What you are experiencing is a learning opportunity! LOL
The three things necessary to run, compression, spark, fuel.
Compression:
Since it was running a couple weeks ago, chances are it's not compression. But a trained ear can instantly tell by listening to the starter crank it through. You can hear the effort of the starter as each cylinder comes up on compression.
If one cylinder spins by without straining the starter, then you can assume for some reason that cylinder is down on compression.
If the engine spins free, like it would with the spark plugs removed, then it has lost compression on all cylinders, as in cam timing problems.
Spark:
One of the most common problems. Pull the coil wire out of the distributor, lay it about 1/2 inch from something metal, spin the engine through. It should give a blue hot spark to ground.
If good, put the wire back and pull each plug wire at the plug end. You can make a spark tester with an old plug. Break the electrode off the end, put the plug wire on the plug, ground the base. It should jump a spark from the center to the base. If yes, you can assume it has sufficient spark to start.
If no, open the distributor cap.
If there was spark from the coil, but not at the plugs, look for signs of moisture under the cap (very likely if it is stored outside or was recently washed). Just dry it out with compressed air, or dry it bast you can with a dry towel, spray it out with WD40.
Look for signs of carbon tracking under the cap, it will look like a jagged black crack. It can be under the cap, sometimes on the rotor. If found, they will need to be replaced.
If no spark from the coil, check the point gap. Also check that the points are making contact. With the ignition on, watch the points, you should see a small spark each time they open. Points are a very common cause of no spark. The new points are all aftermarket, some are very poor quality. Same for condensers, common to be bad out of the box new.
Sometimes pints can simply be cleaned with a point file. They tend to corrode when parked.
Another common problem is wear in the distributor shaft bushings. There should be very little side to side movement of the point cam. If any movement the points will not stay set.
Fuel:
Fuel problems are usually caused from a contaminated tank, or sitting for extended periods.
Fuel contamination is either water, or rust/trash in the tank, or occasionally something other than gasoline ends up in the tank.
Today's gas has ethanol, no practical way around it. The good, it is a great water absorbent. A little water will be absorbed and burn right on through the engine. The bad, it doesn't play well with open, vented fuel systems. It evaporates and leaves the ethanol goo behind. It tends to stick floats, and clog jets. It also degrades neoprene fuel lines, pump diaphragms, and carb parts.
The best defense is to turn the fuel off and run the carb dry, or drain it when the tractor will be stored for more than a few months. The tank can be treated with Stabil or other fuel storage treatments.
Back to the no start...
If an engine has spark, and compression, a logical assumption is it either has too much fuel, or not enough fuel in the cylinders to ignite.
Too much fuel, or "flooded" means the mixture is too rich to ignite.
This can be a temporary condition caused by too much choke, or it can be caused from a malfunctioning carburetor. Be sure the choke is properly adjusted, the choke should close fully, and open fully when operated.
A flooding carb will drip gas anytime the fuel valve is on, or it may still run, but blubber black smoke, consume excess fuel. In extreme cases, it can drain fuel from the tank and fill the engine. That's why you should always turn the fuel off at the tank when done for the day. If you left the fuel valve open, and suspect this has happened, check the oil level. If the level is high, and smells like gas, it will need to be changed before running.
Flooding is usually caused by trash under the needle valve from a contaminated tank. It can also be caused by a damaged needle valve or a sunk float.
Not enough fuel, the obvious, not enough in the tank. Most tanks won't feed the last inch or so of fuel. It helps to keep the dirty fuel from getting in the carb. There is a screen, (or should be) above the sediment bowl, and sometimes one in the carb inlet fitting. If any inline filters have been added, they can be too restrictive for a gravity flow system.
A good test, get a clean glass, look under the carb, there will be a drain plug. With the fuel valve open, remove the plug, catch the flow in the glass.
It should have a full flow, then slow to a trickle as the bowl empties down. If there is no flow, or the flow stops, or slows to a drip, there is insufficient fuel delivery.
Look at what was caught. If it is cloudy, or water in the bottom, or rust chunks, dirt in the glass, the tank is contaminated and will eventually need to be taken off and cleaned. Whatever is in the glass will be in the carb. If clean gas doesn't fix it, the carb will need to come apart and be cleaned. Don't be afraid of it, they are simple and field serviceable. Lots of info online, just work over a clean surface so as not to loose anything. Many times it can be eased apart without needing a kit.
Hope this covers it, let us know...
