Mercruiser 2.5 shuts spits, sputters, and dies after 20 - 30 minutes

bunky2004

Cadet
Joined
May 22, 2016
Messages
29
ok so just as the title says, after 20 to 30 min she starts getting real sluggish and eventually (45 to 50 seconds) dies. Also, it struggles on quick acceleration and seems to take a while to start and stay running(five or six times before it idles well at initial start when engine is cold. After it dies, it will not restart until 30 or so minutes has passed. Here's what i have done so far. New plugs, wires, cap, rotor, and coil. It has a rochester 2gc carb it. I have removed the filter and cleaned it to the point of damn-near-new lol. Also, i took the carb off and cleaned it as well as installed new gaskets. Problem still remains. Any suggestions?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,927
Sounds like a plugged fuel vent. Next time it starts to caugh and die, open the fuel cap. Of you hear in rushing air, your fuel vent is plugged
 

bunky2004

Cadet
Joined
May 22, 2016
Messages
29
alright, so another update. As it turned out, i was lucky and have a clear vent. Somehow though my distributor was off by one tooth. funny thing is, now that its in time (8 btdc) it seems to run really rich (i think) when i run it on the muffs, the puddle under the boat has fuel in it and the exhaust burns the eyes. Since I just rebuild the carb, do you think I need to re-adjust the mixture screws? Also, it now runs like a top but after you shut it down when warmed up, it almost seems like it floods out and wont start
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,259
do you think I need to re-adjust the mixture screws?

Ayuh,.... Sounds more like the floats are set to high, or the carb is leakin', internally,.....
 
Top