1985 Mercury O\B will not start

martinm54

Recruit
Joined
Mar 13, 2012
Messages
4
I just upgraded the engine on my pontoon to a larger motor. It is a 1985 Mercury 75hp. I had the boat out on the water about 10 days ago and started and ran fine. The only issue I had was the pitch of the prop need to be changed. So this week I put a new prop on and took boat back to lake for test run. After backing boat back into water attempted to start engine but could not get it to start. It would cranking fine and it did start but then spudder and died. I did notice then when I tried to pump the primer ball it would never fill up and never got hard. Was wondering if it could be a issue with the gas link or the valve in the primer ball and one thing I have not checked yet would be the fuel line connection to the boat.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,552
Re: 1985 Mercury O\B will not start

Could be a bad fuelpump diaghram. Did you see fuel in the water?
 

martinm54

Recruit
Joined
Mar 13, 2012
Messages
4
Re: 1985 Mercury O\B will not start

I tried starting it again after letting it sit for a couple of hours with the same results. I didnt think to check the water to see if it had any fuel floating on the water.
 

aussieflash

Lieutenant Junior Grade
Joined
Feb 5, 2011
Messages
1,004
Re: 1985 Mercury O\B will not start

Take off cowl and get helper to pump ball again and look for fuel leaks from lines or carbs.
Are you using correct starting procedure,does that motor have enrichener or choke?
 
Top