not be allowing the coil to saturate enough for a good spark.

My father in law told me he had did a tune up on his 57 Ford (in about 1959) and his wife said it would miss sometimes. Well he opened up the distributor and found that he hadn't tightened the capacitor down and the screw had rattled loose. he hated admitting that to me

In about 82 or 83 I was within about ten miles of home having just attended the Street Rod nationals in Oklahoma and the car started running ratty and then quit. The guy that had ridden down with me quickly diagnosed the problem as points (a dual point Accel POS distributor) a little bit of adjustment and we were on the road again.

Good luck, and there will be more (and smarter) people pass on some good diagnostic tips

 

So far as the coil goes, no, size doesn't matter. If it makes a strong spark, you're not going to do any better. I doubt that's your problem here, though.

 

Be aware that if you have to clean & adjust the contact surfaces of your points then the timing will change & that should be adjusted as well.

 

I once took apart one of those big yellow Accel coils because it wouldn't work, thought I just wanted to see what was inside. It bolted together, so it was easy to get into. The actual coil was small, in fact, about half the size of a normal coil! It slid up and down on a stud, and was bathed in oil. One of the wires had broken off, I reconnected it and had good free coil! Point is, I wonder how many guys bought one of those thinking it had a huge coil of wire in it, when it was actually less in size than a standard round coil!

Like was stated above, it's doubtful the coil is your problem. More than likely the points need cleaning and adjusting and the condenser could be going bad. Lots of talk on how the new condensers don't last like the old ones did.

 

Well. I say it's a fuel pump. Maybe it's just to be different, or maybe, it's because he mentioned he wasn't a mechanic and I heard what he said and thought, he could be right.

Admittedly, I could be wrong to. Anyone giving odds.

 

Replace the condenser. If its old its worth doing anyway. A faulty one can give the symptoms you are seeing.

 

Thank you

 

Thank you

 

Check simple things-points clean and gap correct, fuel-dirt/varnish in carburetor-clean passages with carb cleaner, vacuum-broken or loose lines.

 

Have you opened a standard round coil? I'm guessing the contents of those aren't all that big either.

 

I wouldn't get "into" fancy brand names, I'd rather find old NOS replacement parts from reliable old line companies....

the last new set of points I installed was NOS Delco that came in the foil covered box. Remember those? Usually I just clean the old points and add a tiny dab of grease to the rubbing block, they tend to work better/last longer than new replacements.

 

Yeah, pretty much all new ignition parts come from the Shanghai speed shop now. I've got a pile of N.O.S. 40 to 50 year old point sets and condensers that I picked up for little or nothing at various swap meets.

 

Sure have. The inside was wound from about 1/2” of the bottom to the same at the top. Don’t remember what brand it was, too long ago.

 

Shop ebay for AC Delco D108P points and D203 condenser. Look for NOS still in the foil packages.

 

Whenever somebody is just getting started diagnosing a problem like this for the first time, and the problem may in fact be ignition related, I feel morally obligated to suggest they read this copy of Basic Ignition Systems from the HOT ROD Magazine Technical Library series. You don't need to memorize every last detail. But it could save you a bunch of time, frustration and money as opposed to just throwing parts at what you might think is the problem.


https://www.jalopyjournal.com/forum/threads/hot-rod-technical-library-basic-ignition-systems.983424/


You might also post where you're located. There may be a HAMB member who lives in your area that might be willing to lend a hand.

 

I don’t recall a foil wrapped set of points. NAPA had Exhlin, they were in a small cardboard box you’d open at one end and let them slide out.

 

Diagnosing (and solving) distributor problems - Hagerty Media

- If the spark is weak, the engine is rough under load (working hard) or higher revs, or the points are badly burned, or the condenser could be failing. It’s worth replacing this as a matter of course or at least having a new one as a spare.

I think in our urgency to solve the problem, we rush in and fail to learn together.


If someone doesn't raise the question of doubt, what do we learn besides if you say so I'm following you off the cliff. Drinking the Kool aid. Taking that shot in the arm. Handing over my gun.

Buddy just walked into the shop, said to the counter man, "it's acting up".
Counterman says, this is the problem, this is what you need. I don't need to look cause I know.

Classic doctor playing God. I'm the second opinion. The let's not jump to conclusions, let's do a few more tests to confirm.

A visual inspection of the points, that counts. But if you don't know what you're looking at, that makes it harder.

• Difficult Starts. ...
• Sputtering Engine. ...
• The Actual Stall. ...
• Power Loss. ...
• Surging Power. ...
• Lower Fuel Efficiency. ...
• Dead Engine.

Signs of a failing fuel pump. But it could also be other things, I'll give ya that. You could check that fuel pump quite easily with a 2liter bottle and a rubber hose cranking the engine over. A possible learning moment. Kid cranks you hold the bottle, then switch.

Fuel System Tech (devestechnet.com)

And the thing about coils, not that I know much about them, but isn't wire size and wraps that figure into the spark voltage equation somehow? Input/output, it's confusing. Who measures that anyways unless there's a problem. Even then.

Let us know Pat. Because while emery paper or a points file will dress things up, the dab of dielectric grease will lube the foot, testing the condenser I openly admit can be easily checked, it might still be the fuel pump.

nonlintec.com/sprite/cap_failure/

-I mounted a distributor in my lathe, so I could spin it, and connected it to a coil and spark plug.

Yea, why didn't I think of that, probably because I don't have a lathe.

 

6 or 12 volt----no difference.

 

Give that cam deal that the rubbing block of the points rides on a visual. It should look more like a hex nut than a round bushing. It's not real common but that can wear down and not provide enough gap in the points.

(I hope I didn't confuse anybody by using such technical jargon. )
..

 

I always thought if the lobes wore, points could still be adjusted to compensate. I guess if it went round, then no dice. Never put much thought into it through.

 

You probably know more about points than I do. I'm no expert. I've only changed or adjusted points in a few of my own vehicles. If the tab on the points wears I'm sure there's plenty of adjustment to be had for the right lift or gap. But if the cam deal wears I'm thinking that the amount of gap and maybe the dwell can get wonky. (?)

 

Thank you
Located in Kingwood, Tx just outside Houston

 

Found a copy on Amazon, ordered!

 

Was gas added shortly before the misfiring? Exhaust get plugged , backfire with a vacuum hose that popped off , did you get on it and possibly pick up a piece of trash from the gas tank and block some passages in the carb ? If no to the above then check the points as others have suggested.

 

"Does size matter?" I sure hope not, or we'd all be running them big, ugly, yellow things.

 

Oh, no. I was just asking. I’d see that dwell will change, just always assume it could be adjusted with the points.

 

It also helps to remember that the ignition points adjustment and ignition timing adjustment share a somewhat unusual relationship. Changes in the points dwell adjustment will also affect the ignition timing. But changing only the ignition timing has no affect on the dwell adjustment. Kind of a "Catch 22" situation, but not exactly. It just takes a little time to wrap your brain around why it works that way, but it does.