Trying to smooth out a 93 evinrude 40hp. unhooked the vro oil system, engine will crank up very easy, but will act like its running out of gas. When i push the choke in, it cleans up for just a minute then back to dying out again. I can stand there and push the choke in everytime it does it, and will run all day. Does anyone have any suggestions as to where to start?