Johnson 90hp 1996 wont fire

[samt]

Having some issues with a 1996 johnson 90hp VRO V4.

Engine wont fire, although I have a strong spark on all 4 cylinders. Carbs have been clean and seem ok. Fresh fuel, and fuel pump appears to be working okay.. Oil tank full... Engine turning over okay.. Plugs appear dry, so I checked carbs again... no aparent problems..

Any ideas? I have no previous experience with these engines (and i know theyre not particually highly rated)

[Nos4r2]

Are the carbs filling with fuel?
What's the compression like?

[samt]

Yeah, carbs have fuel in. Compression is 110 to 115psi on all 4 cylinders.

I have the engine running now, but it wont rev over about 2000rpm