[kirk12]

I was on my way to the ocean today. I was cruising along at 4200rpms doing 27mph. Then my engine jumped to 5000rpms and my speed drop to 20mph. I thought I sucked in some seaweed. I stopped the boat put it in reverse and I thought that my problem was over. Well it lasted the entire time while I was out. It would run perfect for 10 minutes then the revving would start. 30 seconds later it would be fine...and so on and so on.

It sounded as if my boat was changing gears

Any ideas of what it may be?

 

[gverb1219]

Sounds like you spun the prop

The vulcanized rubber between the prop shaft and prop most likely seperated. At lower RPM's it will seem ok, but at speed, the load on the prop is too much and it will slip.............feeling like it's going into nuetral and back.

You can have the prop reconditioned for about $80 bucks.

Check a local marina, they can let you know who in your area does it. Or maybe someone will chime in and refer a local prop guy for you.

Thats why you should always carry a spare prop............

A spun hub inside of the propeller.

Sometimes the hub will slip inside of the propeller at higher rpm's. The quickest way to check a bad hub is to try another propeller to see if it slips at the same rpm's or you can try putting a dab of paint on the hub and a dab on the prop and try it to see if the 2 marks still lineup after a trial run. If the hub has spun, you will have to take it to a prop shop for a hub replacement. This can cost between $50.00 to $75.00 and some prop shops will not guarantee the new hub to hold.

This post edited by gverb1219 09:12 PM 08/03/2008

 

[MakoMike]

gverb1219 wrote:
Sounds like you spun the prop

The vulcanized rubber between the prop shaft and prop most likely seperated. At lower RPM's it will seem ok, but at speed, the load on the prop is too much and it will slip.............feeling like it's going into nuetral and back.

You can have the prop reconditioned for about $80 bucks.

Check a local marina, they can let you know who in your area does it. Or maybe someone will chime in and refer a local prop guy for you.

Thats why you should always carry a spare prop............

A spun hub inside of the propeller.

Sometimes the hub will slip inside of the propeller at higher rpm's. The quickest way to check a bad hub is to try another propeller to see if it slips at the same rpm's or you can try putting a dab of paint on the hub and a dab on the prop and try it to see if the 2 marks still lineup after a trial run. If the hub has spun, you will have to take it to a prop shop for a hub replacement. This can cost between $50.00 to $75.00 and some prop shops will not guarantee the new hub to hold.

I'll second that diagnosis.

 

[boloranks]

wow here is a tip, if your boat is in the water, raise the drive up use something and make a mark on the prop and the hub. take it for a ride come bck and take a look to see if the mark u make is still line up, if it is its not your prop, if its not line up then it is your prop hub slipping.