Trim Question?

Dsilvers112

Seaman Apprentice
Joined
Jul 1, 2010
Messages
39
What is the best position to run the trim at when cruising?Trying to get on a Plane?
 

Dsilvers112

Seaman Apprentice
Joined
Jul 1, 2010
Messages
39
Re: Trim Question?

kinda new to boating just wondering the best trim position for maximum power??
 

Philster

Captain
Joined
Sep 15, 2009
Messages
3,344
Re: Trim Question?

Trim all the way down/in when getting up on plane. Once on plane, pull back throttle when boat settles in and then trim 'er up/out and you'll hear revs build.

At this point... there is no other answer than "just experiment". Get a feel for where she stops building revs but still bites the water with the prop. You could trim up so far that the prop isn't biting, or the hull is so far out of the water that it porpoises (nose goes up/down in rhythm).

For me, cruising trim and full throttle trim are about the same: I get the drive up/out which lifts the hull and saves me fuel and gives me a good return on the throttle by giving me all the RPM for that given throttle setting.

When it's rough seas, I trim down/in more and maintain more bite/control. If I want to cruise on glass flat water, the darn trim is just as high as if I am making a full throttle run. If I have lots of turning to do, the trim comes down/in a bit. See a pattern here? More bite = more control. Control means more stuff (hull/drive/prop) is in the water, so that = more resitance which = more fuel burned.

You have to practice. A big chunk of your learning curve will be to get on plane with the drive down/in. Get on plane, pull throttle back as she starts to run up and then trim 'er up/out until you see she is building revs and stops building revs. Now you have to find the happy point, which is different for all boats and conditions (as well as preferences).
 

Dsilvers112

Seaman Apprentice
Joined
Jul 1, 2010
Messages
39
Re: Trim Question?

Thanks man. I appreciate your help. That makes really good sense
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: Trim Question?

It depends on what engine, drive, etc you have.....

With the typical Mercruiser/Volvo/Cobra etc that has power trim, you usually run the drive IN (level or all the way down) for initial "hole-shot" and trim it out a little at a time once on a "plane".

You'll notice that when you go past the "sweet spot" the boat speed will decrease or it'll start "porpoising " in slightly choppy water. (Most newer drives have a limit switch that'll prevent you from trimming too far out..(up) )

If that happens, "back it down (in) a little" that's your best position. If you change speed, you will need to tweak it a little in or out.


You didn't say what year drive you have. Some older Merc drives only allowed for tilting the drive at slow speeds. The system must be designed for trimming the drive while running.....


You're much faster typing than me there Philster!!:D


Cheers,


Rick
 

Dsilvers112

Seaman Apprentice
Joined
Jul 1, 2010
Messages
39
Re: Trim Question?

yeah i have learned a lot just playing with it. i noticed it planes out quicker when trimmed all the way down. i do trim it up some when on a plane. it scared me yesterday though made a sharp turn while pulling a tube and it reved real high guessing the prop came out of the water. guess i had it a little too high
 
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