Evinrude shifting into neutral at WOT??

[combat]

I finally was able to get my motor water ready and we took it out on a small lake last night to test everything and when going WOT the motor would suddenly rev really high and I had to turn the throttle back like it was in neutral...

Is this a common problem or something that sounds like can be fixed easily?

 

[samo_ott]

Re: Evinrude shifting into neutral at WOT??

What model/engine is it? It sounds like you clutch dog it letting go and dropping it into neutral.

 

[combat]

Re: Evinrude shifting into neutral at WOT??

What model/engine is it? It sounds like you clutch dog it letting go and dropping it into neutral.

1975 Evinrude model # 25553B

What causes it to slip like that? Maybe I didn't get it put all back together just perfect? I did have it apart but I guess it did it before taking it apart too...

 

[F_R]

Re: Evinrude shifting into neutral at WOT??

There are three possibilities:

1: It actually is kicking out of gear. Does it make any grinding noises or make the shift lever jump?

2: Your prop hub may be slipping. That will be a smooth slip, like spinning your wheels on the ice. Will ususally hold up to a certain throttle, then slip.

3: It may be cavitation (ventilation). That is where a big air bubble forms around the prop. Caused by weeds, improper installation (too high) or tilt, something causing air bubbles around the prop, etc.

 

[combat]

Re: Evinrude shifting into neutral at WOT??

It's a smooth slip for sure...the shift lever never moves. It's perfectly normal during half throttle and eve works somewhat during WOT but it always eventually slips and revs really high and I have to shut it down and restart it to get it working right

 

[samo_ott]

Re: Evinrude shifting into neutral at WOT??

Then it sounds like #2. The prop is slipping. If you want to verify it, remove the prop, draw a line on the hub and prop on the inside. Re install and run it again until it happens. remove prop and see if the lines have moved. If yes, a local OMC dealer can re hub the prop for you or buy a new or used one to fix it.

 

[combat]

Re: Evinrude shifting into neutral at WOT??

Then it sounds like #2. The prop is slipping. If you want to verify it, remove the prop, draw a line on the hub and prop on the inside. Re install and run it again until it happens. remove prop and see if the lines have moved. If yes, a local OMC dealer can re hub the prop for you or buy a new or used one to fix it.

Thanks I will try this and see what happens.....is it harmful to run it like this as long as I shut it down when it does the high rev?

 

[wilde1j]

Re: Evinrude shifting into neutral at WOT??

No, but it will get worse to the point of unusable.

 

[combat]

Re: Evinrude shifting into neutral at WOT??

I was also going to ask...when I reinstalled the prop form when I had it off, I didn't tighten down the hub nut as much as I think it could have been because it didn't look like the holes on it would line up with the ones on the shaft and that I wouldn't be able to get the cotter pin in...should I try and tighten down as much as I can and see how the holes line up?

 

[F_R]

Re: Evinrude shifting into neutral at WOT??

Won't help

 

[samo_ott]

Re: Evinrude shifting into neutral at WOT??

And yes, you can use it as is but back off when it slips. And it will get worse slowly. It wont fix itself.

 

[egodwin3]

Re: Evinrude shifting into neutral at WOT??

And yes, you can use it as is but back off when it slips. And it will get worse slowly. It wont fix itself.

I also have a 1962 sportwin 10hp and its doing the same thing. I found a local guy with all the parts for it but we replaced the prop with a working hub and I put a new upper/lower link in and its still rev up after a certain speed. There is no thump or anything like hitting something it just rev up. I have no idea what would be wrong with it at this point. Is there anything else that it could possibly be

 

[Outsider]

Re: Evinrude shifting into neutral at WOT??

Check your engine height. The flat plate on the lower unit should be barely out of the water when at WOT. If it's too high, you could be ventilating (grabbing air) ...