Help!! I Need Speed!!

[Dan Legg]

Hey all,
I have a 1981 50 HP Merc outboard. It starts and runs great, but underload will not go to high speed, it only idles up and down the river. The motor revs really high but just won't go very fast. I have changed the prop. Was told that possibly the throttle cable was stretched. I have pushed the throttle back by hand but couldn't get any more out of the motor. Does anyone have any ideas on what the problem might be?? Any help would be great !
Thanks in advance.
Dan

 

[corm]

Re: Help!! I Need Speed!!

Hi,
Can you post a picture of the boat transom & engine out of the water?

 

[xxturbowesxx]

Re: Help!! I Need Speed!!

We need more info what size and type of boat we are talking about first off. To me it sounds like you are running on half the cyl or you need to clean your carbs.

 

[Arkman]

Re: Help!! I Need Speed!!

I had a similar issue on mine. I was only running on 1 cylinder. You could test to see if you have spark. It was fairly easy to test (at least in my case) and gives you a good idea if you have an issue there. After I fixed that issue I could go full throttle but only 5 mph and in that case the carb just needed adjusting (I had already cleaned it several times)

Now runs like a champ.