Farmall M partial rebuild wont start

I have a Farmall M that we were working on restoring after sitting in a shed a few years. Ran when they parked it type of deal.

We have removed and cleaned most of the not chassis parts and reinstalled all of them repairing as we go. We are now to the point we feel the engine should start and we cannot get it to run.

We took the front crankcase cover off but did no engine work other than gasket replacements on the side and top covers. Basically, flushed as much junk out of the cooling system as we could.

We have ordered a new starter, rebuilt the carburetor, have a rubber fuel line connecting the tank to the carb, flushed and reinstalled the radiator, updated the magneto under the distributor cap, put a new cap and wires and new plugs.

When we crank it we get enough suction on the air cleaner side of the carb to oull your hand tight to it. We appear to be getting good gas to the carb. I would not call the plugs dry.

On the electrical side we followed an online diagram on this website to rewire it. It is 12 volt conversion with a resistor that is good. We can get the work light on we get spark on the plugs when we hold the wire next to the plug, we have confirmed 3 times we have the cables on correctly.

We have put oil in the plugs and gas and gas and oil mix and attempted to get it to fire. To date I think we have had 2 real fires and that s it. We are running out of ideas and would like any help. We aren t to the give up point but my son is getting fairly discouraged.

When you hold your hand over the carb, is your hand wet with gas after cranking on it?

If the plugs are wet with the ignition on, you don't have spark.

Hold it over the air intake side?

1. Does it have a ..magneto.. or a distributor ignition
that is powered by the battery?

2. Did you remove the mag or distributor from the
engine?

3. What is you method of confirming the spark plug
wires are connecting the correct distributor cap
terminal to the proper spark plug?

4. What does this mean? ..updated the magneto under
the distributor cap..

5. Have you tested proper fuel flow to the carburetor
bowl by removing the plug on the bottom of the carb
to see if it continues to flow after 15 seconds and does
not slow to just a dribble? In association with this do
you know that the fitting that screws in the carb where
the fuel line connects has screen that needs to be
checked?

6. Do you have the main needle valve that screws
straight in the bottom of the carb from the front preset
at 4 turns out from being screwed in clockwise and
seated lightly?

I am at work so I am going by memory a bit here.


1. Does it have a ..magneto.. or a distributor ignition
that is powered by the battery?

It has a distributor. We put an ignition tune up kit in it from Stiener tractor parts.


2. Did you remove the mag or distributor from the
engine?

Yes

3. What is you method of confirming the spark plug
wires are connecting the correct distributor cap
terminal to the proper spark plug?

We video recorded ourselves removing them. In the upper right corner the cap is marked 1. That was placed on the front most plug. Then in a clockwise fashion around the cap we attached the cables as stamped on the side of the tractor reading left to right. Middle went to the coil. We then held each on cable end a few CM away from the end of the plug to make sure we had a spark at each plug.

4. What does this mean? ..updated the magneto under
the distributor cap.

It means I am new to tractor restoration although I am really into it. We put a new ignition kit in the distributor. Stiener Parts is absolute terrible about including any type of instructions with there parts so we could not confirm we have all the spacings correct in there. We plan to double check that tonight.

5. Have you tested proper fuel flow to the carburetor
bowl by removing the plug on the bottom of the carb
to see if it continues to flow after 15 seconds and does
not slow to just a dribble? In association with this do
you know that the fitting that screws in the carb where
the fuel line connects has screen that needs to be
checked?

We haven't done part one but we can/will(The solder joint inside the starter gave away so I ordered a new starter last night and will rebuild and sell the old one). When we stop cranking, we get gas out of the bottom of the carb for around 5 seconds like the bowl is draining out clean. The filter has been replaced. WE also have eliminated the sediment bowl and the original fuel line and just have rubber fuel hose between the two currently. Trying to eliminate items without having to buy a whole bunch of new parts.

6. Do you have the main needle valve that screws
straight in the bottom of the carb from the front preset
at 4 turns out from being screwed in clockwise and
seated lightly?

I will double check. I think we have it at 3 as recommended by stiener but surely can back it out one more turn.

When we stop cranking it we get some gas blowback towards the air filter.

So for 2 and 3 you pulled the distributor and put it back in the same place without moving the engine? If you did turn the engine while it was off and just turned the crank until the timing pointer and pulley lined up your timing can be 180 degrees off. A 4 cycle engine has two top dead centers within the 4 cycles of the piston. One at the top of the compression stroke and another one at the top of the exhaust stroke. So the distributor has to be in time not only with the crank but also the camshaft and valves. If you need to straighten this out pull number one spark plug. The best way to do this is with the hand crank. Now one guy holds his finger in the number one plug hole while the engine is turned. When a positive pressure is felt blowing out now continue to turn it until you line up the pulley with the first of the two notches close together. Now insert the distributor so the rotor points about 1:00 to 1:30 position viewed from the back. This will be where you place number one spark plug. Put it together with the wires in the order 1-3-4-2 clockwise again from the back and start it up.
Also I did not mention this but since you have a good suction at the carb this is probably not keeping it from running. The item is setting the valve clearances. If you get it started warm it up good and pull the valve cover. Intake and exhaust both set 0.017 inches.

Also adding and hopefully you know this cylinder 1 is the front one, closest to the radiator. Two is the second from the front.

I am sure this isnt correctly put together. Ill work on it tonight.

Thanks

That could be a clue!

Maybe a restricted exhaust. If it was stored a while critters may have packed the exhaust with acorns!

It started tonight. The look on that 14 year olds eyes was priceless. We have some tuning to do as it appears to be stuck on high idle but it started and ran for several minutes until we shut it down to tighten a few hose clamps. Thank you very much it was exactly what you said with the distributor.

That is good to hear glad I could help, just a matter of sharing details that are often overlooked or unknown. The sticking on high idle could very likely be that the carburetor throttle shaft is not connected properly to the throttle control shaft from the governor. In the link throttle shaft 23 has a tab on the end that inserts in the notch of a fat V on the end of the carb shaft. This is very difficult to get in there correctly a good light and patience is helpful. If you need to you can take out the bolts that hold part 19 to the top of the main governor housing. To get enough give in it you may also need to take out the screws to the vent cover part 3. Hope I am calling this correctly.
CNHI Farmall M online parts diagram