2001 70hp 2 stroke wont rev past 3000rpms even in neutral

[Flatswalker]

hello this is my first post,i bought a 2001 yamaha 70hp with less than 80hrs on it but it wont rev past 3000rpms even in neutral.The things i did are Compression test 120psi all cylinders ,removed cleaned and replaced carbs,new fule element and water seperator,fule pump and prime bulb,checked all coils with multimeter for resistance and checked out good.this motor sat for 2 years i put it on my pontoon witch has an internal fule tank i removed and cleaned the tank but prime bulb does not get hard the fule does fill the fule filter and motor idles and revs fine with no miss and just stops at 3000rpms and will not go past. any help would be appreacited.

 

[99yam40]

Re: 2001 70hp 2 stroke wont rev past 3000rpms even in neutral

1st find out why primer bulb will not firm up.
You have a leak somewhere.

then Measure fuel pressure and vacuum to see what that shows.
Look under frequently asked questions for testing fuel system

 

[Flatswalker]

Re: 2001 70hp 2 stroke wont rev past 3000rpms even in neutral

1st find out why primer bulb will not firm up.
You have a leak somewhere.

then Measure fuel pressure and vacuum to see what that shows.
Look under frequently asked questions for testing fuel system

Thank you for help i will check out fule system faq's You mean vacuum before fule pump?

 

[99yam40]

Re: 2001 70hp 2 stroke wont rev past 3000rpms even in neutral

yes , what the pump pulls. You will see it in the thread

 

[Flatswalker]

Re: 2001 70hp 2 stroke wont rev past 3000rpms even in neutral

I borrowed a fule gauge from a friend and a portable gas tank to eliminate any problems in my internal tank for testing purpose. i did notice a blue wire with a plastic sleeve and bullet connector not connected to anything coming out of wire harness from ignition side not motor side but probably was never used,it also blows alot of smoke when trying to rev up?i will post results tomorrow.