adjusting ide speed

[evinrude bayliner]

I have a 70s model 85 hp evinrude outboard. The motor runs great. I have found that i can get more power out of it by adjusting a screw on the side of the motor that allows the throttle to open upen up more. Before i take it out on the water I would like to know if this is ok. I tested the motor with the ear muffs on to give it water and it sounds and looks like it is reved up a bit more at wot. Will this harm the motor if I keep it at that setting or should I back off on that screw. I dont have a tachometer on the boat so I dont know what the rpms are. I dont want to damge the motor but I want to get all the power out of it the motor is capable of giving safely.

 

[R.Johnson]

Re: adjusting ide speed

You do most all engine adjustments With A sync, and link. You need a manual for this. Don't go near full throttle with that engine on a hose. You will be sweeping it up with a broom.

 

[F_R]

Re: adjusting ide speed

Sounds like you are adjusting the spark advance screw? Great way to destroy a powerhead by burning the pistons from preignition. And never run above fast idle on muffs. If you messed with the spark advance, you will need to use a timing light to put it back to specs.

 

[evinrude bayliner]

Re: adjusting ide speed

How do I know if it was the spark advance screw? The screw that I turned has a rubber stop on one end of it. It allows the bracket on the side of the motor that opens up the butterfly valve in the carbs. I can turn it back so they wont open up as much. I kept track of how many turns I rotated it.

 

[evinrude bayliner]

Re: adjusting ide speed

Looking on this forum it looks like I turned the throttle advance stop screw. Is this correct and will adjusting it hurt anything? Like I said i can turn it back the the former position.

 

[evinrude bayliner]

Re: adjusting ide speed

Here is the screw I turned.

 

[R.Johnson]

Re: adjusting ide speed

That is the spark advance screw, you will need a timing light to put it back.

 

[eli_lilly]

Re: adjusting ide speed

Here is the screw I turned.

There's at least two screws in that picture. The bottom one is the idle adjust, the top one (right under the flywheel) sets the max timing advance and if you turned that one you need to get a timing light and set it back properly or you will damage your motor.

-E

 

[F_R]

Re: adjusting ide speed

The one at the black arrow is the spark advance screw. Turning it was a bad. Has to be re-timed or you will damage motor.

 

[BoatBuoy]

Re: adjusting ide speed

I'm curious about who was holding that thing on the tailgate when you opened up the throttle. Must have been one Big Bubba.