If you have a spark it should try and start - Check for loose carb - Check for fuel pressure to carb - Vacuum lines for leaks -
A lawn mower will jump a quarter inch in the air. You need to see 3 quarter inches as spark must ignite under high compression. Check the coil for burn marks and broken top, cap for burned pins. Check each wire for spark. Multiple spark testers are handy.
I'd first check the spark at the plug with the spark plug wire removed. You want a bright blue spark which will jump at least 1/4" to the plug. Any less jump or an orange/yellow spark will give you issues.
i hear alot about the wiring at the distributor breaking
just repaired one like that the other day that would not run
the wiring there is tiny guage wires, doesn't take much to break them
Wiggled & pulled on the wires to the distributor & wiggled the wires on the electric slow lock. After much cranking it started & ran fine while using it in the shop. Left it idling & it cut off. Cranked it & it sputtered & backfired & eventually ran briefly. Now it will not start again. Guess I have some wire chasing to do. I have two of these lifts & they constantly have a broken wire somewhere
Does it act like it wants to run as long as the key is in the cranking position but dies as soon as you release the key back to the run position? If so, check the wires going to the distributor to see if one has broken. One of those wires is a tach signal wire and if it breaks, the engine will act like it wants to run (or show an indicated spark) only while the engine is cranking. It might also help to know if this truck has a vacuum lockoff on the LP regulator or if it has an electric slow lock. Either type of regulator will have a big fuel inlet solenoid valve (down toward the rear of the regulator near fan) but only the late editions with TWC will have a small solenoid valve near the top front of the regulator.
Knowing which type of regulator lockoff will help in diagnosing as the two types are greatly different in their electrical circuits pertaining to ignition and fuel delivery.
Are you getting any fuel to the mixer?