1998 Mercury 150 Saltwater Series Starting Prob When Warm

[howieha]

My engine always starts right up when the motor is cold but after I have been running and turn the engine off it won't start right away. I have to give it a lot of throttle and crank it quite a bit for it too start. It also stalls out at idle speed in forward and reverse when the engine is warm.

The troubling part is it doesn't happent all the time. Any ideas.

Thanks

 

[cz0164]

Re: 1998 Mercury 150 Saltwater Series Starting Prob When Warm

Got the same problem with my 2003 2 stroke carb. Did you have any luck in finding the problem?

 

[hkeiner]

Re: 1998 Mercury 150 Saltwater Series Starting Prob When Warm

You do have to have the throttle a little forward when starting the motor when it is warm. This opens up the throttle plate a little thus allowing more air to enter the cylinders when cranking. If you have the throttle in the center position, the throttle plate is fully closed causing the motor to more easily flood when cranking. Having said this, if you still have a problem starting/idling with the throttle a bit forward, you may need to clean the carbs. If the low speed idle air passages are gummed up, you will have a too rich of fuel/air mix going to the cylinders when cranking and idling. The overly rich mix helps when starting a cold motor, but not when it is warm. This is what I discovered after I got my 1996 150HP outboard and had the same starting problems when the motor was warm. I cleaned the carbs and keep the throttle a little forward when cranking, and my starting problem went away.

There are many other possible causes of starting problems when the motor is warm, such as leaky enrichener valve or incorrectly adjusted carb floats. Also, your should check for proper spark on all cylinders when the motor will not start. Just some thouights...