1959 Evinrude 35hp Idle Adjust Screw???

[showngo2000]

I can't find much in the Seloc manual about what this screw does, and where/how to adjust it to the right place. I tried turning mine and it snapped...not a good sign. Any idea on how to adjust this? I'm having trouble getting it to idle low to a crawl without it dying.

Any place to buy another one?

Thanks!

 

[oldboat1]

That screw is a throttle stop. Idle issues are likely the result of a dirty or poorly adjusted carb (mixture needles). That's if compression (120, give or take) and spark (3/8 inch or so) are good. If it's in good shape, it will idle down pretty low and slow.

The screws are plastic and get distorted or brittle. A PO may have been using the screw to compensate for other issues, and tightened it down too much. They're available, but you might have to look around a bit.

What is the motor doing or not doing, and what work have you done on it? Is the motor new to you?

 

[showngo2000]

The motor runs good...high speeds, and low. Whenever I try to idle, it won't stay running after a minute or so..whether the engine is cold or warm. I can run the engine down to an idle, and it will kinda sputter around for a little bit, then finally die. When I start it up, it starts fine and will run, no problem. I've tried adjusting the carb needles, and it seemed to help, but I think it's still idling high.

Basically went through the entire engine in the past month:
Replaced and adjusted points and coils
Replaced spark plug wires and plugs
Replaced fuel lines and filter
Rebuilt carb
Among other small maintenance related things

 

[oldboat1]

Fuel ratio on the motor is 24:1 -- may do OK on a leaner ratio, but I would go with the original recommendation while working on it. Idle passages are up at the top of the carb, where the needle is located. It might be a good idea to start over -- about 3/4 out from lightly seated for the h.s. needle, and 1 to 1 1/2 open for the l.s. needle. Those are opening settings, and would adjust from there. Warm it up in a barrel or in the lake, then adjust in gear. I lean the mix until the motor pops or stalls, then back it out (about 1/4 turn richer for the idle needle).

[Edit. Actually, you might be close -- sounds like your mixture adjustment gave you high idle rpms (higher than seems right, anyway) -- would normally just throttle down at that point. Maybe that's about the time the throttle stop screw broke off, trying to back it out. But stalling out would indicate offhand that the air/fuel mix is a little too lean.]

 

[showngo2000]

For some reason I thought it was 50:1, I've been running it there. . I'll mix it to 24:1 and try tweaking the needles again. What effect (if any) would a 50:1 mix do as oppose to a 24:1? Could that simply be my problem?!?

 

[oldboat1]

I think it could make the difference if you are close. Let it warm up on the 24:1 before adjustments -- see if you still get the stalling at idle.

 

[showngo2000]

Well, put it in the water with a 24:1 (-ish) mix. And the sucker idled perfect. Wouldn't you know?!? Thanks oldboat for the help.

 

[oldboat1]

Glad you got it handled, showngo. It sounds like you have it in good shape -- Happy boating!