Will not start and shudders between starting attempts

I have gas, spark and air, not running and it will shudder in between starting attempts. Also, white smoke will come out the air breather. It will not start now at all.
I replaced the fuel pump and purged air from lines truck ran for a day and ran a little rich according to smell. I have replaced the ignition coil and took plugs out of cleaned them and each plug has white spark and is getting through the plug. Compression seems fair (I have no tester for that) but it blows by and shoots the gas out quickly. When I run the starter it will try to fire and when you let off the starter it rolls back and shudders and white smoke billows out the air intake. Could this be a timing issue?