Buddy is having problems with his older envirude engine revving up on its own

[gunner76]

Buddy has a '93 40 horse Evinrude and is having problems with the motor revving up to 5-6000 rpms on it's own and he can't figure it out.

He said when it revs up the throttle plates are not opening up and if he turns the electric choke on it idles back down. Also he said when it revs up the the primer ball on the gas tank goes limp. He's tried a new tank and fuel line and made sure all fuel and vacuum fittings are tight.

 

[gunner76]

He got it figured out. He took the advice I got from another source and it ended up being worn throttle blade shaft where it goes through the Venturi.