1983 Mercury 90 hp stalls under power only

[Logger]

Don?t know what to do I have a 1983 Mercury 90hp in line 6 cylinder that stalls when in gear under power only. I have changed all gas lines leading up to the motor thinking there was a pinhole in the line. Have changed the stater, plugs, diaphragm on the fuel pump, tried other power packs and have had no luck. I had two mechanics up North look at it and they are dumb founded. I am at my whit?s end the motor starts and goes into gear great with muffs on but when under power it stalls every time going in to gear forward or reverse. Have I missed anything that anyone can see. The only thing that comes to mind that I have missed is the Carburetors? (three of them) don?t know the last time they were cleaned and adjusted could this be the problem? Any suggestions would be greatly appreciated I am running out of time before I have to go up North with the wife and kids

 

[Chris1956]

Re: 1983 Mercury 90 hp stalls under power only

That is a classic symptom of the carbs being dirty or out of adjustment. Try opening the top carb idle mixture screw 1/8 turn. If it still stalls, open the mid carb 1/8 turn. Repeat with the bottom carb and repeat sequence if necessary. If you cannot cure it, you will need to rebuild the carbs (gaskets, inlet needle and seat and maybe floats).

 

[Logger]

Re: 1983 Mercury 90 hp stalls under power only

Thanks for the reply

I am going to try to adjust the carbs myself if not do you suggest I get three carb kits or just clean them ?

 

[Chris1956]

Re: 1983 Mercury 90 hp stalls under power only

At least get the gasket sets. They are inexpensive. Check the floats for cracking (hard plastic floats) or disintegration (foam floats) and replace if necessary.