TOPIC: throttle question

I tried my motor on the water for the first time today. It seems when I have it set as fast as it can go (or full throttle) It basically sounds just like a high idle and the boat doesn't go very fast , safe to say my 6hp motor was pretty much the same but this ones 18hp.

My old 60's johnson 40hp had the exact same problem , but I remedied it by just reshifting into drive and it solved it. It would instantly rev much higher and take off. However doesn't work with this evinrude 18hp. It idles and shifts fine , just doesn't sound like it revs very high and won't go very fast.

e: Just by reading your commments, I would verify at the ramp or driveway that both cylinders are firing .! Had a bad COIL before on a 18hp Merc & it was screaming in the test water bucket, when I pulled one of the plug wires OFF, engine stopped.
.. Restarted & then pulled the other plug wire off & NO effect ,or loss of rpms, as that was the cyl not getting hot spark .!
.. Sounds like you only have ONE carb on that engine.? so should not be fuel issue.
.. If electrical , could just be dirty ,/ pitted points .

I agree with Split. Easiest way to do this is to pull your plugs and then install them in their wires and lay them agaist the motor block to ground them. Give the pull cord a yank and watch the plug gap. If you don't see spark on both plugs you're only hitting on one cylinder, which is what it sounds like.

Both cylinders are getting spark. It just seems like it's not reving as high as it could. I heard that part of a motor accelerating is not only opening the carb but also speeding up the timing? Maybe the timing is speeding up?

That's mostly what It feels like , like it's on the highest no wake speed it can go before actually going fast.

Don't waste your time laying a plug on the block to check for " good " spark!

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Put a timing light on this thing and verify that you have good spark at idle to full throttle on both cylinders. There are timing marks on the magplate and flywheel that can be checked as well.

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Broken / open reed valve will also mean that motor runs on one cylinder.

Ok , I figured it out. There's a knob on the motor that says "high speed adjust" , I just had to turn it higher. You guys had me worried there about the one cylinder thing.

Glad you got it figured out and it wasn't something more serious, emosun.

Glad you figured it out too. I use the plugs against the block test as a go-no go test. Quick and easy.

Glad you got it figured out. But there is one thing to check too. Look in the throat of the carb and make sure the butterfly is open all the way at full throttle. If not adjust acordingly.
Mike aka pathfinderz1