Merc 40 HP EFI No Power

[viper151]

I have a 2007 Mercury 40 Efi 4stroke . It will not get to plane and have a hard time getting 10mph out of it. It starts and idles smooth and when you put in neutral it will rev up but on the water it will not plane. It sure seems like a fuel problem. I have tried all the simple things like new fuel, fuel line and filter but the problem is still the same. Has anyone had problems with fuel pump, injectors etc or anything else that might cause this problem?

 

[alldodge]

Howdy

Sure wish there was an outboard guy here to help. Another guy with same engine but a 2011 model has the same issue.
http://forums.iboats.com/forum/engi...utboards/10028422-no-power-to-get-up-on-plane

Are you hearing any beeps before or after starting the motor?

 

[viper151]

My problem is now fixed but I had to bring it to a dealer to get it fixed. The problem was one of the ignition coils, the motor was actually only running on 2 cylinders. The way the motor started, idled and trolled I would have never suspected that. I was convinced that it was a fuel problem but apparently not. Hope this helps anyone else that might have a similar problem.

 

[alldodge]

Thanks, always good to know the outcome. Hope you hang around

 

[Hydrocephalic]

Reviving an old dead thread because I found it on Google and it pointed me in the right direction and maybe this will help someone else.

Same motor, same year, same problem. Boat wouldn't get up beyond about 3750-4000 RPM and topped out at about 10-15mph depending on number of people on boat. I tested fuel pressure and swapped the fuel filter with no change. The spark plugs looked fine but inline spark plug tester showed no power from the ignition coil for cylinder 1. Confirmed bad coil by plugging cylinder 2 power cable into the coil and again no spark even with swapping out spark plug cables. Got a new coil online and problem solved. I couldn't tell audibly that one cylinder wasn't firing.