ignition coil ?

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flathead31coupe

flathead31coupe

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iam running duel points, and noticed that when my car idles for a while and the temp get to 200f it will start to run rough and dies but will restart, notice the fuel gauge showes 5# and the carb bowls are warm to the touch...but the coil is too hot to touch....its mounted on the pass fender in a vert position but is close to my coated headers... dont think ite should be that hot.
 
Some coils run hotter than others.
Over 140 is too hot to hang on to for long. Metal cased ones run hottest. Hi-po metal coils should be run studs facing down, so that the transformer runs in the oil.
However, the more voltage you pull thru them, the hotter they will run; this is why you always run a ballast resistor in series with the power supply.
Furthermore, with a point-trigger, you ought not leave the ignition in the "Run" position for extended time,with the engine NOT running because if one of the points is closed , then it will be sucking voltage thru the coil for no good reason, and possibly shortening the lifespans of both the points, the ballast and the coil.

This is why I like the Accell Big yellow square top coil, because it has a huge oil reservoir, and a non-metallic case. Mine was new in year 2000 and is still going strong. I mounted mine horizontally on the apron and studs down. It has taken everything I dish out to it, all the way to 7000 and beyond. If you get one, also get the matching ballast.
 
need to mount coil in a different place....but where.... if its futher away from the coil do i need a special coil wire or plug wire for the lenght
 
I bought a 3ft length of bulk metal-core secondary wire. It's part of my anti-theft system; I take it with me into the hotelroom when away from home.
My coil is on the horizontal part of the apron. I have seen guys mount it to the firewall, which is not far from the headers either.....
IDK how hot is too hot, but the oil inside should be good to perhaps 230*F or more. I think, until it starts leaking oil, it should be fine.
 
Last edited:
flathead31coupe said:
iam running duel points, and noticed that when my car idles for a while and the temp get to 200f it will start to run rough and dies but will restart, notice the fuel gauge showes 5# and the carb bowls are warm to the touch...but the coil is too hot to touch....its mounted on the pass fender in a vert position but is close to my coated headers... dont think ite should be that hot.
Click to expand...

You may have wrong coil or mis-matched ballast. At least one Accel coil and the old rectangular huge Mallory "box" coil both needed special ballasts IN SERIES with the factory ballasts
 
My guess is the fuel in the line from fp to carb has vaporized

My stock 273 2bbl does almost the same thing. When the engine is at operating temp and at idle, the fuel filter will empty, the line pressure will stay at about 5psi, then the engine will start to decrease in rpm right before the pressure in the fuel line starts to drop, then the fuel filter refills, the pressure comes backup, the rpm increases, and then the cycle starts over again
 
If you are running the car on 12V to the coil it will get hot. It should be running on 8 volts by using a ballast resister. Ign. 1 should be 12v to start. ign. 2 should be around 8V to run

The heat at the carb bowls can be decreased using a fuel return after the carb with a return regulator which is different then a pressure regulator. This keeps the fuel flowing and prevents the engine compartment heat from heating the fuel that is otherwise dead ended at the carb.

All newer carbureted mopars 85-88 used a return filter with 3 connections after the pump to do the same thing. But after the carb is much better.
 
When my 1964 Valiant cut off while driving it home after purchase, as a quickie fix I jumpered 12 V straight to coil+. It ran fine like that for about 5 miles, then started missing terribly above 45 mph. I pulled over and found the coil so hot I could smell its paint melting. I then got another jumper wire so I could route it thru the ballast resistor and no more problems. I found some gomer had monkey-wired the key switch, using many loose spade terminals, plus they stupidly wired straight off the ignition switch to run an electric radiator fan with no relay in-between.
 
Oldmanmopar said:
If you are running the car on 12V to the coil it will get hot. It should be running on 8 volts by using a ballast resister. Ign. 1 should be 12v to start. ign. 2 should be around 8V to run

The heat at the carb bowls can be decreased using a fuel return after the carb with a return regulator which is different then a pressure regulator. This keeps the fuel flowing and prevents the engine compartment heat from heating the fuel that is otherwise dead ended at the carb.

All newer carbureted mopars 85-88 used a return filter with 3 connections after the pump to do the same thing. But after the carb is much better.
Click to expand...
i have a super charger with two carters...do you have a pic or diagram of the return? i have a filter with a return port befor going into the regulator
 
before and after . I eliminated the regulator on the feed and ran the feed right to the carb. Then I ran the return to the regulator and back to the top of the gas tank There are two different regulators . A feed style and a return style. I had to remove the feed style and install the bypass/return style

Holley 12-881 Holley Carburetor Bypass Style Fuel Pressure Regulators | Summit Racing

Holley 12-803 Holley Fuel Pressure Regulators | Summit Racing

DSCF0171.JPG


Steve 107.JPG
 
AJ/FormS said:
Some coils run hotter than others.
Over 140 is too hot to hang on to for long. Metal cased ones run hottest. Hi-po metal coils should be run studs facing down, so that the transformer runs in the oil.
However, the more voltage you pull thru them, the hotter they will run; this is why you always run a ballast resistor in series with the power supply.
Furthermore, with a point-trigger, you ought not leave the ignition in the "Run" position for extended time,with the engine NOT running because if one of the points is closed , then it will be sucking voltage thru the coil for no good reason, and possibly shortening the lifespans of both the points, the ballast and the coil.

This is why I like the Accell Big yellow square top coil, because it has a huge oil reservoir, and a non-metallic case. Mine was new in year 2000 and is still going strong. I mounted mine horizontally on the apron and studs down. It has taken everything I dish out to it, all the way to 7000 and beyond. If you get one, also get the matching ballast.
Click to expand...

@AJ/FormS I keep a spare resistor in the glove box. Are these special 0.85 ohm ballast resistors necessarily and/or has your experience been with the same resistor too all this time? thanks in advance
 
My Square-top Accell Super coil has been running on the same resistor since I installed it, back in about IDK 2002?. No, I do not keep a spare resistor. On one of the spade terminals on the resistor, I installed a a connector with a twin spade on it. If my resistor ever burns out, I would simply move the wires together, and run the coil on full battery voltage, until I got home.
Accell says to run it on that resistor, and since my coil was new in 2002,and continues to function today, I'm inclined to think that running the specified resistor is the right thing to do.
The instructions say that coil is not recommended for over 6500, but mine goes 7200 and more with no hick-ups. And it idles all day as well.
Since I no longer run the factory-type ECU; I no longer run the dual-ballast. In an earlier post Del says that the P4120889 Accel Coil is supposed to run that factory ballast, in series with the Accell ballast. I did not know that, and my coil has only ever had the P5206436 ..... One-ohm resistor.
 
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