2.5 switch over to 3l ?

[ofna2005]

Guys I want to drop my 2.5 Carb motor for a 300promax . Do I have to change the jackplate also? And my boat has a pressure put set to 5lbs of pressure is that to much for the 3l ? I was told the motor had its own pump on it so can I use boot of them ? Thanks

[activator22]

Depends on what jackplate you have. Some are not rated for the heavier 3.0 motors, some are... Not a big deal in smooth water, but I'm guessing you running in some bumpy stuff.

The 5lb pump you are talking about sounds like a fuel pump - I believe the promax has it's own internal pump, you can either keep the external pump as a primer or get rid of it, and either add a hand squeeze primer bulb or just rely on the internal pump to pull the fuel up from the tank when starting. I went from a similar setup (2.4 carb with 5lb pump) and switched to a hand bulb, but after two seasons, the difference in cranking is about 2 seconds using or not using the bulb after a few days of sitting..

[ofna2005]

I have Bobs machine shop jackplate on the boat right now . And yes I was talking about the fuel pump . That great I will leave it in there for now . Thanks for the help .

[ofna2005]

Okay motor has been installed only thing left is the trimp pump . Which leads me to my next question . The boat has a full tank of premix right now Amsoile Dominator at 42/1 do I have to throw it away or can I use premix oil in this motor also?