77 Evinrude 140 HP Low Idle

[Bdt 1967]

My Evinrude will not idle correctly upon start up or after sitting for a while, the engine will try to die every time that I attempt to put it in gear, after i run the engine for about 5 min at anything over 2000 rpm it runs great, I can go from neutral to forward and neutral to reverse, but after i shut the engine off and sit for a little bit it has the same problems all over again it tries to dies and wont start up right away. In an attempt to fix the problem I

-Rebuilt carburetors
-New sparkplugs
-New gastank
-New fuel lines from tank to carbs
-New fuel fittings
-New fuel tank pickup
-New primer bulb
-Seafoam
-Good compression
All this did not fix the engines idle. I then noticed a leak from my fuel pump, about 1 drop every second when its not running. I rebuilt the fuel pump and now i have no leaks. I have not tested the engine but when i take it to the lake this weekend if I still have the same problem do you guys have any suggestions as to how to fix it? I dont think its timing because the boat runs great when its been running for a little while. Any help will be appreciated, It idles around 700 rpm.

 

[tashasdaddy]

Re: 77 Evinrude 140 HP Low Idle

is idle in neutral or in gear, is idle in the water or on muffs?

 

[Bdt 1967]

Re: 77 Evinrude 140 HP Low Idle

In water, in neutral. I have thought many times about turning up the low idle, but for the life of me I can not find the low idle screw, I don't have a manual, even tho I need one, I would like to get this fixed before the weekend. If anybody has one of these engines could you point out where the low idle screw is.

 

[Bdt 1967]

Re: 77 Evinrude 140 HP Low Idle

I did a search on this site and found this a thread, will my engine have a similar setup? In the thread it said the top screw in the picture is the idle stop screw.

 

[iwombat]

Re: 77 Evinrude 140 HP Low Idle

Took me awhile to dig one up, but this should match your motor.

 

[Bdt 1967]

Re: 77 Evinrude 140 HP Low Idle

Yep thats what it looks like, I screw it in to bring the idle up right? Thanks for the help, this site is a treasure trove of information!

 

[iwombat]

Re: 77 Evinrude 140 HP Low Idle

You got it right.


Play through.

 

[Bdt 1967]

Re: 77 Evinrude 140 HP Low Idle

How high should it idle in neutral in water? I know it should be around 750 in gear.

 

[HighTrim]

Re: 77 Evinrude 140 HP Low Idle

Set it to 750 RPM under load in gear. Check to see if the timer base (starboard side, under the edge of the flywheel, linked to the throttle lever) moves smoothly without sticking when you advance the throttle.

Take the airbox cover off & observe whether the throttle plates are parallel.

Also, the timer base should start it's travel before the throttle plates start to open, or else the old girl will die when you give her the throttle.

Also, how well were the carbs rebuilt? Did you pay special attention to the jets/orifices? Remove them and thoroughally clean them?

 

[tashasdaddy]

Re: 77 Evinrude 140 HP Low Idle

idle has to be set in the water, and in gear. iwombats pic is correct. my pic is of an 1988