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  1. #1

    Question Mercury 4 Stroke 60HP Bigfoot runs good at full throttle but not at max RPM and speed

    Hi, I'm a new boat owner and I've got a 60HP Bigfoot 4 Stroke EFI. It had been sitting covered up for the last 3 years and not ran any. I got it from a friend and the last time it was out 3 years ago it ran perfect. Back then it had just got brand new injectors and plugs. I actually got it running easily this past summer. But when we had it on the water when it was at full throttle it wouldn't get to max speed or RPM. It did reach max speed and RPM a few times and would run but once you throttled down and then throttled back up it wasn't max, Then at times it would all of a sudden catch up and go. I checked plugs even though they were new 3 years ago and they looked fine. I'm thinking it might be something to do with some old gas that might not have ran out. I have a brand new fuel filter I'm going to install once spring hits and we start getting it ready for the water. But if anyone could give me any information help that would be great. Thanks for all info in advance.

  2. #2
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    2,854

    Default Re: Mercury 4 Stroke 60HP Bigfoot runs good at full throttle but not at max RPM and speed

    Drain old fuel,drain and flush VST,clean pressure regulator and a bottle of Quickleen in fuel.
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  3. #3

    Default Re: Mercury 4 Stroke 60HP Bigfoot runs good at full throttle but not at max RPM and speed

    Quote Originally Posted by faztbullet View Post
    Drain old fuel,drain and flush VST,clean pressure regulator and a bottle of Quickleen in fuel.
    Thanks I will try that and get back to you.

  4. #4

    Default Re: Mercury 4 Stroke 60HP Bigfoot runs good at full throttle but not at max RPM and speed

    Quote Originally Posted by faztbullet View Post
    Drain old fuel,drain and flush VST,clean pressure regulator and a bottle of Quickleen in fuel.

    Did what you said and took the boat on Wednesday. It worked perfect. We got home a little late and I didn't cover the boat back up. It rained on it pretty good yesterday and now my motor tilt wants to stick in the up position. I can make the motor go back down with the trim on the throttle but from the motor it just makes it stop. I took out the trim up relay because it was making a popping sound. I wonder if it might have got a little water inside from the heavy rain? I knew I should've covered it because I work 24 hour shifts and just got back home today to mess with it. Any help would be greatly appreciated

  5. #5
    Join Date
    Apr 2016
    Location
    barnegat NJ
    Posts
    2,908

    Default Re: Mercury 4 Stroke 60HP Bigfoot runs good at full throttle but not at max RPM and speed

    I think I have seen this post on page 1

  6. #6

    Default Re: Mercury 4 Stroke 60HP Bigfoot runs good at full throttle but not at max RPM and speed

    Quote Originally Posted by johnnygjr View Post
    I think I have seen this post on page 1
    Yes sir, I created another thread with my new problem. I will try the hair dryer to dry the relay and fingers crossed that works. Cleaning my VST, draining old gas, cleaning pressure reg and quickleen worked great. I actually got a new fuel pump also. When I was trying to clean the screens on the pump they fell apart. Got a new pump for 30 bucks.

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