Farmall Cub

I agree, that with that amount of compression it should fire . It might be the spark plug wires where they go through the grommet on the head. could be going to ground there even if new wires. another thought is if the wires are carbon fiber core. I have had a lot of trouble with these on many different tractors. make shure they are wire core. Never use carbon wires on a magneto . the coil will fail.

easy thing to do is replace the plugs.

Did you check the dist shaft to maks srue it is running in a circle and not an oblong circle. Did mine last week and the shaft was bent so the lobes were nit opening the points on cyls.3&4. pulled the dist.and took apart to find it bent above the c.weights. took the advance shaft [wich was siezed] off after some persuasion and cleaned it all up and streighting the shaft freed up everything lubed and ass.it with new points and the gap was the same on 4 all lobes. Good to go and runs great on all cyls. Bill wlm cub

Clean or replace your plugs, and check the spark plug wires....Check and make sure the # 1 cylinder is at TDC....Where the rotor points will be # 1 cylinder on the dist cap....Then install the wires in the correct firing order...Best I can come up with...(4 strokes of and Internal combustion engine....Intake, Compression, Power, and Exhaust....Redneck version.....Suck, Squeeze, Pop, and Phooey).....posting.php?mode=reply&f=1&t=77295# Dave