8N hard starting finally resolved!

[NormS]

A year or more ago I posted a message about my 8N and the fact that it started hard, and the colder, the harder. Also, it
absolutely would not start unless the throttle was at minimum. Even then it was touchy. Well three weeks ago when it was -10
here I had the absolute necessity of getting it started to move it out of the pole barn. I cranked on it for half an hour,
choking, not choking, a little throttle, no throttle. It spit and spat now and then giving me encouragement that it just may go.
Well, no such luck and the battery by then was getting low so I put the charger on it and vowed it would start tomorrow. I
thought a lot about the problem and it came to mind that my dad had a similar problem with an engine on his International
combine when I was a kid. He eventually solved his problem by gapping the plugs at 0.010 (it was a magneto). Turned the crank
once and it took right off. So I thought, if it worked for dad, maybe it will work for me so the next day I took the plugs out
and re-gapped them to 0.010 and tried to start it. It showed more signs of encouragement so I kept it up and it did eventually
start. I moved it into my shop where it could warm up and I could delve into this problem and solve it once and for all. After
looking it over I decided to get a new cap, rotor, plug wires and a coil. The points and condensor were new two years ago. Just
to note, when I went through the engine two years ago I changed it over to 12V but kept the original coil and added a ballast
resistor. So I got the new ignition parts but before I did anything I decided to check one last thing. Got my voltmeter and
turned the key on. Battery voltage read 13.3 on the ballast resistor. The other side of the resistor connected to the coil -
which should ready about 6 volts, read not 6 but 2.3 - yes, 2.3! Well golly gee, no wonder it had a starting problem. Spinning
the starter probably dropped battery voltage to 12 or a little under and the voltage going to the coil was maybe 2.0. Seeing as
how I had the parts and the ones on the tractor were old, I decided to replace them anyway, including the coil, the replacement
being a 12V coil, no ballast resistor required. Changed all the parts, turned the key and pressed the button. Started
immediately. Today I went out to the shop, which was about 50, advanced the throttle to about half, pulled the choke and pushed
the button, WHAM, started right up!! Holy cow, it won't be a question mark any more when I go to start it, especially in cold
weather. Just thought I'd pass along this little story for what it's worth. It sure makes me feel sheepish that I just assumed
the ballast resistor that I put in was just fine without even throwing the voltmeter on and checking things out.

 

[wore out]

"I just assumed the ballast resistor that I put in was just fine:

Sadly, that approach does not work today with the "out of spec" JUNK that is sold even by "trusted" parts suppliers.

 

[showcrop]

Congratulations! When it is cold it needs a richher fuel air mixture. An open throttle admits more air, reducing the effect of the choke.

 

[charles Leddy]

I am not a fan of Ballast Resister and don't quite get why they are required? (I have read why) Some other brands of tractor have a terminal on the starter and give it full Voltage when starting and then go through the resister when running which probably eases the stress on the points and coil. Some old dependable tractors have been using hot 12 volt batteries on basically 6 volt systems and they keep going forever?

Ford has that square coil and I suspose do everything possible to protect it but round coils seem to be pretty forgiving?? At least it keeps the "Ford People" busy.Cleddy

 

[NormS]

A ballast resistor was used on hundreds and thousands of vehicles in the 50s/60s and some into the 70s. The reason was what you mentioned - spark boost when starting the engine by way of the wire from the starter side of the starter solenoid to the coil to provide 12V to the coil instead of 6V giving a much hotter spark when starting and battery voltage dips low because of the load. Even the 8N used a ballast resistor on at least the front mounted distributor models although there was no "boost" wire to the starter (and I'm not sure why they did that instead of using a coil that was designed for the full 6V). Using a 6V system on 12V may or may not affect the coil but when you consider that it is putting out twice the designed voltage, it may eventually fail prematurely if the insulation breaks down. More likely than not, the points and condensor will fail because of the double voltage and current. I've seen that happen myself. Back in the 70s some bright person came out with 8V batteries to use in place of 6V to give more starting power. Don't worry they said, just adjust your voltage regulator. Well, dad put one on his Cockshutt and it didn't take that long before the points failed. They even sold very large resistors to use to drop the voltage to the ignition and lights, and we had them, but the points still failed, the contacts burned to a crisp. So, yes, it is important that the ignition system run on the right voltage - both too low and too high do bad things!

 

[JMOR]

(quoted from post at 22:23:32 03/12/21)
"I just assumed the ballast resistor that I put in was just fine:

Sadly, that approach does not work today with the "out of spec" JUNK that is sold even by "trusted" parts suppliers.

or sure! Over the decade + that I have been watching/participating, it has been noted that the popular 8NE10306 resistor, sold by many outlets, vary in resistance value by 3 to 1!!! and i price by 10 to 1. $0.99or $9.99,.....still junk!

 

[1 Acre Warrior]

(quoted from post at 10:42:33 03/13/21) ]For sure! Over the decade + that I have been watching/participating, it has been noted that the popular 8NE10306 resistor, sold by many outlets, vary in resistance value by 3 to 1!!! and i price by 10 to 1. $0.99or $9.99,.....still junk!

There is a tolerance rating for each resistor. The most common, used in a few hundred billion devices over the past century, have a 10 PERCENT tolerance. The ballast resistors are good at a 30 percent or even 40 percent tolerance, because they are feeding a circuit that doesn't much care.

If you test one resistor that is at the low end of the tolerance, then test one at the high end, you might think that one of the two has failed, but not so.

 

[JMOR]

(quoted from post at 00:05:15 03/25/21)

(quoted from post at 10:42:33 03/13/21) ]For sure! Over the decade + that I have been watching/participating, it has been noted that the popular 8NE10306 resistor, sold by many outlets, vary in resistance value by 3 to 1!!! and i price by 10 to 1. $0.99or $9.99,.....still junk!

There is a tolerance rating for each resistor. The most common, used in a few hundred billion devices over the past century, have a 10 PERCENT tolerance. The ballast resistors are good at a 30 percent or even 40 percent tolerance, because they are feeding a circuit that doesn't much care.

If you test one resistor that is at the low end of the tolerance, then test one at the high end, you might think that one of the two has failed, but not so.

am fully aware of manufacturing tolerances, but in 30 years of electronics engineering experience, I have never seen a specified tolerance of +/- 300%. More like selling junk where these resistors are concerned!

 

[TheOldHokie]

(quoted from post at 10:17:56 03/25/21)

(quoted from post at 00:05:15 03/25/21)

(quoted from post at 10:42:33 03/13/21) ]For sure! Over the decade + that I have been watching/participating, it has been noted that the popular 8NE10306 resistor, sold by many outlets, vary in resistance value by 3 to 1!!! and i price by 10 to 1. $0.99or $9.99,.....still junk!

There is a tolerance rating for each resistor. The most common, used in a few hundred billion devices over the past century, have a 10 PERCENT tolerance. The ballast resistors are good at a 30 percent or even 40 percent tolerance, because they are feeding a circuit that doesn't much care.

If you test one resistor that is at the low end of the tolerance, then test one at the high end, you might think that one of the two has failed, but not so.

am fully aware of manufacturing tolerances, but in 30 years of electronics engineering experience, I have never seen a specified tolerance of +/- 300%. More like selling junk where these resistors are concerned!

Or perhaps stamping that part number on whatever white brick you can readily acquire.....

TOH