96 merc 150 stalls under load.

[chenson]

Usually if I replace my plugs my stalling problem goes away. this time it didn't help. It will die if any load is on the boat (driving on the trailer, floating my anchor, etc.) The motor has 900 hours on it. Any ideas?

 

[CharlieB]

Re: 96 merc 150 stalls under load.

What do the old plugs look like? Covered in carbon?

Is this a carbed or EFI motor?

Any carbs flooding?

 

[chenson]

Re: 96 merc 150 stalls under load.

It's a carbed motor. The plugs I took out were pretty black. The new plugs after running this past Sunday look ok. I'm not sure about the carbs. I plan on taking them off tomorrow and cleaning them.

 

[j_martin]

Re: 96 merc 150 stalls under load.

Have a gasket kit in hand for each one. Else you'll probably just make the problem worse. Often idle speed "rich" in the carbs is simple gasket failure internally. New gaskets, clean, and floats set right and you should be good to go.

While the carbs are off, check the bleed lines and check valves associated with them.

 

[SparkieBoat]

Re: 96 merc 150 stalls under load.

follow the instructions in my sig below

 

[chenson]

Re: 96 merc 150 stalls under load.

Thanks everyone. I've ordered some carb kits. They have never been off the motor. Good place to start.