Farmall 200 ignition problem

[oregonfarmer]

My Farmall 200 has a problem. I was driving it when it kind of sputtered a
few times and then stopped, and it will not start again. I checked the
timing and wires, etc. I had a new distributor and installed it and that
did not solve the problem so I checked the coil and I have 6.2 volts going
in and the coil reads 3.9 ohms from terminal to terminal. Everything
appears to be all right but I still have no spark. This is a positive
ground and I have one wire from the battery to the positive (+) side of the
coil and the negative (-) wire goes to the distributor. I'm not sure what
is wrong.

 

[rustred]

your coil wires are backwards.

 

[used red MN]

Although it is not keeping it from starting the way I understand it you have the coil polarity incorrect. You say you have a wire from the battery to the coil, which I assume you have a wire from the ignition switch to the coil. Which yes the wire through the switch makes connection back to the negative battery cable. The wire from the ignition switch should connect to the negative (-) terminal of the coil. The wire from the distributor should go to the positive (+) terminal of the coil. You have a test meter so open the distributor cap and turn the engine until the points close and turn the switch on. With your red meter lead on a good chassis ground and the black on the distributor terminal you should get no voltage. Then turn the engine to open the points, battery voltage should now show on the meter. I am guessing the points are not making a proper contact to ground out the coil. Sand wipe and clean them until you get them to zero the meter.
.1 or .2 volts is okay. More then that the points are not working or contacting correctly.
Beyond that you may have messed up the timing some how.

Edit: Thought of this after my first reply. Every bit of this post is about the ignition. I hope you at least looked in the gas tank.

This post was edited by used red MN on 06/08/2023 at 08:15 am.

 

[BarnyardEngineering]

(quoted from post at 21:34:53 06/07/23) your coil wires are backwards.

While that is true that would not account for the loss of spark. The wires didn't spontaneously swap themselves while he was driving the tractor either.

Back to the OP, swapping the distributor is an extreme measure for troubleshooting. I would go through the trouble of swapping points and condenser, cap and rotor, LONG before I touched the distributor itself.

But first, I would have tried simpler troubleshooting. First run a folded $50 bill through the points. Still no spark, bypass the ignition switch with a wire straight from the battery to the coil. Next I'd try a different coil. I have had ignition switches and coils go bad.

 

[John T]

First of all, if it is POS ground ????? and wired correct ???? the coils - receives power when the ignition switch is ON while the coils + wires to the distributor where it gets a + ground when the points are closed BUT IT CAN STILL RUN EVEN IF WIRED BACKWARDS

Next a common cause of no spark IS BURNED PITTED CORRODED POINTS try cleaning them first but if badly burned pitted or carboned up install a new set... FWIW Ive seen more condensor problems (especially if it quits after warmed up) than coil problems

BEFORE throwing parts and money at it if you work through my Ignition Troubleshooting linked below it can help find the cause of no spark, give it a try.

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T
John Ts Ignition Troubleshooting

 

[used red MN]

A $100 bill works better ha ha. OF you have been here
a while so I assume you know the reason for the folded
money is not a joke. Actually a box flap off a set of
points etc. does the same thing, it is just a way to
clean anything off the contact surfaces of the points to
get them to contact. If you go by my suggestion of
using your meter or a test light you can leave the
money in your pocket. If the points are grounding the
coil circuit when they close you could run a stack of
50s through them and it would make your points work
NO better. John T does have a good run down for
troubleshooting an ignition. I just know that skipping
ahead to his step 4 to test as I suggested covers a lots
of the previous steps. But then again I have a fair
knowledge of what it takes to make the ignition work,
someone not as versed as me will need to follow the
steps.

 

[rustred]

ok, not a total loss of spark ,but a weak spark to prevent the engine starting. i just went through this on my 444 massey. the wires were
backwards and had a very weak spark. maybe the engine would have started but i know what the spark needs to look like and hear it. did not
even try to start it that way. switched the wires and she was a blue spark across the plugs that you could hear snapping. he ahs already
given one problem so why not switch the wires so they be correct ,... then proceed??? makes sense to me and easy and no troubleshooting.

 

[rvirgil_KS]

so I checked the coil and I have 6.2 volts going in and the coil reads 3.9 ohms from terminal to terminal.

First of all, is it definitely 3.9 ohms? Short ohm meter leads together and note the resistance, then check resistance across coil and subtract the short circuit reading, that should be your coil resistance. Many meters, especially cheaper ones, will show some resistance with probes shorted.

If it is 3.9 ohms it is a coil for 12 volt system with no external resistor. for 6 volts going in you should have a 1.5 ohm coil. Excessive resistance in coil circuit will cause problems.

As others have indicated your polarity is reversed on the coil. This can cause hard start on some engines, but is likely not your main problem.

 

[55 50 Ron]

Wow. Installing a new distributor is way over kill. Changing distributor means there could now be a timing issue.