1984 evinrude 70hp

[smitdog]

I have a 84 70hp evinrude . I recentaly replaced head gasket, spark plugs , and one coil . the boat runs decent and low rpms but when I give it full throttle it falls on its face . When I decrease the throttle it comes back . I have checked the compression and I have 115 lbs across the board . I have also checked the fuel pump and fuel lines and all seems good . where should I go next . Thanks

 

[Joe Reeves]

Re: 1984 evinrude 70hp

Either the carburetors are fouled (running lean), the timer base under the flywheel is sticking (retarded spark), or the throttle butterflies are opening before the scribe mark on the cam aligns dead center with the throttle cam roller.

 

[smitdog]

Re: 1984 evinrude 70hp

Thank yo Mr. reeves I am going to clean the carbs tonight . I do have a question about you post . You talked about the timer base under the flywheel, do you mean the one that has the linkage going to it off of the throttle linkage? or is tis piece under the flywheel out of sight?

 

[tashasdaddy]

Re: 1984 evinrude 70hp

the one you can see, it is a plate that turns when you move the throttle linkage, it advances the timing. if not moving smoothly effects the running.

 

[smitdog]

Re: 1984 evinrude 70hp

I dissassembled all three carbs , soaked them in GUNK CARB DIP and reassemabled . The boat runs better than it ever has , Thanks guys