1976 Evinrude 70 throttle/idle issues

[sportsmanphil]

I got stuck fixing a friends outboard.

Its an Evinrude 70 with 1976 on the timing sticker.

Once it warms up it runs like a raped ape. Problem is when you come back to throttle and it releases forward gear it idles way too high. I had to cut the motor off, crank it back up and before it idled up throw it in gear. I was afraid to push it in gear considering how high the idle is.

I pull the engine cover and find the throttle cam is not coming all the way back to idle, holding the carbs open. I can push the cam back a bit and the idle will drop. I assume the throttle cable is worn out.

There are some adjusting wheels on the throttle linkage but I could not get them to turn at the lake.

Any input, info or links on adjusting the throttle properly would be greatly appreciated.

 

[tashasdaddy]

Re: 1976 Evinrude 70 throttle/idle issues

disconnect cable, manually move linkage and see if it runs. did the timing plate also stick?

 

[sportsmanphil]

Re: 1976 Evinrude 70 throttle/idle issues

I will have to look at it again.

Let me try to give some better detail.

The throttle linkage is stiff but moves. The arm under the flywheel moves and seems fine.

The linkage that moves the large cam which moves the linkage for the 3 carbs seems to be the issue. Moving the throttle forward the cam moves which pushes the linkage for the 3 carbs. It will open the carbs to about 99% open.

The problem is when I pull the throttle back to N. The cam turns back allowing the carbs to start to shut but the throttle will hit N and the cam will stop leaving about 8% of the throttle at the cam (holding the carb linkage open. I had to by hand turn the throttle cam back allowing the carbs to shut for a normal idle.

 

[tashasdaddy]

Re: 1976 Evinrude 70 throttle/idle issues

sounds like bad cable. as i said disconnect cable, now holding the nub, that the cable connects to, advance the throttle, then return it to idle position, does everything move like it should? if it does, then the cable is bad, if not start trying to find what is sticking.