Engine Revs up but doesn't speed up

Jhohman5

Cadet
Joined
Jun 4, 2015
Messages
6
Hi everyone,

I have a 1990 40hp Evinrude VRO w/ VRO deleted. I was driving around had had the boat almost WOT and the engine was doing fine. I stopped and and went to take off again and when I went to give it some more throttle the engine reved up but I was not speeding up. I was able to keep moving forward if I stayed under 2500 RPMs. I thought for sure I spun the prop and it was the end of season so I was not too worried about it. Here I am this past weekend dewinterizing, put a new prop on. 12.5X13 is what it called for. Took out went down the river just fine and got to the big lake to go WOT and I am getting the same symptoms. If I stay under 3000RPMs I can move forward fine but anytime I go to accelerate nothing happens and only the engine revs up. I talked to a mechanic and he said it was a prop but I just put a band new one on. I understand there is a slight chance that I could have received a bad prop but....I'm not going to hold my breath on that chance. Reverse works great also not sure if that would make a difference or not. I am trimmed down all the way too. I haven't made any height adjustment to it ever so I know I'm in the water all the way where it should be. Any other ideas out there of why this would be happening? Thanks in advance for your time and suggestions
 
Last edited:

Tim Frank

Vice Admiral
Joined
Jul 29, 2008
Messages
5,346
The test for a spun hub is extremely simple and dead-nuts accurate.
Did you actually test the original before spending $100- + for a new one?
If not, do a forum search fro "spun hub" and read the test procedure so that you can rule it out as a cause.

Seems like you were "sure" it was a spun hub without testing....and now you are "sure" it is not....also without testing.
That is expensive sport and not real troubleshooting. :)

At this point, I would agree that the odds of a brand new defective prop are slim, but not zero....and if you are going to try and return the new prop you should verify whether or not it IS defective.

Read Racerone's post above....another dead simple check....and the clear step 1 now.
 
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