71 evinrude 85hp no start

[stupidbaker57]

I have an 85 4 cyl that had no spark, but after float testing the amp, I replaced it with an automotive coil and ballist resistor. Now I have spark, good cranking speed, clean carbs. The motor will crank for 10 or so seconds and then the motor will backfire out the exhaust once and go back into the cranking mode. I checked the timming by timming light while cranking and it looks like it's firing at 4 degrees before tdc. Even spraying starting fluid at it while cranking does nothing different.
Any ideas?

[boats.net]

Have you checked compression? Also when turning over the engine does it look like fuel is spitting out of the throat of the carburetor?