1983 25HP Will not start

I just bought a 14' boat with a 1982 or 1983 25HP Mercury. It has controls. I can not get it to start I have emptied the tank and put in new good fuel mixture and replaced the spark plugs. Both of these things were done before even trying to start it. The starter is dead, so I have been trying to start it by hand. The ONLY way it will start at all is if I remove the plugs and pour in a little fuel mixture. It will then run off that fuel. I did have a bad primer bulb, but replaced the whole hose and bulb. I checked the fuel screen at the pump and have removed the little plastic fuel canister. One thing i have noticed is if i push on the full fuel primer bulb fuel fills the canister and leaks out the top. Other than that I can find nothing else wrong. And yes I have checked the kill switch and it is in the run position. What else should I check on this ? Thanks.