overreving at 4000RPM

[man-of-war]

Hi guys,<br /> Finaly got to take the new to me Baja boat out for the first good and long get to know ya drive.The engine sound's strong,and responsive. I drove around at 3000rpm for about 45min stoping and takeing off geting to know the boat adjusting tabs,drive trim to get the best ride and max speed @ 3000ish RPM. With all the final adjustments made,took her up to 4000rpm and had it there for about 3min until going over a small wave this is where the engine started to loose speed and still stay at 4000rpm.<br />Looked at the coupler and it looks to be fine no grounded rubber or chunks not even a burning rubber smell.I then put the drive trim all down and the trim tabs all up and it took off fine, got to plane with out any assistance, got to 3000rpm ok 3500rpm ok 4000rpm ok for a min then loose speed and rpm stays at what ever rpm it was set at.There are no strangr noises coming from the drive. ANY THOUGHTS thanks

 

[man-of-war]

Re: overreving at 4000RPM

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[Boatin Bob]

Re: overreving at 4000RPM

Possibly the hub on the prop is starting to slip, do you have a spare prop or can you borrow one to test?

 

[Bondo]

Re: overreving at 4000RPM

I Agree with Bob,........ The Prop Hub is the next most logical place to Look......

 

[Don S]

Re: overreving at 4000RPM

I really don't think you have a prop hub problem, if it slipped, you would have dropped off plane and the rpms would have gone up to the rev limiter.<br />Did you try adjusting your trim?

 

[man-of-war]

Re: overreving at 4000RPM

Hi guys,And thanks for the replys.<br /><br />I got the prop off and don't know what I'm looking for. This is fresh from the propshaft this evening.<br /><br />DonS,YES I did try triming while it was losing speed, and before. Nothing will recover it when it's reving. The only thing that will work is pulling the throttle back to neutral, come to a stop then go again. Don't know if there are any tell-tail signs on those pictures/pieces that I post.<br /><br />Take a look at the coupler with the grease nipple, when I stick my finger back there to feel for the rubber, there's a metal plate that protects it.<br /><br />Look at the shaft and that O ring. What's that doing way out there? <br /><br /><br /> Aside from this, what/how is marine engine oil supposed to smell - like the oil from your car or a scented gas smell? I had some guys at the dock sniff the dip stick and they said that it smelled fine but I can smell a hint of gas. <br /><br /><br />

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