Farmall M Not Firing.

My Farmall M will not fire. Installed new carb. to manual settings, have spark at plugs, carb. bowl has gas but will not fire. Will not fire even with starting fluid. Sometimes I get an occasionally putt as if one cylinder fires. Any suggestions? [/b]

After cranking for five seconds are the plugs wet with gas?

A bit more information sure helps. Has it
run recently? Did it quit while running?
Has it been screwed with since it last
run such as timing messed with? Wires
removed? Etc etc???
With basically nothing to go on you need
4 things. Fuel, compression,(good!) spark
and timing. Spark must jump at least
1/4" when you have that pull the plugs
and check compression. Assuming you have
that squirt 3-4 pumps of oil in the
cylinders before before reinserting the
plugs. Next have someone turn it over
while you hold your hand over the
carburetor inlet, you should have strong
suction, if not the list of possibilities
is long. If you have that then find TDC
of compression stroke pull the cap and
look to see that the rotor is pointed at
#1 and the wires are in the correct
order. Find a manual and set timing to
before TDC while cranking if battery
ignition or at TDC when impulse trips if
it is a magneto. Make sure there is fuel
in the carb atvthe drain. If all the
above checks out and won't fire even on
start fluid go back to step one and
figure out what you missed..

(quoted from post at 08:00:04 06/01/20)

After cranking for five seconds are the plugs wet with gas?

Click to expand...

Plugs are not wet with gas.

Just had an "H" that had spark to the plugs but would not fire. Put in new plugs and fired right up...old plugs had soot on the electrodes and would barely fire. Probably would have run with the old ones if I would have cleaned the electrodes.

Have you got your spark plug wires back on in the correct order and in the right holes in the cap?

Warm up the plugs with a propane torch so hot you need to put a rubber hose on the insulator to put them in. If no joy, (and you are sure the spark plug wires are in these holes (most common arrangement)) #1 is front of engine.
2-1
4-3
This is looking toward the front of the tractor at the cap. #1 is top right, and numbering is clockwise. Jim

So you have gas to the bowl but not to the cylinders. This points to a sticking or out of adjustment float or float valve. Before pulling the carb though, try finding out exactly how high the gas level in the float bowl is by replacing the bowl drain with a barbed fitting and putting a short piece ov vinyl tubing on the barb. With the tubing beside the carb you can see the level.

(quoted from post at 10:29:15 06/01/20)

So you have gas to the bowl but not to the cylinders. This points to a sticking or out of adjustment float or float valve. Before pulling the carb though, try finding out exactly how high the gas level in the float bowl is by replacing the bowl drain with a barbed fitting and putting a short piece ov vinyl tubing on the barb. With the tubing beside the carb you can see the level.

Click to expand...

veryone wants to investigate fuel as a problem. Why? Seems to me he eliminated that before his initial post, by stating that it wouldn't run on starting fluid. What did I miss?

(quoted from post at 08:25:47 06/01/20)

(quoted from post at 10:29:15 06/01/20)

So you have gas to the bowl but not to the cylinders. This points to a sticking or out of adjustment float or float valve. Before pulling the carb though, try finding out exactly how high the gas level in the float bowl is by replacing the bowl drain with a barbed fitting and putting a short piece ov vinyl tubing on the barb. With the tubing beside the carb you can see the level.

Click to expand...

veryone wants to investigate fuel as a problem. Why? Seems to me he eliminated that before his initial post, by stating that it wouldn't run on starting fluid. What did I miss?

Click to expand...

Thanks for asking JMOR, always glad to help you out. Perhaps you missed that he said that he got the "occasional put", or perhaps you missed that Butch already gave him excellent ignition trouble shooting information, as did janicholson. Also maybe you missed that he responded that his plugs were dry even after five seconds of cranking which should virtually always get plenty of gas into the cylinders. We know that fuel is needed for it to run but we don't know how much of a shot of ether he gave it. Just a few weeks ago I had a start problem and a sniff of ether produced just one pop. It turned out that it was not getting gas. So seeing that he was getting plenty of ignition help, I could see that this is not an "everyone wanting to investigate fuel as a problem situation but was, as you can probably see now, just the opposite. We certainly don't want anyone going way down any one track without first performing quick simple checks. Right ole' buddy?

I agree with Butch, tell us more of the story. Did it run before and what else was messed with. Here is something easy to try. Take out a spark plug, get a hose 1/4 or 5/16 inch ID at least a foot long. Immerse it gas 4 to 6 inches and hold your finger on the end and pull out to transfer gas into the spark plug hole. Screw the plug in a couple turns by finger and put the plug wire back on. Now when you try to start it if you get a couple good hits out of that cylinder you know you’re not getting gas up in the cylinders.

(quoted from post at 12:34:27 06/01/20)

(quoted from post at 08:25:47 06/01/20)

(quoted from post at 10:29:15 06/01/20)

So you have gas to the bowl but not to the cylinders. This points to a sticking or out of adjustment float or float valve. Before pulling the carb though, try finding out exactly how high the gas level in the float bowl is by replacing the bowl drain with a barbed fitting and putting a short piece ov vinyl tubing on the barb. With the tubing beside the carb you can see the level.

Click to expand...

veryone wants to investigate fuel as a problem. Why? Seems to me he eliminated that before his initial post, by stating that it wouldn't run on starting fluid. What did I miss?

Click to expand...

Thanks for asking JMOR, always glad to help you out. Perhaps you missed that he said that he got the "occasional put", or perhaps you missed that Butch already gave him excellent ignition trouble shooting information, as did janicholson. Also maybe you missed that he responded that his plugs were dry even after five seconds of cranking which should virtually always get plenty of gas into the cylinders. We know that fuel is needed for it to run but we don't know how much of a shot of ether he gave it. Just a few weeks ago I had a start problem and a sniff of ether produced just one pop. It turned out that it was not getting gas. So seeing that he was getting plenty of ignition help, I could see that this is not an "everyone wanting to investigate fuel as a problem situation but was, as you can probably see now, just the opposite. We certainly don't want anyone going way down any one track without first performing quick simple checks. Right ole' buddy?

Click to expand...

ell, I guess a lot depends on what one knows, but if it is only a fuel problem, then an engine will run all day long on ether, as long as you have enough cans to keep on spraying. ...or a person can shotgun it and chase everything in all directions. I prefer to eliminate one thing at a time instead of jumping here and there helter skelter. But to each his own.

(quoted from post at 10:15:42 06/01/20)

(quoted from post at 12:34:27 06/01/20)

(quoted from post at 08:25:47 06/01/20)

(quoted from post at 10:29:15 06/01/20)

So you have gas to the bowl but not to the cylinders. This points to a sticking or out of adjustment float or float valve. Before pulling the carb though, try finding out exactly how high the gas level in the float bowl is by replacing the bowl drain with a barbed fitting and putting a short piece ov vinyl tubing on the barb. With the tubing beside the carb you can see the level.

Click to expand...

veryone wants to investigate fuel as a problem. Why? Seems to me he eliminated that before his initial post, by stating that it wouldn't run on starting fluid. What did I miss?

Click to expand...

Thanks for asking JMOR, always glad to help you out. Perhaps you missed that he said that he got the "occasional put", or perhaps you missed that Butch already gave him excellent ignition trouble shooting information, as did janicholson. Also maybe you missed that he responded that his plugs were dry even after five seconds of cranking which should virtually always get plenty of gas into the cylinders. We know that fuel is needed for it to run but we don't know how much of a shot of ether he gave it. Just a few weeks ago I had a start problem and a sniff of ether produced just one pop. It turned out that it was not getting gas. So seeing that he was getting plenty of ignition help, I could see that this is not an "everyone wanting to investigate fuel as a problem situation but was, as you can probably see now, just the opposite. We certainly don't want anyone going way down any one track without first performing quick simple checks. Right ole' buddy?

Click to expand...

ell, I guess a lot depends on what one knows, but if it is only a fuel problem, then an engine will run all day long on ether, as long as you have enough cans to keep on spraying. ...or a person can shotgun it and chase everything in all directions. I prefer to eliminate one thing at a time instead of jumping here and there helter skelter. But to each his own.

Click to expand...

JMOR, glad you agree with me!