Ign coil temp (how hot)

Looks like koates hit it on the head.

You need to add some resistance ( 1.5 ohms or a little less) . 1.5 coil winding and a 1.5 resistor (our RU11T resistor checks at 1.2-1.5 ohms) will give you approx 2.4-3 amps.

The other issue is by dividing the resistor into two 1.5 ohm unit the wattage ( heat) is divided . Thats the way it should be , should solve your heat issues.....

Als the lead wire from the coil to the distributor should be a finely stranded lead wire to drop the final voltage to protect the points......
 
A lot of these old systems are sensitive to excessive use of the ignition switch when the engine is not running or if someone forgets to turn off the ignition and it runs the battery down. If the points happen to be closed, the coil turns into an electromagnet and can get very hot. A lot of them bite the bullet from this type of incident.

The OEM coils on the 8BA Load-O-Matic ignition system had 1.05 to 1.15 Ohms primary resistance and a 4100 Ohm secondary resistance. With that and the OEM distributor wire that Bubba mentioned, the system would function as designed. Any changes to the system will have an effect that would likely be detrimental. If a person can't find a proper coil, a ballast resistor would be the only recourse.
 
I have ordered a new coil and condenser from Mac's for a 1951 8ba and would expect it to be the correct pair for my engine out of the box. Does this sound like a proper fix to you all. I'm hoping this corrects the miss (hesitation) I experience when under load at any cruising speed. Engine idles fine no miss, I have replaced dist cap and rotor, also set dwell at 27 degrees, adj carb and timing. I surely appreciate all the help, thank you-Bill
 
No personal experience, but there are a lot of reports of new condensers being bad from the get go.
 
X 2. The manufacturer's don't care if they work or not. They let the customer find out. I've pulled more than one pig tail out of those types without much force & found that they weren't even soldered. The materials might even be OK but manufacturing technique is off on some. At some point we may have to roll our own and stuff them in a home made can. A little trial and error with a capacitor tester and we might finally get some decent spark.

In the mean time, a person has to order 3 to get at least one half ways decent one. The IH 200 was good for a long time but manufacturing is going to change now that Standard owns Echlin. The high dollar Scintilla Vertex magneto capacitors might be the only good ones left.
 
At some point we may have to roll our own and stuff them in a home made can. A little trial and error with a capacitor tester and we might finally get some decent spark.

I like the idea discussed a while back with the "homemade" capacitor in a brass case. Any additional information on that?
 
billfish, Read again my post #20 and UNDERSTAND it. Regardless of which coil and which resistor you purchase and fit to your car, you have to do the amps current draw test with a TEST AMMETER and only then will you know the parts purchased are working correctly or not. Just guessing on components is not the way to do it. TEST, TEST, TEST and read the AMPS which should be 2.5 to 3 amps draw on the coil primary circuit and NO MORE. These suppliers will sell you anything and would not have a clue if they are going to work correctly. DO the TEST. Regards, Kevin.
 
Koates and Jseery- I'll get a test ammeter and check for amperage. I have a AW SPERRY DM-8300 DIGITAL MULTIMETER I use in my air conditioning work but not sure it will read amperage on the car circuit.
 
Koates--Jseery -when you say (in series with the coil battery supply)-exactly from where to where do I take this reading?
 
I like the idea discussed a while back with the "homemade" capacitor in a brass case. Any additional information on that?

I'm the one that described putting an IH-200 in the Ford condenser
shells. It's difficult and takes time. The best and easiest way is to
mount the IH-200 from Napa to the coil. Use one of the coil mounting
screws on the passenger to hold and ground the condenser. On the 39
type use a screw to hold the pigtail terminal to the brass tab on the
bottom of the coil. On the 36 type coil Put a screw though the hole
in the back of the coil where the condenser is held into the coil. Put on
a lock washer and nut and tighten good. Put the condenser lead terminal
on and another lock washer and nut and your condenser problems will
be over. G.M.
 
billfish, The test ammeter goes in series or inline in the coil primary. Remove the power wire from the ignition coil pos + terminal and connect one ammeter test lead to the removed wire and the other ammeter test lead to the coil + terminal that you removed the wire from. Do the test with the engine running at different speeds. If you do the test just with the ignition "ON" and engine not running the amps current draw will be higher than with the engine running. Engine running is the important test with no more then 3 amps draw. 2.5 amps would be great. Regards, Kevin.
 
billfish, I see your ford is still POS ground so connect your test ammeter into the ignition coil negative terminal which is the power supply wire from the ignition switch. Regards, Kevin.
 
Kevin-- With digital multimeter connected in series with neg ter on coil (wire from ing) and disconnected wire I get 1.9 amps at idle and the number goes down as I rev engine to belown 1.
 
Here's a picture of the meter I'm using and the connections and setting.
 

Attachments

  • IMG_0511.jpg
    IMG_0511.jpg
    58.8 KB · Views: 42
bill, That number seems a little low but if your ford is starting and running and pulling OK at speed then leave it. Did you just run the coil pictured without a resistor ? Regards Kevin.
 
I'd be interested to see what the current is through the coil with the engine off and the wire from the coil to the distributor disconnected and your meter connected from the coil to ground. Set the meter to DC current and touch the pos lead to ground with the ignition on. Just leave it on long enough to get a reading, then shut off the ignition.
Do you have the temperature probe for the meter? If so you could take the temp of the coil.
It would be a good idea to check the dwell of the distributor too.
 
As an electro magnet (engine off & Ign key on), they can pull around 5 amps with no added ballast. It just depends on the primary resistance. I would prefer a mechanical amp meter with a needle swing. The digital meter may have some built in shunting that may affect a series connected line reading.
 
Back
Top