Changed prop

[mkjwest]

Hi all, when I take off in the boat, and it starts to get on plane the rpm`s go way up and it seems that something is slipping. I already had my prop rebuilt, because I thought it might be the hub slipping. i took it out again and something is still slipping. I checked the marks on the hub and prop and the hub is not slipping. The motor isn`t making any grinding noise. Does any one know what else I can check or might be the problem? Thanks.

 

[Bondo]

Re: Changed prop

The motor isn`t making any grinding noise.

Ayuh,... What motor,..?? What drive,..??

 

[steelespike]

Re: Changed prop

Sounds like you have a ventilation (cavitation)issue.Tell us about your rig.
in detail.Where is the antivent plate ,just above the prop, in relation with the bottom of the transom.

 

[mkjwest]

Re: Changed prop

It is a 18 ft 1994 Tracker Nitro with a 115 hp Mercury pro series motor all stock from factory,no add ons.

 

[steelespike]

Re: Changed prop

Please read "read this first" posted at the top of the page.
Prop size may be on the barrel or under the prop nut.
Please keep in mind we are just fellow boaters with some experience with boating issues when you say you have a 18ft,Tracker Nitro with a 115
Merc pro Its like me telling you I have a 18ft 57 Crestliner Bucaneer with a 65 50 hp Merc 500 and expect you to know the specifics.
Is the prop in excellent condition?Again Where is the antivent plate in relation to the bottom of the boat? below?even? above? how much?
Use a straight edge laid next to the keel. Is this slipping a new developement?

 

[mkjwest]

Re: Changed prop

Hi all, yesterday I lowered the motor on the transom 2 holes to see if it might be a cavitation problem. I`ll try it this weekend to see if that makes a difference. I hope it works, I`m running out of options. I`ll just keep doing a process of elimination until I figure it out. Thanks for all your help

 

[steelespike]

Re: Changed prop

2 holes may be excessive If the motor is the right size for the boat
as little as 1/4 inch might solve your problem assuming it is a height issue.
Of course your tied to what ever your holes are designed like.
Good luck and please feel free to ask any further Qs.