Prop sounds like out of water

[newmexla]

All of a sudden we can only go very low speeds.<br />When try to give it more, prop sounds like it's out of the water, but boat doesn't go any faster.<br />Anybody know what this is all about? We did remove some fishing line, but this didn't help.<br />Also replaced all the oil in the lower unit and wasn't milky white and no evidence of water in unit.<br /><br />Thanks.

 

[imported_salty_dawg]

Re: Prop sounds like out of water

Your prop may have broken loose from the hub. What happens is the inner hub of the prop moves with the motor's prop shaft no matter how much gas you give it. When you're idling/slow speed, there's enough friction between the hub and the prop to turn the prop, but when you go past a certain point, the hub breaks loose and starts turning faster than the prop. RPMs & noise go up, but your boat slows down. You can get it fixed reasonably at a prop shop, depending on the size.

 

[newmexla]

Re: Prop sounds like out of water

Thanks for your quick response. Okay. So when we pull off prop, should be able to tell right away that it has broken loose from the hub? What will it look like? Sorry, very inexperienced and only one boat shop here. Just want to make sure we don't get raped when we take it in for repair.

 

[jim dozier]

Re: Prop sounds like out of water

Quick way is too take a permanent marker pen and make a mark from the outer propeller across the rubber sleeve to the inner hub and put it in the water and drive it in gear till it slips. If the marks don't line up the hub is shot. Alternately you can take it in to the prop rebuilder and they can put it in a vise and check pretty quickly. If your engine is running normally, and you can motor at idle speed but any attempt to speed up to planeing speed just revs the engine, and if you slow down to idle again and it grabs again its 99% certain you have a spun prop hub.

 

[imported_salty_dawg]

Re: Prop sounds like out of water

Depending on the size of the prop, if you have the boat where you can put it in gear(while not running) and manually try to turn the prop either with your hands or a broomstick, it might spin. If you have a big engine/prop combination this might be a little more difficult. If you have an aluminum prop be careful you don't force it & chip or break a blade. That's why I suggest something like a broomstick. Unless you're talking a 9.9hp or 15hp the broomstick will break or the prop will spin before you can do any damage. Good luck!