Farmall M electronic ignition

[GENETRY]

(quoted from post at 08:01:24 03/24/23) Hello

I am new to Farmall and tractors in general so I am learning.

Just purchased a 1946 M and it has a 12 volts and 6 volts. I would like to move to electronic ignition but the 6 volt ignition is throwing me off.

The tractor has a 12v battery, 1 wire alternator, starter, and lights, but it seems to have a 6 volt ignition system. There is a pull down resistor that takes around 12 volts in and brings it down to around 7 volts and then that runs directly to the coil. I called a tractor place to get parts and they needed to know if I have the stock setup or Delco ignition setup. I have been unable to find out which one I have.

I want to just go 12 volts all around.

 

[GENETRY]

(quoted from post at 08:01:24 03/24/23) Hello

I am new to Farmall and tractors in general so I am learning.

Just purchased a 1946 M and it has a 12 volts and 6 volts. I would like to move to electronic ignition but the 6 volt ignition is throwing me off.

The tractor has a 12v battery, 1 wire alternator, starter, and lights, but it seems to have a 6 volt ignition system. There is a pull down resistor that takes around 12 volts in and brings it down to around 7 volts and then that runs directly to the coil. I called a tractor place to get parts and they needed to know if I have the stock setup or Delco ignition setup. I have been unable to find out which one I have.

I want to just go 12 volts all around.

 

[300guy]

After looking at your last two pictures you have a resistor from what it looks like a Chrysler electronic ignition system. First take that off and throw it as far as you can!!!!!!
All you need is a single resistor to use on the 6 volt coil. Better yet take the coil off and put on a 12 volt coil. Then call Petronix help line and they will tell you by the coil what type of resistor and such to use with their system. Only real problem with the Petronix is DO NOT LEAVE the switch on or you will need a new system after a while.
I put a Petronix on my 300 in 1996 I believe and it works wonderfully. Every time I went to start it after it sat for a couple of weeks, I had to ALWAYS get my dollar bill out and clean the points. Since then it usually starts on or before the second go around.

 

[used red MN]

Those spark plugs have been run with a real rich
mixture. What is your process when starting the
tractor cold first start of the day? These Farmalls need
very little choke. Open the throttle up about a third of
the way. When you start it pull the choke out and roll
the engine over a couple turns. Most likely it will not
start on these turns. Stop push the choke all the way
in, while waiting 5 seconds or so. This wait will give the
gas that was pulled in the carb airway time to vaporize
a bit. Then crank the engine again, no choke. The
engine will likely start. During the warm up process the
engine should need no choke. You may need to hit it
with a quick out and in of the choke if the engine
falters during the first 15 seconds or so. If you are
going to move the tractor fairly soon after you start it
you may get ready to give the choke another quick out
and in when you let out the clutch and the governor
opens the throttle plate up. Do not run the engine with
half choke or something, if you do the result is the rich
mixture leaving the black residue you see on the plugs
in your photo. I have a way to clean those and they
would run as if they were good as new. Probably wise
for you to just get a new set. Now if when you tractor
is shut off and the carb CONTINUES to drip like every
5 seconds or nearly run a stream that would also be a
cause of the rich mixture and that problem in the carb
would need fixed. The fouled plugs will definitely make
it start harder.

 

[rustred]

Wow, I start my original 6 volt like this. Pull ignition button , pull choke out , crank it one revolution and it is running. And push the choke in at the same time. Then feather it a bit till it warms up.

 

[wh]

Thats how i start mine. Of course with the 12 volt set up it is running on 1/2 revolution 95 percent of the time.

 

[560Dennis]

Do you idle idle a lot ?

I cant plug numbers .

To cold a plug for idles.

Notice outside plugs are richer . Inside plugs 2-3 get warm up , what temperature is it running .

Electric ingnition isnt go to help your its just a switch. Waste of time and money with engine issues

Need to investigate the conditions of compression ,fuel , valve lash ,intake vacuum , blue spark should jump 3/4 of an inch .

 

[used red MN]

Rustred and wh maybe I should come over and video every start you guys make with your tractors to see if they actually start in a 1/2 or one turn. Well whatever. My main point and it it is MY opinion and experience that an H or M Farmall requires no ..feathered.. choking after it is running. As I said if it stumbles I give it a quick dose of choke. And usually after running 3 minutes or so no choke at all is needed unless it is below 20F than it takes a little longer to warm up. Anything more seems to foul the plugs from a rich mixture. The engine in my M was last overhauled in the 70s and it seen some real farm work and ground a lot of feed since then so it is far from a fresh engine, but still uses minimal oil.

 

[rustred]

guess i should have said, mine is 6 volt, as with all my 6 volt stuff everyone starts like that, from the w9 , w6 w4 one turn and running even after sitting all winter.

 

[Fritz Maurer]

I really dont see what is so strange about an M starting in 1/2 a turn. Its what they were designed to do. They had to be able to hand crank...M will wear you down quick if it takes a notion to not start... Im guessing back in the day the routine crankers of Farmall Ms paid close attention to the state of tune of their engines.

 

[rustred]

I can send u a video of each one starting on 6 volt. If I knew how to post a video I would put it on.

 

[rustred]

Yes u are right. With a crank its just one pull up and running. And with a mag also you dont need any cranking speed , slower the better. Even my w-14 on start up I Tryed to see how slow I could crank it to start , You would swear u could hardly even see the crank move and soon as the mag fired it was running. Even them old cats wed started with a bar stuck in the flywheel and turned like 1/2 a turn each time and they started. No other choice either.

 

[I550]

My Grandma had a couple of 6 volt
tractors, we used to park them on the barn
hill and roll start them. My Dad had a
oliver super 88 that was 6 volt. That one
wouldn't start either. We converted it to
12 volt and it was an easy starter.

 

[Fritz Maurer]

Ha yea I forgot about those, couldnt get much more than 1/4 turn on the old sixtys

 

[ss55]

Your system is the best of both worlds, stay with the 6 volt coil with the bypass resistor. That systems normally runs the coil on 6 volts, but temporarily supplies full battery voltage ( 10 to 12 volts ) to the coil during starting for the hottest spark available when the battery draw down is the worst case, especially in very cold temperatures.

Your alternator suggests that the tractor is now 12 volt negative ground. If you add an electronic ignition make sure to specify your voltage and polarity to avoid damaging the new electronic parts.