Prop slipping?

[Wick77]

I have a late 80s 9.9 merc. As I travel whether full throt or not at times it feels like there is a clutch slipping? I understand there is no clutch but that's what it feels like when traveling. Just like a clutch slipping in a car. Engine revs but can feel loss of thrust in water. I have no idea? Fairly new to boating. It's pushing a 14' Jon boat. Anyone have any idea's? I pulled propeller off and everything seems right. Thanks!

 

[CharlieB]

Re: Prop slipping?

While you have the prop off, draw a line across the hub, from the outside barrel across the center splined hub. Run the motor again make it feel like it slipped. remove the prop and see if your line is still straight. If not then the center hub slips the rubber cushion between the two parts. A prop shop can push that hub out and push a new one in. Call for an estimate and compare to a new prop.

 

[Wick77]

Re: Prop slipping?

While you have the prop off, draw a line across the hub, from the outside barrel across the center splined hub. Run the motor again make it feel like it slipped. remove the prop and see if your line is still straight. If not then the center hub slips the rubber cushion between the two parts. A prop shop can push that hub out and push a new one in. Call for an estimate and compare to a new prop.

I never would have thought of that! So simple! Thank you I will try and get back to you. Not as costly as I thought it may be. Lets hope!

 

[Whitey1974]

Re: Prop slipping?

I'm getting ready to order a new prop for my late 80's 9.9 that has the same problem. The local shop wants $40 bucks to replace the rubber hub. Iboats has brand new Solas Amita props on sale right now for $49.49. Comes to $55 after shipping. Buy a new one and if your old prop is in good shape get the hub replaced and keep it for a backup.

 

[Wick77]

Re: Prop slipping?

I'm getting ready to order a new prop for my late 80's 9.9 that has the same problem. The local shop wants $40 bucks to replace the rubber hub. Iboats has brand new Solas Amita props on sale right now for $49.49. Comes to $55 after shipping. Buy a new one and if your old prop is in good shape get the hub replaced and keep it for a backup.

Ok, don't have a manual for my Merc. How do I know which prop to buy? Not really sure on the year either. There is only the serial number on the motor.

 

[Wick77]

Re: Prop slipping?

I'm getting ready to order a new prop for my late 80's 9.9 that has the same problem. The local shop wants $40 bucks to replace the rubber hub. Iboats has brand new Solas Amita props on sale right now for $49.49. Comes to $55 after shipping. Buy a new one and if your old prop is in good shape get the hub replaced and keep it for a backup.

Ok, don't have a manual for my Merc. How do I know which prop to buy? Not sure on the year either. How do I find out more info with just the serial number?

 

[CharlieB]

Re: Prop slipping?

There should be #'s on your prop, look up that prop, diameter and pitch, then search for comparable props.