Farmall M electronic ignition

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.

that is the stock ihc distributor. the delco is upright and uses a different rotor and points. i dont know what all else you have going on
there. all my tractors start just fine with original points and 6 volts, the same way they did when new. people change to 12 volt because
they dont know how to tune up a tractor. with points u will not be stranded as you will with electronic stuff.

i can also see the end of that rotor is burnt. is this tractor starting or not starting? i can also see the distributor is off. that wire terminal going to the points should sit right at the 3 oclock position when the timing is set correctly. and of course it can be due to someone not positioning the distributor correctly if they had it out. 12 volts on a 6 volt starter is also hard on the starter bendix slamming in hard. and there will be an up roar about that too. pretend your in 1950 and and tune it properly cause there was no 12 volt battery's then. the diesel models used 2 6 volt battery's in parallel for 12 volt.

The only thing that is 6 Volt or 12 Volt is the coil. The rest of the ignition system is actually tens of thousands of volts.

You have a stock IH battery ignition system with an original 6 Volt coil.

If you decide to put an electronic ignition on it you'll want to get one for 12V with the upgraded ignition coil. Just tell Pertronix that it's converted to 12V and they will make sure you get the right parts.

Regardless of what anyone says, leave it 12V. Sure you can make it work on 6V but it's constant maintenance. Something's always seems to be going wrong. One day it's slow to crank, the next day the generator isn't charging. It always seems to be something. You're always cleaning wire connections or fiddling with battery cables. None of that ever seems to happen on 12V. The tractor cranks over like it should every time without fail. The alternator just charges the battery like it should.

now i am laughing. and the tractor cranks over like it should. your too young to know how these old tractors cranked over and did the
farmers work. IHC made it work along with every other tractor manufacturer.

The electronic ignition is fine and dandy. The ignition module gets full voltage through a separate wire from the key to power it. the coil should be as described in the information supplied by Pertronics. It does not need to be a flame thrower hot coil for an M. Two issues that cause problems with them are leaving the key on when not running, and connections. They can fail, but it is not common. Keeping the original plate and points/condenser is easy to do. Jim

Well i am with Rust on stayen SOME WHAT STOCk . I don't have a problem with the 12 volt change as i myself have done them for years and left the 6 volt starter inplace the stock coil chande out the lights put the 12 volt battery in installed a resistor for the POINTS and Coil . as EVERYTHING that used Points has some sort of resistor installed on a 12 volt system . Some system will shoot 12 volt to the points on start up thru a by pass and once the started is out of the picture it goes back to 6-8 volts thru a resistor being it a mounted one or a resistor wire in the key side and wiring harness. Some over engineer there system with gobbs of wiring and fancyness . With and OLD proven set of Points like said they will never leave you stuck out in the back 40 where the NEW Electronics will and you are now dead in the water for DAYS while you WAIT for new pieces and parts , And one can keep on hand a couple sets of points for CHUMP CHANGE . One the OLD system that has worked longer then you have been around is simple easy to work on and nothing fancy is involved . Only tools needed is a 7/8th thin wall deep socket for the spark plug something else one should have on hand a feeler gauge with a .020 gauge or blade in it , a GOOD flat blade screw driver and a set of ing. wrenches and a small pair of pliers and a good timing light . As timing by ear is NOT the way to go on them as when doing so you will be way to far advanced tuning this way as and old M-450 engine should sound like it is laboring not running super smooth . Now depending on What is under the head for pistons and on this God only knows as i am dead sure it has been over hauled more then once in it's life time and each and everyone has had the newest part out there at that time installed as i have never meet a farmer who has not wanted more out of there tractor . So if by chance it was still stock then the ing timing may be still up there but more then likely the advanced timing for it has been cut back and you always set timing on Farmall and Internationals at what they called HIGH IDEAL aqnd that is WIDE OPEN THROTTEL and set for FULL advance . In my area we still have a ton of working M's on up doing what they have done since new and each and everyone i know of still run the OLD POINTS.

Have a super a and two hs. All on 12 v 3 wire alternator. Only reason they used 6 volt on these units is because that is what was available. Sure 6 volts works
but have to keep the system in perfect condition. A hand crank magneto works fine but not for me. 12 volt system even better. Battery cheaper, lights brighter,
can use 12 volt sprayer, easier to jump start or easier to use to jump start something else. Been running these for close to 40 years. Replace a bendix on starter
maybe once every 12 years. Just pull up on rod or mash button slowly to engage starter. No problems. If 6 volt power was so grand why does all modern
equipment use 12 volt. For those that want and like 6 volt go for it. Dont bother me one bit. My systems will be 12 volt.

Hello Genetry welcome to YT! I would like to know
where the 3 wires are connecting to that come off the
top of the resistor? It is more common for the resistor
to have only 2 terminals and be fed power from the
ignition switch on one end and the other end goes
straight to the coil. That resistor is from a Chrysler
automotive application and I believe it actually has two
resistors inside it of which each of their ends connects
to one of the spades on each corner. I am not sure
what the purpose of the two resistors was in the
automotive application but I believe only one side was
used to feed the coil. There is a test you could perform
with a quality ohm meter that could tell you if you have
the right resistance in your coil circuit in your current
configuration. We can come back to that later if need
be. The electronic ignition manufacturers will
recommend a certain coil configuration to pair with
their system. As far as the distributor terminal pointing
the wrong spot and to immediately say your timing is
off do not worry about that. No it is not the stock
location IH had it set from the factory but it will run
fine like it is. The internal gearing is likely off a tooth
and the distributor housing is just turned a different
amount of degrees to match it. Once you get it running
we can go through steps to set the timing correctly.
That point was made because some people like things
a certain way. And if it is not that way it would bother
them every time they saw it. They also have the
knowledge to correct it and reinstall it correctly
without a hitch. For you I believe it probably is a
complexity you really do not need to add at this point.
On another note do you plan on using the hydraulic
system? The oily knob thing with the screw in the top
is the reservoir cap. When using the hydraulics the
screw plugging the vent is not ideal. Step back a bit
and take a picture of the entire hydraulic system and
post it so we can see it.

I resisted changing my S/MTA over to 12 for years . Yea it started on 6 ok as long as you could find a GOOD 6 VOLT battery , They were hard to come by and when ya did get a group five you paid dear for it only to have it go bad in short order . So why not change to 12 when ya can fit a group 31 in the box or atleast a group 27 for half the cost and last two to three times longer , Then the advantage of some real HEAD LIGHTS and not two Bic lighters shinning the way at night . So i made the change but i made the mistake of changing the gen over to 12 volt , The gen is fine it is the junk regulator that are the problem now If you can get them to kick in and charge then they don't want to kick out when ya shut the tractor down . So once the weather breaks the gen is coming off and the alt. is going on. The other problem with the old 6 volt system was the lack of charge rate . It was fine for those who ran the tractor all day and went to the house when the sun went down , Not so good for the guy that worked and away job durning the day light hours came home by four then did evening milking then went to the field till 10:30 -11 at NIGHT Then parked the tractor . Next night she maybe a little hard to start but end up running fine for around and hour after the headlites came on then start with the missing or just flat up and DIE due to low battery . It was worse when they added in just one more rear light . I don't care what ya did the old 6 volt system on tractors could not put out enough . I remember my 1956 Ford , it was the first 12 volt in Fords with a gen. Yea with the 12 volt mine started great in winter where my one friend 55 that was 6 volt once it got down to the 20's he had to keep a heat lamp going under the hood so it MIGHT start , BUT when it got to 0 Nah it would not crank over . Even mine with the 12 volt when you had the lights on and heater going full blast when you pulled up to a stop she would discharge and the head lights would go dim and the heater fan slowed way down.

(quoted from post at 09:40:42 03/24/23) now i am laughing. and the tractor cranks over like it should. your too young to know how these old tractors cranked over and did the
farmers work. IHC made it work along with every other tractor manufacturer.

Click to expand...

Assuming you're talking to me due to the "cranks over like it should" remark.

I'm not too young to not have experienced the wonderful 6V electrical systems that IH put out from 1939 through 1956. Until we converted it to 12V the M would barely crank over. Dad went through several new batteries. He put new heavy battery cables on. Hell he doubled up on battery cables. He bought a new "hi torq" starter from Central Tractor and put it on. It would roll over half a revolution and stop. Hit it a few times, and it would roll over another half revolution and stop.

We tried all the tricks and tips that y'all tell everyone here. None of them worked. Put a 12V battery on it, and it cranks over LIKE IT SHOULD.

Had a similar experience with a W-400 he bought later on. Came 6V. Barely cranked over, half a rev, click click click, half a rev. New battery, same. New cables, same. New starter, same. 12V battery, boom, cranks LIKE IT SHOULD.

Yeah, I am not so dumb to think that only turning over 1/2 a revolution at a time is normal.

This post was edited by BarnyardEngineering on 03/24/2023 at 10:54 am.

Delco's I believe had a tag attached to
them with Delco stamped on the tag.

I read alot of problems on here regarding
electronic ignition or the confusion in
converting over. Moreso than I read about
problems with the distributors.

I dont think I'll be converting any of mine
over to electronic ignition. Distributors
are now old school. But yet they are
simple. Might do you more good to learn how
to maintain a distributor, than muck things
up with something else you don't
understand. Its easier to sort through the
confusion when there is problems, if what
you have is factory or equivelant. Easier
to make things as they were or suppose to
be, rather than dealing with add on
unknowns.

This issue can be thrown into the box of
(if it ain't broke, don't fix it). Your
tractor wasn't converted to 12 volt so you
can add on your electronic ignition. Your
tractor was converted over to 12v for other
reasons. And the distributor wasn't one of
those reasons. That's why it wasn't changed
out at the time of the conversion.

As to your confusion to the (why 6v
distributor), it was left as is during the
conversion. It's just fine with the 12 to 6
resister in its feed from key (or run/kill
switch).

In addition the 1st link will show a post from another forum that shows pictures of both types of distributors. The second link is to the manufacturers online parts catalog. I am going to place a copy and paste info about it so this may be why some of the items mentioned there may seem a little left fieldish.
..The diagrams there will give you a look at the parts that make up you tractor and where applicable will give you a look at what is inside. If it is not obvious many parts are no longer available. For a time IH simply removed part numbers they no longer sold for these old tractors so a lot of part numbers and descriptions are not there. You can click on a part number and see if the part is available. Sometimes if it shows unavailable a bit down on the left it says ..Replacements and Substitutions.. click the ..View more.. under it and then it may show you a current PN for the item that is available. Seeing the prices there may require you to select a nearby dealer. Also sometimes the prices are insane or laughable however you want to see it. For alternative sources a web search of the part number may be useful. That is also a good method to use for parts that are difficult to find. From this same page you can navigate to see all the different part sections for your tractor. If you lose the page just select ..Model.. in the Search at the top which is default and type in Your tractor model, like Farmall - - and Search and it will come up in the list to click to open. I would highly recommend using a PC to view that sight. At least I have found it to be fairly quirky on an iPhone. Hint, if you have a phone you need to hold it sideways to see the navigation arrows at the top.
Just FYI the Delco distributor is not shown in the M catalog because it was offered later a replacement accessory when owners wanted to replace their magneto.
If you want a free document to access to reference for repairs on your tractor send me an email and I will reply with the info. I do not like to post it here due to our hosts also sell manuals. When you are logged in the email buttons are at the bottom of my reply boxes.
I see the TV unleashed on you. He is very knowledgeable and experienced on IH stuff but his info requires some interpretation. Maybe he should keep a spelling cheat sheet by his computer of common tractor terms like ..idle.. and ..throttle..
Distributors

CNHI Farmall M online parts catalog

The only thing that is 6 volts on your tractor is the coil. That is why the resistor is there the coil can't take the 12 volts. I have a
M with electronic ignition and 3 others as well. There is always debate on whether or not electronic ignition is good or not. I would say
90% of failures are human error. Can they still fail? Sure,nothing is bullet proof. I'd say they are just as durable as the points and
condensers are these days. The modules are voltage sensitive so you need to do things right. You need to check if you have 3.5 to 4.0
ohms of resistance. No more, no less. Second you need to make sure your distributor bushings are in good shape. That goes for points too.
Third you will need to change your copper core plug wires to suppression plug wires. If the copper core wires are used it will develop
like a electromagnetic pulse that could damage the module. As far as leaving the keys on thats never good even with points. If they'd
happen to be closed they would burn up too HOWEVER supposedly the newest Petronix modules are safe from leaving the key on. My M has been
on the module since 2003 and no issues at all. My other 3 (Fords) tractors that have EI are going on 10 years since the change with no
issues except for one and I'll take full responsibility for that. Long Story. LOL. I have no problem with points,I just changed some of my
tractors over for the fun of it. If they give me issues and I want to scrap the EI idea I still can go right back to points its no big
deal.

Maybe that hi torque starter he bought was 12 volts. Just
maybe hey ? And your old 6 volt starter was actually the
problem. I have a Massey 44 that does the same thing.
While the other one spins fine. Its easy starter , cables ,
push start switch or pull start or battery, pick one. Not
getting into high compression just a factory unit.

(quoted from post at 09:19:08 03/24/23) i can also see the end of that rotor is burnt. is this tractor starting or not starting? i can also see the distributor is off. that wire terminal going to the points should sit right at the 3 oclock position when the timing is set correctly. and of course it can be due to someone not positioning the distributor correctly if they had it out. 12 volts on a 6 volt starter is also hard on the starter bendix slamming in hard. and there will be an up roar about that too. pretend your in 1950 and and tune it properly cause there was no 12 volt battery's then. the diesel models used 2 6 volt battery's in parallel for 12 volt.

Click to expand...

It is hard to start, but when it gets going its fine. New Fuel filter, but I have not checked the plugs yet.

(quoted from post at 10:32:50 03/24/23) Hello Genetry welcome to YT! I would like to know
where the 3 wires are connecting to that come off the
top of the resistor? It is more common for the resistor
to have only 2 terminals and be fed power from the
ignition switch on one end and the other end goes
straight to the coil. That resistor is from a Chrysler
automotive application and I believe it actually has two
resistors inside it of which each of their ends connects
to one of the spades on each corner. I am not sure
what the purpose of the two resistors was in the
automotive application but I believe only one side was
used to feed the coil. There is a test you could perform
with a quality ohm meter that could tell you if you have
the right resistance in your coil circuit in your current
configuration. We can come back to that later if need
be. The electronic ignition manufacturers will
recommend a certain coil configuration to pair with
their system. As far as the distributor terminal pointing
the wrong spot and to immediately say your timing is
off do not worry about that. No it is not the stock
location IH had it set from the factory but it will run
fine like it is. The internal gearing is likely off a tooth
and the distributor housing is just turned a different
amount of degrees to match it. Once you get it running
we can go through steps to set the timing correctly.
That point was made because some people like things
a certain way. And if it is not that way it would bother
them every time they saw it. They also have the
knowledge to correct it and reinstall it correctly
without a hitch. For you I believe it probably is a
complexity you really do not need to add at this point.
On another note do you plan on using the hydraulic
system? The oily knob thing with the screw in the top
is the reservoir cap. When using the hydraulics the
screw plugging the vent is not ideal. Step back a bit
and take a picture of the entire hydraulic system and
post it so we can see it.

Click to expand...

Thank you, I am planning to make a post on the hydraulics as well.

If you think a 12 volt battery is hard on the starter, your using the wrong bendix. 12 volt usually makes the starter last longer, less time cranking

(quoted from post at 12:33:55 03/24/23) Maybe that hi torque starter he bought was 12 volts. Just
maybe hey ? And your old 6 volt starter was actually the
problem. I have a Massey 44 that does the same thing.
While the other one spins fine. Its easy starter , cables ,
push start switch or pull start or battery, pick one. Not
getting into high compression just a factory unit.

Click to expand...

The starter is 12 Volts. I just had it freshly rebuilt. The Battery Positive goes from Battery to the foot switch, then to the positive on the starter. The negative is straght from the battery to one of the bolts on the starter. I cleaned everything up to make sure the ground is good. From there everything else is grounded to a bolt near the brake pedals. I replaced all the large wiring with 2/0 cable. Yes I know its overkill but I have about 200 feet of it from various other projects so I used it. The old worn out 0 wire that was there was causing other issues like bad ground and stalling out occasionally.

I really wanted to just get rid of the resistor, My other M does not have a resistor and its fully 12 Volts. The coil says internally resistive. I like as few of wires as possible.