increasing current over time with electronic ignition

'50 sidemount N, 12 volts.
So a few weeks ago I got the Pertronix electronic ignition. Fired up first time once I figured out how to mount it, runs good.

HOWEVER, after mowing for about an hour, current started increasing, from an initial 1 amp or so, up to almost 10 amps. I noticed that and ceased mowing.

My theory was, coil resistance was decreasing as it heated up, and I wasn't sure if it was the recommended 3 ohm coil, so I got a new Pertronix "40,000 volts" 3 ohm coil, and am experiencing about the same. After about an hour, current had gone from initial 1 amp or so up to about 6 amps. When I put it away, I checked the coil, and it did feel fairly warm.

Did not have this behavior with the points.
One year old maintenance-free battery, any ideas ?
 
(quoted from post at 20:32:38 05/06/14) '50 sidemount N, 12 volts.
So a few weeks ago I got the Pertronix electronic ignition. Fired up first time once I figured out how to mount it, runs good.

HOWEVER, after mowing for about an hour, current started increasing, from an initial 1 amp or so, up to almost 10 amps. I noticed that and ceased mowing.

My theory was, coil resistance was decreasing as it heated up, and I wasn't sure if it was the recommended 3 ohm coil, so I got a new Pertronix "40,000 volts" 3 ohm coil, and am experiencing about the same. After about an hour, current had gone from initial 1 amp or so up to about 6 amps. When I put it away, I checked the coil, and it did feel fairly warm.

Did not have this behavior with the points.
One year old maintenance-free battery, any ideas ?
The 10:1 current increase does not meet the 'test of reason-ability'. I seriously doubt that such is happening. Find another way to measure & verify. Besides reason, the Pertronix unit would have failed & coil resistance INCREASES with increasing temperature.....by a lot!
 
where are you seeing this amperage reading?

the ammeter? if so.. you are seeing charge current tot he battery.. ignition draw is on the load side of the ammeter.. not the battery.. so ammeter will not show the draw of the ei module. it's all washed int he net charge/discharge.

only way to know what the ei draws would be to have a ammeter inline with it..
 
if coil resistance went UP when it heated up, then current would go DOWN, no ?

It COULD be EI un-related, except I'd done a bunch of mowing this year before switching from points to EI and didn't see this behavior.
 
also, my sense was, the way I have my ammeter wired, the only thing that indicates on the meter is what the ignition system is consuming. When it's running, what else consumes power ? (besides the headlights, which I have recently had off)
 
(quoted from post at 20:52:04 05/06/14) if coil resistance went UP when it heated up, then current would go DOWN, no ?

It COULD be EI un-related, except I'd done a bunch of mowing this year before switching from points to EI and didn't see this behavior.
esistance increase would result in current decrease.
 
Would this be a possibility ?

Does EI draw more current than points ?

If so, my alternator might not be up to the increased load ?
 
well.. HOW DO YOU have your ammeter wired?

I find it had to believe it is truly only inline with the ignition.

if your system is wired net like it was from the factory.. then all loads like lamsp and ignition are on one side of the meter.. and the battery ont he other.

that way, tractor not running and ignition or lamps on, the meter shows a negative deflection.

your meter normally is showing current charging the battery.. or discharging from the battery. other loads while running and a positive needle are being carried by the generator.. not running you have negative needle and the battery is discharging to power those loads.
 
I think....no offense, just stating an observation, that you have a fundamental misunderstanding of how electricity works with respect to the way your tractors charge system was designed.
You may or may not also have an electrical problem that could be an overcharge situation ( bad battery cell or bad vreg )

both remain to be seen.
 
with all due respect, I've been FCC (extra class) licensed for 50 years, I do understand electricity.
As I said, I'd done several hours mowing this year without seeing this (dis)charging behavior.

It COULD be co-incidental with the change to EI, but it does raise my suspicions.
 
(quoted from post at 21:15:24 05/06/14) Would this be a possibility ?

Does EI draw more current than points ?

If so, my alternator might not be up to the increased load ?
o, the resistance of the coil & if present, the ballast resistor set the current whether points or EI.
 
(quoted from post at 05:24:06 05/07/14) with all due respect, I've been FCC (extra class) licensed for 50 years, I do understand electricity.
As I said, I'd done several hours mowing this year without seeing this (dis)charging behavior.

It COULD be co-incidental with the change to EI, but it does raise my suspicions.

How do you figger to test yer spicions...
 
not ONLY inline with the ignition.
If I put the headlights on, adds about another 5 amps.

I believe I am monitoring what is going into/ out of the battery, so everything. But when it's been running for a few minutes, and charged back up from initial cranking, current draw should only be from ignition system, as long as I have the radio and the headlights off, what else is there ?
 
What is the charging voltage?

Does the battery show any signs of snotting out any acid though the vents/catching dirt there, etc?
 
Many of us here have HAM licenses..

Back to your issue.

A net wired ammeter is showing CHARGE to the BATTERY.

If your ammeter is reading high.. it's not because of the EI.. and you SHOULD know that with your 50ys of RF experience!

It is telling you more charge current is going to the battery!!!
 
I believe you are still 100% misunderstanding how your net charge / discharge system works.

draw it out so you can better see what is happening.

take a piece of paper. turn it on it's side, longways.

draw a 2" circle on the left, in the middle draw a 1" circle, and on the right, draw a 2" square.

now draw a line from circle one to circle 2, and draw a line fom circle 2 to square.

label circle 1, generator, label circle 2, ammeter, label square, battery.

now, on the left side of circle 2.. IE.. inbetween circle 1 and 2, draw a line down to a small 1/2" circle and label that lamps, scoot over a bit, but still between circle 1 and 2, and draw another line down and then a small 1/2" square and label that ignition.

here's how it should work... when running, generator making amps... amps are flowing towards battery, first stop is amps power ignition, then next stop is lamps, any leftover amps go toward the battery... crossing the ammeter makes it deflect positive, showing charge into the battery. Note the ammeter is not reading current used to power the ignition and the lamps, because those items were powered up the line before the ammeter.. thus current thru the ammeter is charge current only.

Now with tractor off, genny is not making any amps... so, with lamps or ignition on, only place to get amps is from battery.. thus amps flow from battery towards lamps and then ignition... your ammeter will deflect NEGATIVE showing discharge from the battery to both lamps and ignition.. in this state, the ammeter is reading the total load on the system as sourced by the battery.

that's why it is called a net charge / discharge system. net means leftover.. not gross. gross is the full output of the generator.. net is the full output of the generator, minus loads like lamps and ignition, result is net charge to the battery, OR discharge from the battery.

systems like this are wired with the battery, by itself on one side of the meter, and ALL other laods and charge devices on the other.

thus when running, with ign and lamps on, if you are seeing rising current.. you are seeing rising level of charge passing the ammeter to the battery.
 
just 'Murphy' messing with you...coincidence
putting the points back in with NO other changes and I bet the problem persists.
Charging system problem, or battery, or something as simple as a bad-dirty connection somewhere in the charging/battery circuit.
(hint, if you disconnected the battery properly when you put in the EI, I'd check that connection first)

points or EI, they are just a switch.
just like a simple toggle switch
which doesn't change your source power or the wattage of the bulb in the lamp/etc. It just allows/interrupts the current flow.
In fact, if you look at points closely, it is just a toggle switch,
with the dist cam being the little hand that switches it, very, very fast. EI use a magnet as the little hand, but same deal.
 
It occurred to me to use my (good quality) clamp-on ammeter at various places to see what's going on. I will report back if I find anything interesting.
 

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