Ken Christopherson
Well-known Member
Headed back over to troubleshoot the 1947 Farmall M in the morning. I'm hoping to have it running tomorrow. For those who missed it, I seem to be having an issue getting fuel from the carb to the cylinders. Here is a brief overview of where I am at:
Valves: Set at .018, cold. (calls for .017 hot).
Mag impulse: set to fire #1 as the first of the two 'double notches' on the crank pulley passes the timing needle on the front timing cover. Plug wires set up as 1-3-4-2 in a clockwise rotation (looking at the back of the rotor). Checked for spark - hot purple/blue spark. Spark plugs gap set at .025.
Carburetor: Idle mixture screw adjusted to 1 1/2 turns out. Load mixture screw adjusted to 2 3/4 turns out (factory recommended settings).
Cam and crank timing: single punch mark on cam lined up with single punch mark on crank - #1 cylinder at TDC.
Cam and magneto drive timing: double punch mark on cam lined up with double punch marks on magneto drive.
Even with full choke (no matter the throttle position), I seem to not be getting fuel past the carburetor. I know I've got good flow, I removed the line and got a steady stream. The carburetor does flood out and drain out the intake after a few cranks on full choke (so I know there is plenty of gas). I pulled the spark plugs, and they are dry as a bone, and have no smell of gas. I didn't try to pull start it but I cannot fathom why I'm not getting gas from the carburetor to the cylinders. I did spray some carburetor cleaner into the carb intake to see if I could get fire that way and I did get one loud "bang" out of the exhaust.
I've watched my timing videos a few times now (Episodes 13 and 14), and after paying close attention I can only come to the conclusion that the crank, cam, and magneto drive are set correctly. In the morning, I will start with putting a few squirts of oil into each cylinder. I will then double check my valves and make sure they are adjusted properly. From there I will move to the magneto impulse - making sure it fires just as the first of the double notches passes the pointer on the front timing cover. After that I will double check the spark plug gap to ensure it is set correctly. From there, I will install the (NEW) 12v battery and crank it to ensure I have good draw through the carb. If all checks out I will then pour some fuel in the cylinders to see if I can get it to fire. I really cannot think of anything else to try. Hopefully by then my friend will be off work and may be willing to assist me in pull-starting the tractor if I can't get some fire out of it. I'll be video-documenting the process so that everyone may offer suggestions should it not work. I am hoping to have it running tomorrow, though!
Valves: Set at .018, cold. (calls for .017 hot).
Mag impulse: set to fire #1 as the first of the two 'double notches' on the crank pulley passes the timing needle on the front timing cover. Plug wires set up as 1-3-4-2 in a clockwise rotation (looking at the back of the rotor). Checked for spark - hot purple/blue spark. Spark plugs gap set at .025.
Carburetor: Idle mixture screw adjusted to 1 1/2 turns out. Load mixture screw adjusted to 2 3/4 turns out (factory recommended settings).
Cam and crank timing: single punch mark on cam lined up with single punch mark on crank - #1 cylinder at TDC.
Cam and magneto drive timing: double punch mark on cam lined up with double punch marks on magneto drive.
Even with full choke (no matter the throttle position), I seem to not be getting fuel past the carburetor. I know I've got good flow, I removed the line and got a steady stream. The carburetor does flood out and drain out the intake after a few cranks on full choke (so I know there is plenty of gas). I pulled the spark plugs, and they are dry as a bone, and have no smell of gas. I didn't try to pull start it but I cannot fathom why I'm not getting gas from the carburetor to the cylinders. I did spray some carburetor cleaner into the carb intake to see if I could get fire that way and I did get one loud "bang" out of the exhaust.
I've watched my timing videos a few times now (Episodes 13 and 14), and after paying close attention I can only come to the conclusion that the crank, cam, and magneto drive are set correctly. In the morning, I will start with putting a few squirts of oil into each cylinder. I will then double check my valves and make sure they are adjusted properly. From there I will move to the magneto impulse - making sure it fires just as the first of the double notches passes the pointer on the front timing cover. After that I will double check the spark plug gap to ensure it is set correctly. From there, I will install the (NEW) 12v battery and crank it to ensure I have good draw through the carb. If all checks out I will then pour some fuel in the cylinders to see if I can get it to fire. I really cannot think of anything else to try. Hopefully by then my friend will be off work and may be willing to assist me in pull-starting the tractor if I can't get some fire out of it. I'll be video-documenting the process so that everyone may offer suggestions should it not work. I am hoping to have it running tomorrow, though!