My 47 Cub has been really hard to start most of this summer. Its 12 volts with a J4 mag so cranking is no problem. Tractor acts like it want to start and fires occasionally and if I crank it long enough it
will eventually start and run fine. Sometimes I can't get it to start until trying again the next day. I'm trying to figure out if I have a weak spark or a gas problem. No problem getting gas to the carb.
Everything is tight on the carb and manifold gaskets. When I got the tractor a few years ago it had low compression so had the valves done and shop went through the entire motor checking specs. That was a
about 4 years ago and motor doesn't have a lot of hours on it. When I got it there was a real cobble job of wiring and the tractor had been set up for an external coil and had a condenser attached outside the
mag so I replace the mag coil, points and condenser and went to a single wire alternator. I also replaced the carb as original had a lot of physical damage. Carb is IHC carb. Tractor started and ran great
after that and runs great now if I can get is started. I did try a different condenser I had in the drawer (previously used) and thought it helped but a few days later nothing had changed - still hard to
start. I was finding oil inside the cover where the points are and in the cap so I changed the oil seal at the front where the mag attaches and cleaned all the oil from the points area and made sure points
were clean. I hear the impulse coupling working. I'm looking for what else to look for. Mag is back together correctly as eventually the tractor starts and runs well. Looking for other ideas.
will eventually start and run fine. Sometimes I can't get it to start until trying again the next day. I'm trying to figure out if I have a weak spark or a gas problem. No problem getting gas to the carb.
Everything is tight on the carb and manifold gaskets. When I got the tractor a few years ago it had low compression so had the valves done and shop went through the entire motor checking specs. That was a
about 4 years ago and motor doesn't have a lot of hours on it. When I got it there was a real cobble job of wiring and the tractor had been set up for an external coil and had a condenser attached outside the
mag so I replace the mag coil, points and condenser and went to a single wire alternator. I also replaced the carb as original had a lot of physical damage. Carb is IHC carb. Tractor started and ran great
after that and runs great now if I can get is started. I did try a different condenser I had in the drawer (previously used) and thought it helped but a few days later nothing had changed - still hard to
start. I was finding oil inside the cover where the points are and in the cap so I changed the oil seal at the front where the mag attaches and cleaned all the oil from the points area and made sure points
were clean. I hear the impulse coupling working. I'm looking for what else to look for. Mag is back together correctly as eventually the tractor starts and runs well. Looking for other ideas.