Farmall M wont Start

[hobylobymarket]

I have an M thats been sitting for 2 years, ran before I parked it. Went out to start it, and gas was pouring from the bottom of the Carb like a faucet. So I sent the carb in to get rebuilt. This fixed the gas leak, but still
wouldn't start. So I replaced the spark plugs, and cleaned the spark plug wires with phosphoric acid. Still wouldn't start, turns over and just puffs white smoke out the exhaust without firing. Next I checked the
ignition points, and they look almost brand new. So Finally I tried pulling it in gear behind my truck to see if it would fire, and nothing. Just white smoke out the exhaust without it firing. I'm out of ideas, anybody got
anything?????

 

[old]

Learn how to trouble shoot before parts ALWAYS or you can add to the problem.

#1 check that you have a good blue/white spark from the center wire of the distributor cap and at all 4 plug wires.

#2 make sure you have a good steady flow of gas from the drain plug in the bottom of the carb. Flow needs to fill a pint jar in less then 3 minutes and 2 is better. Yes catch it to look for water/dirt.

#3 have you check the air cleaner and made sure it was not full of water/mud?

#4 pull the carb intake tube off and spin it over holding your hand over the air intake. You should both feel a good suction and get gas on your hand. Lack of either say low compression or clogged carb

 

[used red MN]

You need to check for spark at the coil. Remove the coil wire out of the center terminal of the distributor cap. Hold it about an inch and a half from the end and place the terminal on the end of the wire about a quarter inch from the engine block. Have a helper crank the engine over with the starter and the ignition switch on. You should have a strong blue spark that jumps that 1/4 inch. Check and report back. Or if no fire determine if you have voltage at the points with the ignition switch on, if the points are closed or touching at the contact surface there should be no power for a test light on them. If you take a screwdriver and open them by moving them against their spring then you should see a slight spark at the contacts this tells you you are getting power points for the coil. When working properly a test light held to the terminal coming out of the distributor should flash off and on as they open and close while cranking with the ignition switch on. Just to clarify this is not a M diesel that switchs from gas to diesel is it?

 

[gab]

My Super M only gets started once or twice a year other wise just sets in my shed. Wouldn't start a few years ago, checked all the normal stuff and looked good, cranked and cranked and finally got it hitting on a couple cylinders when a cloud of stinking smoking black feathers blew out of the muffler plus a starling skeleton I think. He must of snuck in there when I had a door open, luck the place didn't burn down.

 

[rustred]

very first is to clean the point contacts. when they sit in the closed position they form a film on them . lots of times just snapping them open from the closed position with the ignition on will get you going. plus you will see and hear the snap. lots of times i run emery cloth through them then a paper towel with brake clean on it. that all it takes. spark plugs and wires do not prevent an engine from starting. this is so common, nowadays the younger people with points and carbs are lost.

 

[hobylobymarket]

So I tried cleaning the contacts, they had a lot of what looked to be almost a soot build up on them. Put the distributor back together, cranked it over, and nothing. Still won't fire with white smoke. I'm running out of ideas at this point.

 

[old]

It is very simple to test a set of points. Pull the distributor cap off and the rotor and dust cover. Hook a wire to the ignition side of the battery. With the points closed touch the ignition side of the coil with that wire. You should see a small spark every time you do. Next turn the engine not the point that the points are open and do the wire touch test again. This tiem you should not get a spark. If you don't get the spark when the points are closed there bad or dirty. If you get a spark when open you have a short in the distributor

 

[used red MN]

Still need to check for spark as was suggested by myself and another reply.

 

[FBH44]

Try this, it fixed my H; replace the distributor cap and rotor. My center electrode had wore down too far, would not make contact. Reeplaced them, voila FIXED! Fired right up. Cheap. Use the all brass cap, not the aluminum one.

 

[BarnyardEngineering]

No offense, but "crank and pray" is neither an idea nor a troubleshooting technique.

First, check for spark. Take the coil wire off the center post of the distributor and hold it near anything metal attached to the tractor while cranking. You should get a consistent strong blue-white spark.

Next, put the wire back on and remove a spark plug. Reinsert the spark plug back into its wire and lay its threaded base on a metal part of the tractor while cranking. Again you should get a consistent strong blue-white spark, only 1/4 as many as you got from the coil.

White smoke from a gas tractor is unusual. Is this an MD? Are you trying to start it on diesel?

 

[used red MN]

Rust, I looked back at his old posts. He makes no mention
of it being a diesel, I can only assume he is talking about
the same tractor. He has converted it to 12 volts which
according to his posts must have been around 2017. I
assume it has ran since then. White smoke could be from
water or antifreeze in the cylinders, but not a real common
issue on an M. Not saying it cannot be happening and
generally shows up when running and warmed up. By the way good analogy with the ..crank and pray.. line!

 

[Russ from MN]

Another tip, after all this cranking with no success you have dried out the cylinders, so take the spark plugs out and squirt some oil in them. I have had that work on stubborn engines that have sat too long.

 

[rustred]

yes but did you check for spark at the points as i said? have ignition on and open the points from the closed postion you will see and hear the spark. you are missing this step since you have the cap off anyhow. are the point contacts shiny or still black... more important info. how did you clean them. best is a point file. next will be test light test.

 

[Russ from MN]

Are you sure you have gasoline in the carburetor? Sounds like diesel to me!