how to use trim tabs? tilting motor on plane

[basswacker]

How do you use your trim tabs/tilting motor when on plane. When I put the motor in gear I have it all the way down one the rpms are up to where I want them I raise the motor but how much? And do I just use the trim tabs to balance side to side? My dad says the boat plows too much when cruising but he has no clue about the trim tabs/trim/tilt.

[ScottM]

Tabs are mainly to balance loads side to side but they can also be used to get the boat on plane quicker by putting them all the way down. Then as the boat gets up, raise them and only adjust if load dictates. Using the engine trim will adjust the boat's running angle for sure, but the SC's, particularly the 23s, run fairly flat under way to utilize the VDH so you're not going to get whole lot of upward running angle. If you really want to see what she'll do at WOT, trim the engine out until the prop starts to ventilate/break free, then you'll know when you've gone too far.

[Fr. Frank]

If you really want to see what she'll do at WOT, trim the engine out until the prop starts to ventilate/break free, then you'll know when you've gone too far.

Wait 'til you're at WOT before you start trimming out for max trim angle, as the max trim angle will be different at different speeds. Once the prop starts to ventilate, just tuck the motor down a bit 'til you feel it/hear it bite fully once more. If you're using a steering cable. instead of hydraulics, steering at proper trim will be neutral with no pull to either side (assuming you're using a factory torque tab behind the prop that is positioned properly)

[oldfielder]

As I just came back from a pretty snotty day in Montauk, I would add that they will help you keep the bow working in a tight chop. Typically, without them, I will not ride nearly as well through the tightly packed 2-3 foot chop in the sound and mtk, as the bow will get lifted and not have time to recover. They definitely create some drag, but pinning that bow down really changes the ride.
Same thing on my small Steiger skiff.

[Bushwacker]

Fr. Frank gave you a great answer on how to set engine trim. With my old 20" shaft motor on the transom, I found engine trim had little effect on the boat's running angle, and I generally just trimmed it out as far as possible to minimize drag of the lower unit. Now with the 25" shaft motor on a bracket with 30" setback, the motor evidently has much more leverage because engine trim now has a big effect on running angle and that's my primary control for running angle. One note of caution - In following seas, you generally want the bow trimmed up (Motor and tabs up); the boat can get squirly and hard to handle if the bow is trimmed down in those conditions.

Regarding trim tabs, the more you lower them, the more drag they'll cause, so I normally try to minimize their use, but when it gets rough enough, I quit worrying about gas mileage and use them as required to improve ride! How soon that happens depends on how high your threshold of pain is!

Deep-V's tend to lean into the wind (wind blows you off course, so when you crank in some rudder to correct, the boat heals over as it does anytime you turn the wheel). You will find that if your desired course has you running into the waves at anything other than directly head on, rolling the boat AWAY from the waves by just a few degrees, either by shifting gear around or using the tabs, will make a significant improvement in the ride. This is because you are essentially increasing the deadrise of the hull relative to the waves!

When you're in a short steep chop, like the 2' square waves common on the Bahama bank, you have 2 choices - either put 'er up on top at about 30-35 mph and just hit the tops of the waves, or trim everything down to min planing speed and slog along in comfort at 12-13 mph! If your boat isn't balanced well enough to plane that slow, you might want to consider a doelfin or equivalent and/or a good stern-lifting 4-blade prop. If none of that works, you may prefer the high speed approach!

[2182]

not sure if your rig is bracketed but many bracketed boats sit lower at the stern and are more prone to bow rise. i use my tabs more than most (who responded), but i also run a small boat in rough water. in ideal conditions (VDH aside), the idea is to have as little boat in the water as possible to run the smoothest (think bass boat going 70), and trim tabs will help you achieve this. the inverse is that they will also hold your bow down when needed, generally into a tight head sea, as someone else mentioned. go out and experiment, and you will have it down in no time. i fish w/ a guy who weighs 300 easy, and w a little tweaking the boat runs smooth all day.