Evinrude 150 V6 losing power

[Law]

I have a 17.5 foot Hydra Sport Bass boat with a Evinrude 150 V6 and the boat planes out quick and the former owner said that the boat would run 71 mph. I noticed that when I try to reach top speed and about 5000 rpm the motor feels like it loses power like its a fuel problem. The motor manual said that the motor is rated at 5500 rpm. The motor runs great at 4000 rpm and speed of 52 mph but any faster the motor cuts out. Can anyone help me out on this problem or any ideas how to fix it. Thanks

 

[Sir Robin]

Re: Evinrude 150 V6 losing power

Sounds like fuel delivery problem. Hook up a remote tank and see if it runs better. Anti syphon valve will stick........ I took mine out

 

[Law]

Re: Evinrude 150 V6 losing power

what is the anti syphon valve and could it be spark plugs. I checked the fuel filter today and it had some dirt in it and i cleaned it out I have not tried it to see if that may be the problem. I dont think its something serious just something minor but hard to find.

 

[emdsapmgr]

Re: Evinrude 150 V6 losing power

Helps to know the year of the engine. Is this a carb engine or fuel injected? 90 degree or 60 degree looper?

 

[Law]

Re: Evinrude 150 V6 losing power

Its a 1997 evinrude v6 it has six carbs to it I do not think its fuel injected. The gaskets on the carbs looks good.

 

[Sir Robin]

Re: Evinrude 150 V6 losing power

The fitting on top of the tank has a check ball in it that gets dirty and only partialy flows. Many posts about it here. Could be plugs, but symptoms you describe suggest fuel delivery. If all components of carb/vapor seperator/vro /choke solonoid are dry, as in no leaking, I would look at the tank and fitting. These are thirsty motors, as can be seen by the size of the fuel hose 3/8" , They will use it all at WOT as i am sure you know. See if the bulb goes flat at WOT. If it does, clear the anti syphon valve.

 

[Law]

Re: Evinrude 150 V6 losing power

What brand of spark plug should I use with this engine