Bow Out of the Water Question

gciccol

Cadet
Joined
Mar 3, 2009
Messages
14
I have a 16 foot 1970 Starcraft Super Sport V boat powered by a 1970 Mercury 65 outboard with a Quicksilver model 2036 P17 propeller.

When I throttle up the bow comes out of the water and the engine dogs. At full throttle I go about 70 percent of its available speed. :mad:

I think I've got the weight distribution pretty balanced on the boat. However, if I have my heavy buddy go sit right at the bow the boat goes on plane and the engine runs much smoother.:)

I've seen generic Hydrofoils at the Bass Pro Shop and was wondering if that would help my situation. Any suggestions would be much appreciated. Thanks
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,089
Re: Bow Out of the Water Question

Ayuh,... Have you tried changing the Trim of the Motor positions,..??
 

ezmobee

Supreme Mariner
Joined
Mar 26, 2007
Messages
23,767
Re: Bow Out of the Water Question

Forget the hydrofoil. Trim playing with your trim as Bondo suggested. If that doesn't help then this sounds like an excellent case for Smart Tabs. They'll really help get your stern up and out of the water.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,099
Re: Bow Out of the Water Question

The engine should be propped to hit it's max recommended RPM at WOT with normal weight aboard. Can you get to 5500 RPM or so? If not your prop has too much pitch. A 15" pitch prop of the same type wil raise the RPM at WOT by about 400RPM. it will also help the hole shot.
 

haskindm

Petty Officer 1st Class
Joined
Jun 12, 2008
Messages
255
Re: Bow Out of the Water Question

You may also want to make sure that your foam flotation is not waterlogged and adding weight to your rig. If you do not have a tachometer installed, you should get one to make sure that your engine is reaching the proper RPM.
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: Bow Out of the Water Question

I used to have a Super Sport. If the boat is in good shape (bottom is not hooked or rockered) and the motor is set up correctly (propped right? trimmed right?) then it ought to ride quite nicely with your 65hp. Adding fins or tabs are merely band-aids in this case as it ought to ride fine without either added...
- Scott
 

gciccol

Cadet
Joined
Mar 3, 2009
Messages
14
Re: Bow Out of the Water Question

Thanks to everyone for the helpful responses. As you may tell, I'm a rookie boat owner. I've found this site to be an excellent source of information. Based on your suggestions regarding the trim, I've done some additional research here and believe you guys have nailed it.

I will be taking the boat out on Monday and will test the trim and how the boat is planing. I know that the bow always seems to be out of the water, both when I'm at a higher throttle and when I encounter choppy water.

I plan to test how the boat is planing boat without doing anything to the trim. Once I'm sure how it's cruising on the water I will adjust in increments until it seems to be planning correctly.

Thanks for all your guidance and help.
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: Bow Out of the Water Question

Keep in mind that the bow is SUPPOSED to ride out of the water at speed. You do not want the bow buried while running at speed as it is A) more efficient to have the bow out of the water a bit, and B) can be dangerous if the bow dives into a wake or wave rather than riding over it. You don't want the bow to ride so high that it affects your visibility from the cockpit, or that it bounces around continually. In calm water, properly trimmed, your boat should ride smoothly with the water breaking maybe midway down the keel.

- Scott
 

gciccol

Cadet
Joined
Mar 3, 2009
Messages
14
Re: Bow Out of the Water Question

Thanks for the additional info regarding how the bow should ride on the water. I made a minor adjustment to the engine trim and the boat ran much smoother over the water. I could see over the bow while driving!

Taking the boat up to a busy lake for some fishing in a few weeks. Will see how it handles the choppy water and wakes.

Another question: I've noticed the boat leaks water from directly under the bow for some time after I get it on the trailer (over an hour). There appears to be some type of sealing caulk on the edges of the center rib of the bow. I suspect someone tried to seal it at one time.

Can anyone recommed the proper sealing caulk to use on the edges of the bow trim going under the boat? Thanks again for all the helpful information.
 
Top