mariner 75, wont start and stumped

[AndrweB]

ok, my buddy has a mariner 75, not sure of the year, but it will not start. we have pulled the plugs and they have spark, its getting fuel. we pulled the plugs and sprayed fuel in the cylinder and it didnt even try to start. it is turning over all day long. his dad said last time he drove it he had to give it a lil bit of gas to get it to crank and it wouldnt idle. but now it wont do anything but turnover. and like i said we have spark at the plugs, and we even sprayed fuel behind the plugs to see if it would even give us a sputter or something but nothing.

 

[guyjg]

...we have spark at the plugs...

Test the spark w/a tester. It should jump 7/16" and be slightly blue and bright. If it has a yellow tinge and dim then it is not very strong. It won't run w/o compression; what is it?