Need help with my cub

sounds like dirty points could be the problem. Gotta file them every once in a while to keep them clean. That should get spark going then it should start.
 
Run the chain/cable/rope, etc from the front between the front wheels and connect it to a solid casting part like the drawbar or around the torque tube. The idea is not to put any stress on the front end since the castings there are not very large thus more likely to be damaged by sudden/unusual pressure/stress. My preference is a sturdy rope since it has some "stretch" and less likely to cause damage. Other means are acceptable, just use caution. JMHO Stan
Thank you. If this doesn't make her start, we're out of ideas. He checked everything again and everything checks out.
 
This may seem stupid but have you checked the gas tank to make sure it has enough fuel? Been there and done that before myself.
You may want to pop the distributor cap off and verify the point gap and clean the points as well.
Not stupid at all. Actually, that was my first question when this happened. lol
 
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sounds like dirty points could be the problem. Gotta file them every once in a while to keep them clean. That should get spark going then it should start.
All clean. We have spark...forgot to add I picked up new plugs last week so those are new and sparking. Everything he's checked, electrical and fuel, seems to be in order. I told him it's going to be something very simple. This has us scratching our heads.
 
Hello all from the hot humid deep south. Maybe check to see if the holdown bolt for the magneto is still tight , magneto maybe turned just enough to be off ? I know y'all checked timing , but........ coppersmythe....................................PS: a bit of a reach , but i've experienced worse ;);)
 
take the pipe plug out of the manifold ABOVE the carb and dump a shot of gas in there. Thats the only way I can get any of mine started.--- next thing would be to get the chain out and pull start that sucker!! Might just be flooded and not turning over fast enough.
 
I know you've checked and rechecked for spark, wiring, and fuel.
If it were me l'd start over from the beginning with the basics. Take it to TDC and line up your timing mark on the pulley. Pull the cap and verify that the rotor is in the 1 oclock position. If so, pull the mag and recheck the points and gap. You may want to replace the points and condensor (easiest and cheapest place to start). Verify rotor alignment to the pinion gear. Reinstall the mag and static time it according to manual specks. Hold the coil wire about a 1/4" off the block to check for a strong "bluish" spark. After going through those steps, if you still get no "cough" or fire, move to fuel.
Check that you have flow from the tank to the bowl (l had a dead bug in mine once that restricted flow). Disconnect the fuel line from the carb, again verify you have good flow through the line. Check the carb fuel intake for clog. Reattach the fuel line. Pull the plug at the bottom of the carb to check flow into the carb bowl.
After going through all of that step by step and it still doesn't "pop" then l'm as stumped as you and everyone else.
I say all this because years ago because l've been where you are with my '48. I once had it 180° out of time, and most recently had a bad pinion gear and rotor (both missing one tooth) that moved it just enough where l was getting spark, but at the wrong time. If l hadn't slowed down and gone step by step, l'd probably still be pulling my hair out.

Good luck
Hutch
 
Yes, what Hutch said. You probably have replaced the original problem with some mistake made while trying to find the problem. It probably was flooded in the first place. Since it had been running, all the timing etc. was correct. But anything that has been touched needs to be rechecked from scratch. Timing is a good place to start. There may be some detail that you have forgotten. Review the instructions in the Owner's Manual. Make sure the rotor and pinion marks are lined up. Find TDC on the COMPRESSION stroke for cylinder 1 and see where the rotor is pointing. If it isn't at 2 o'clock, remove the magneto and turn it backwards until it is in place then reinstall it. Do a check of the static timing. Make sure the spark plug wires are in the right order.
 
I don't know if this idea will contribute anything, but I had a similar problem on one of my tractors. There was a felt spacer underneath the rotor that had fallen out when I was checking the distributor cap on a magneto. And the rotor wasn't "tall enough" to make a good contact with the poles on the distributor cap. It created spark, but not well enough to effectively fire the plugs well. Replacing the cap, rotor and that felt spacer fixed my problem. And it was discovered after using an old electronic timing light to check timing consistancy on the flywheel marks behind the clutch. And I had to crank it awhile (at least a few minutes} to find the problem.
 
Easy enough to check main jet for a chunk of dirt or varnish that got sucked against it trying to restart. Probe it out with a piece of copper wire smaller than the orifice .
If not an obstruction there then check at carb fuel line entrance for a restricted screen. (a screen may or may not exist). If not there head to fuel strainer for a look see. If not there then to tank outlet.( Look close at fuel strainer as it can be crudded up holes in screen but not easy to see if not removed.)

You should note good fuel smell when the main jet is pulled. If watery...It won't burn well unless engine is already running.
 
Hello all from the hot humid deep south. Maybe check to see if the holdown bolt for the magneto is still tight , magneto maybe turned just enough to be off ? I know y'all checked timing , but........ coppersmythe....................................PS: a bit of a reach , but i've experienced worse ;);)
Hello there...and yes it's hot here in the deep south lol I will give him this info. Yes, he's checked the timing 4 times now and it looks to be right.
 
is it a good blue spark, not just orange?, has good compression?
Good blue spark and has good compression.
take the pipe plug out of the manifold ABOVE the carb and dump a shot of gas in there. Thats the only way I can get any of mine started.--- next thing would be to get the chain out and pull start that sucker!! Might just be flooded and not turning over fast enough.
I will tell him to try this. He's got to wait until I'm home long enough to try to pull start her. lol Hopefully we can do it this weekend if any of the other suggestions don't get her up and running.
 
I know you've checked and rechecked for spark, wiring, and fuel.
If it were me l'd start over from the beginning with the basics. Take it to TDC and line up your timing mark on the pulley. Pull the cap and verify that the rotor is in the 1 oclock position. If so, pull the mag and recheck the points and gap. You may want to replace the points and condensor (easiest and cheapest place to start). Verify rotor alignment to the pinion gear. Reinstall the mag and static time it according to manual specks. Hold the coil wire about a 1/4" off the block to check for a strong "bluish" spark. After going through those steps, if you still get no "cough" or fire, move to fuel.
Check that you have flow from the tank to the bowl (l had a dead bug in mine once that restricted flow). Disconnect the fuel line from the carb, again verify you have good flow through the line. Check the carb fuel intake for clog. Reattach the fuel line. Pull the plug at the bottom of the carb to check flow into the carb bowl.
After going through all of that step by step and it still doesn't "pop" then l'm as stumped as you and everyone else.
I say all this because years ago because l've been where you are with my '48. I once had it 180° out of time, and most recently had a bad pinion gear and rotor (both missing one tooth) that moved it just enough where l was getting spark, but at the wrong time. If l hadn't slowed down and gone step by step, l'd probably still be pulling my hair out.

Good luck
Hutch
Will let him read all of this, along with all other posts. As for the flow from the tank to the bowl, there's good fuel flow all the way to the carb. Thanks for the suggestions!
 
Yes, what Hutch said. You probably have replaced the original problem with some mistake made while trying to find the problem. It probably was flooded in the first place. Since it had been running, all the timing etc. was correct. But anything that has been touched needs to be rechecked from scratch. Timing is a good place to start. There may be some detail that you have forgotten. Review the instructions in the Owner's Manual. Make sure the rotor and pinion marks are lined up. Find TDC on the COMPRESSION stroke for cylinder 1 and see where the rotor is pointing. If it isn't at 2 o'clock, remove the magneto and turn it backwards until it is in place then reinstall it. Do a check of the static timing. Make sure the spark plug wires are in the right order.
He's checked the timing at least 4 times and it appears to be timed correctly. Will let him read all of this. Spark plug wires are in the right order. Thanks for the suggestions. Will be checking into all of this again.
 
I don't know if this idea will contribute anything, but I had a similar problem on one of my tractors. There was a felt spacer underneath the rotor that had fallen out when I was checking the distributor cap on a magneto. And the rotor wasn't "tall enough" to make a good contact with the poles on the distributor cap. It created spark, but not well enough to effectively fire the plugs well. Replacing the cap, rotor and that felt spacer fixed my problem. And it was discovered after using an old electronic timing light to check timing consistancy on the flywheel marks behind the clutch. And I had to crank it awhile (at least a few minutes} to find the problem.
Definitely something to check into. Thanks!
 
Easy enough to check main jet for a chunk of dirt or varnish that got sucked against it trying to restart. Probe it out with a piece of copper wire smaller than the orifice .
If not an obstruction there then check at carb fuel line entrance for a restricted screen. (a screen may or may not exist). If not there head to fuel strainer for a look see. If not there then to tank outlet.( Look close at fuel strainer as it can be crudded up holes in screen but not easy to see if not removed.)

You should note good fuel smell when the main jet is pulled. If watery...It won't burn well unless engine is already running.
She has good fuel flow so is it still possible it's restricted by dirt or something?
 
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