Help!

[DonHof]

I have a new 14.75 Lund fishing boat. I have 30 hp Merc on it that's Max.
If the wife and I are in the boat it runs great. If I put a trolling motor battery in the back it will not come up on plane. I think the dealer said he put a 11 pitch prop on it. Any help would be appreciated.

Thanks
Don

 

[steelespike]

Re: Help!

11" prop is in the middle of of the prop list shaded slightly toward the lower pitches
for heavier loads. what year motor,2 or 4 stroke?max rated rpm?boat weight?
Wrong place for the battery if it was just behind or in front of the middle seat it probably would plane.In a relatively small boat weight and weight distribution are critical.Motor height and trim as well. Did you try trimming the motor in?move the wife forward? anchor and/or gas tank forward. We used to plane with 4 adults about 160 lbs average in our old Lonestar 15ft w a 25 Gale.not fast but on plane.
While you could go to a smaller pitch we don't know your present max rpm and speed.Its important the the motor be able to operate within its rated rpm range.
A tinytach is about $40 and easy to install.perhaps you could borrow a gps for speed.Anti vent (cavitation)plate just above prop should be at least even with the bottom of the boat.In the extreme you could gain a couple of mph.

 

[DonHof]

Re: Help!

Motor is 2010 4 stroke, 6100 rpm. Boat weights about 585 lbs. The boat came with both battery trays in the back. Gas tank is set up in the back.
I did move the wife forward and it planed. Had the trim all the way in. With
out the battery in the back I can run about 21 mph at 5900 rpm.

 

[steelespike]

Re: Help!

Gee that seems like a poor setup; I guess you need to put anything else forward.
I believe there is a 4 blade 11" solas amita prop available should solve the planing issue might lose a little rpm,top end. perhaps a 10" if available would hold up the rpm
and you would get the 4 blade and pitch change boost.