1994 Mercury 175 XRI EFI, Loss of Power under Load

[WarrenJr]

I have a 1994 Mercury 175 XRI EFI. In a barrel the motor runs great with great throttle response. Take it out in the spillway and engine bogs down. It would not turn over 1200 rpm. The boat sat up for approx. 2 years. The fuel in it is fresh. I went throught the fuel system, did not find any gum buildup. Could someone please guide me in the right direction. I am leaning toward an electrical problem.

 

[CharlieB]

Re: 1994 Mercury 175 XRI EFI, Loss of Power under Load

Any more than an idle will empty a barrel in about a heartbeat.

The barrel is great for setting idle mixtures and idle speed, however, carbed motors with adjustable idle mixtures MUST BE set RICHER than best idle speed in Forward gear to provide the additional fuel necessary for acceleration.

Too lean an idle and large application of throttle the motor coughs and dies.
Back out the idle mix screws an 1/8 turn and retest. Ideally, make adjustments in even smaller incremental turns until on a full WOT from idle there is NO hesitation in the slightest.

 

[CharlieB]

Re: 1994 Mercury 175 XRI EFI, Loss of Power under Load

I am assuming that you did totally clean the carbs, no gum in the float bowls is not a guarantee that the idle fuel and air passages are also perfectly clean.