Boat reving but wont go fast enough to plane

[rasnattydred]

Hello all,
Was at the lake today and was just cruising around slowly for a while and when I finally went to plane and go fast, the boat would not go fast enough to plane and then I got a huge rev from the engine, this happened several times, the boat started fine and ran fine ar low speed.
Any advice?

 

[dubs283]

Re: Boat reving but wont go fast enough to plane

spun prop hub

 

[Don S]

Re: Boat reving but wont go fast enough to plane

Try a different prop. Sounds like a spun hub.
But without knowing what you have, who knows for sure. You may not even have a prop with a hub.

 

[futz]

Re: Boat reving but wont go fast enough to plane

nice to know what make, hp, and year of drive and motor.

But yea put your spare prop on.

Don't have one? Well you should.

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

Sorry about that, it is a 1997 Mercruiser Alpha one 4.3L V6 I/O.
I am hoping it is the prop, we didn't smell rubber or anything so hoping it is not the coupler.

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

spun prop hub

Is there anyway I can test if it is a spun prop?
How hard is it to take the prop off and put the spare on?

 

[WizeOne]

Re: Boat reving but wont go fast enough to plane

Is there anyway I can test if it is a spun prop?
How hard is it to take the prop off and put the spare on?

Get one of those yellow grease markers like they use at tire shops and mark across the outer prop casing and the inner spline. If it is spinning, that mark will break apart as the outer casing spins.

It's easy enough to change the prop. A cotter key, sometimes a tab washer and a big old nut. It should not be tight. Make sure you grease the splines before you leave your next prop on.

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

Get one of those yellow grease markers like they use at tire shops and mark across the outer prop casing and the inner spline. If it is spinning, that mark will break apart as the outer casing spins.

It's easy enough to change the prop. A cotter key, sometimes a tab washer and a big old nut. It should not be tight. Make sure you grease the splines before you leave your next prop on.

I got the prop off, then there is the hub. I can pull that off etc. no way to tell by looking at it? the spines are not worn down or anything.

 

[TowRoper]

Re: Boat reving but wont go fast enough to plane

hiya, the prop came off the prop hub?

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

hiya, the prop came off the prop hub?

YEs the prop comes off, then there is a brass piece in a rubber casing (I assume this is the hub?) that slips onto the spined propeller shaft.

 

[futz]

Re: Boat reving but wont go fast enough to plane

can you take a picture and post the offending prop? I know for a fact there are prop shops near you, and / or west marine, merc dealers. You can bring it in to them and match up the prop pitch. probably a 15 spline.

 

[Don S]

Re: Boat reving but wont go fast enough to plane

Being as you have a 97 Alpha, you may have the Flo Torq hub. Does it look like this.

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

Being as you have a 97 Alpha, you may have the Flo Torq hub. Does it look like this.

Yup, that looks just like it. The big rubber part seems to be worn on the outside, and signs that the rubber part is slipping on the inside of the prop itself also. Could this be my problem and if so what is the nam eof that part and where could i get anew one?
Thanks for the advice and help!

 

[Kettler]

Re: Boat reving but wont go fast enough to plane

Yup spun prop.

Same thing happened to me scared the &#%%$@ of me. Limped back home and installed new prop and off we went.

Good Luck

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

Yup spun prop.

Same thing happened to me scared the &#%%$@ of me. Limped back home and installed new prop and off we went.

Good Luck

Yeh it sounds like it, it looks like something I can do myself, but i read on another forum that I should take it to a prop shop (not even sure they have those). Any advice on that?
I already ordered a new hub kit. I assume I don't need a new prop as the hub is not connected to the prop.

 

[QC]

Re: Boat reving but wont go fast enough to plane

With other style hubs, prop shop. With the FloTorq system, if the plastic insert has failed, and all else is good, very easy to do yourself. The question ultimately is, what caused the hub to blow?

 

[rasnattydred]

Re: Boat reving but wont go fast enough to plane

With other style hubs, prop shop. With the FloTorq system, if the plastic insert has failed, and all else is good, very easy to do yourself. The question ultimately is, what caused the hub to blow?

Well it seems like I may have hit the prop because there is what looks like muddy scraping on the part of the stern drive that is below the prop, I do not know the terminology for it. We did pick up people from a very low dock where it could of happened. The muddy scraping tells me either way that we did touch bottom so prob not a coincidence.

 

[QC]

Re: Boat reving but wont go fast enough to plane

Well it seems like I may have hit the prop

That would explain it.

the stern drive that is below the prop

Skeg . . .