Trim ?

[jj2]

I have a triton tr20 with a 200 merc efi was wondering how high the motor should be able to trim when on plane mine will only trim up to just below the half way marke on the trim guage I was told I should be getting a rooster tale about even with the top of the motor but i'm not getting even a sign of one even with the jack plate allthe way up

[Al Wolbach]

The rooster tail they are talking about is caused by water rushing around the sides of the hull and meeting the prop wash on the centerline of the boat. I'm going to guess and say 20-30' behind the boat. If your boat is set up correctly and trimmed correctly the rooster tail should be about even with the top of the motor. You are probably looking at the stern of the boat but the rooster tail is behind the boat, or at least should be...............Al

[Jig Man]

Where it shows on the trim gauge is not important as it can be changed with a setting and has nothing to do with the actual angle of the motor.

Rooster tails don't matter to me. I look at rpms and speed.

[jj2]

Where it shows on the trim gauge is not important as it can be changed with a setting and has nothing to do with the actual angle of the motor.

Rooster tails don't matter to me. I look at rpms and speed.

the rpm's are running around 5400 and the speed seems pretty slow it tops out at 58 mph

[Way2slow]

The rooster tail is the prop wash. Many use it as a guide line on how well a boat is setup. You trim the boat for proper bow lift, not by the rooster tail. If you don't have enough up trim the boat is going to be running heavy in the water, wetting to much hull, it will never make full rpm or speed. Too much up trim and the prop can start to cavitate, you will actually hear a different sound from the motor. You will also see an rpm increase with no increase in speed. This can also make one chine walk a whole lot more and hard to control the chine walk.

With a good setup, the motor heigth will be right and will be trimed so it's about 90 degrees vertical to the surface of the water, the boat will have just the right amount of bow lift so the hull is running with minimum wetting. The prop will be giving max forward push, pushing straight through the water, making a low roster tail that's about three - three and half feet high.

If the boat has a wrong setup, like not have enough setback, the wrong style prop, motor height wrong etc, it can take more up trim to get enough bow lift to get the hull up. Instead of just pushing forward through the water, the prop is having to push at downward angle as well as forward. All the energy lost pushing downward means slower top speeds. This also directs the prop wash at an upward angle, creating a much higher rooster tail, and more chance of cavitation, more lost power.

If you look at boats runnning down the lake and throwing tall rooster tails, you will see most of their motors are very noticably over trimed, way beyound verticle with the water.

This is because very few want to invest the time and money, or have the know how, to properly setup a boat. Don't think for a second your dealer did it for you.

[South FLA]

Its all about boat setup and each boat is different. Read this and put in the time.

http://www.kencook.net/Setupart.html