40Hp Merc. Lacking power

Hey there, New poster here.

I have a Qunntrex Hornet Trophy 435 that has a 2006 ( i Think) 40Hp Mercury 4 stroke EFI outboard bolted on the back, Anyway long story short I used it everynow and then on the coast and pretty happy with the power output. It sat around for a few years now. Just yesterday I took it out on an inland lake. And it really feelt slow and sluggish

As for weight, There was 3 of us, 250kgs worth. 45 Liters of fuel, an esky and a light breeze . It took so long to get up on a plane, full Throttle took maybe 2 minutes to get up. once it was up went okay.

Am I just expecting to much from the motor. I always Thought it had more go than that when i used to take it out on the coast.

Any ideas?

Re: 40Hp Merc. Lacking power

shark93 said:

?...... It sat around for a few years now.......

Click to expand...

Think there in lies the problem!

Check your fuel tank and filters for water content. You're probably running on water diluted fuel. :joyous:

Re: 40Hp Merc. Lacking power

I changed The Fuel, However not the filter. Could that be it?

Re: 40Hp Merc. Lacking power

By "changed the fuel", does that mean you drained and renewed your fuel or simply filled the tank with fresh fuel?

Either way, I would draw a sample of fuel from the tank into a clear container. Allow the fuel to settle for at least a couple of hours. Any water content will settle to the bottom of the container and will be quite apparent.

Not knowing your set up, check any and all filters (a water/fuel separator is highly advised).

Should you discover water in either and/or the filters, you will hae to run the engine under load for several minutes to purge the injection system.

Re: 40Hp Merc. Lacking power

If fresh fuel now on board, change fuel filters and see what happens. How's the engine trim working ...OK ?