First check compression. This can be done by putting a finger over the spark plug holes. There should be a good pop of air out of them. If you have compression and spark, next pour a little fuel in plug holes see if you can get it to try to run, if it does the fuel may not be getting through the carbs.
there could be many reasons, but you need to elaborate on your question, that is too vauge to answer... is it a snowmobile? is it an atv? are the spark plugs clean? is fuel flowing to the carb? does it backfire?
The ratio is 40:1 on this snowmobile.
Many things can cause a snowmobile engine to back fire. Ignition coils ( spark plugs, coils) or water in fuel. Check these and maybe it will solve your problems.
car has spark and fuel it will crank over but will not start
Does it have: fuel, spark, compression?
cause it has no fuel.
Does it turn over? Does it have spark? Does it have fuel? Does it turn over? Does it have spark? Does it have fuel?
If your KIA Sportage won't start but has a spark and fuel, it could be a the fuel pump relay or possibly a fuse.
its need 3 things to start fuel spark compression and they have to be all at the right time
My dad had an experience like that. Wait until the engine cools off. Then slowly start it. It worked with my dad.
If getting fuel and spark, then need compression and air.
Does it turn over? Does it have spark? Does it have fuel?