snowmobile wont start, but there is a spark?

[Paul]

hello, my snowmobile is getting a spark but the damn thing wont start. i even used starting fluid in the air intake. it is a 1972 sno jet 440 sst.

 

[brucec30]

Well, you say it has spark and you gave it fuel. This leaves breathing (intake/exhaust) and timing. You are testing the spark in open air, what tool are you using? Can you vary the gap?
The combustion chamber provides a great deal of resistance to the spark, it may take an easier path when it is presented with compression pressures.
I would expect your timing is thru gears, you would also hear differences in cranking since compression would not be up to par.
Look more closely at your spark.

 

[ChrisWF]

Check fuel pressure. One way to test this is to unplug fuel filter and try to hold fuel in with your finger. Pressure should be strong enough to spray all over.

If it is strong pressure BEFORE the fuel filter, then the filter/injectors are bad.

Carbeurator could be bad as well but I don't know how to test a small vehicle carbeurator.

Check air filter for any clogging. Replace if needed.

Lastly make sure your firing order is correct. Unsure of your number of cylinders but reversed/mixed up plug wires will keep something from running.