Proper Trim on 22

P

Peter_BDA

New member
Hey all,

This is directed to my fellow 22 cruisers; I am trying to get some guidance on trimming my boat properly with engine and Bennett trim tabs. I understand every boat is different and I have to experiment a bit.

So, the general question is do I use both engine and trim tabs or one over the other? Also at what speed or rpm do most 22's start breaking into a plane? I am assuming this is where the efficient use of trim tabs will help?

Any advice would be appreciated!

Ta
Peter
 
its a matter of touch and feel and I know some people have a hard time with that and want numbers. rpm, trim degree etc..

I always start with the motors. I always start with the motor in the full down position and get up on plane. As soon as I do I trim the boat up, raise the front end, by bringing the motor up until 1) the ride is uncomfortable or 2) the prop skips out ( rpm will jump up) then I bring is down a little. Once you have that set I use the trim tabs to trim the boat, which to me is a side to side thing not a bow up or down, that's what the motor is for.

Once the side to side is set and I hit a little chop I lower the motor is bring down the hull down to cut the chop like in a rip tide. If the water smooths out again I use the motor to bring the bow up again, not the trim tabs.

so motor bow up and down
trim tabs side to side.

The only way to truly know what is the most efficient is to use a flow meter on the fuel. I just put one in and cant wait to see what the best speed is. I know that when Jim put in his flow meter he was surprised at what his most efficient speed was. It was faster then he thought it would be. Hope that helped but no numbers today, you have to feel it.
 
I do something similar to Tom, but have never trimmed up enough to have the props skip out. I recently added Permatrims to the twin 35's so I can get a little more adjustment. It is naturally hard to determine when you are actually on plane but somewhere around 13 is about right. If you have GPS you can play with the trim to look for the best speed, but at least on my boat I can sort of hear it when I am trimmed down too far, I lose about a knot, the bow dips down, and the rpm decreases slightly, so then I raise the trim and it all comes back up. You should be able to actually sense it when you are too far down. I can also use the individual engines to correct lateral imbalance, but usually it will but me into a bit of too trimmed down on one engine to be most efficient. Too far trimmed up and your nose will be too high to get a good close up view of the water, and will pound in a chop.
 
A trick I use generally is to get the bow down with trim tabs, and the engine when first coming up on a plane. In many boats adjustment is not necessary to full down position.

After the boat is on a plane, I gradually bring the engine back to neutral and then use the tabs to allow the boat to run level, and get the best ride for the conditions (bow up down wind and waves, bow down into the chop--half way between when in beam seas). Be perticularly carefull with too much bow down when going down wind/seas--you can end up bow steering and even broaching.

Finally I trim the engine in small incriments to see where the RPM and speed picks up to the most--without touching the throttle. Sometimes this will result in going faster than you want, so you pull back slightly on the throttle. Generally this will be the most effecient setting for the engine--and will correspond with the best fuel economy.
 
Adding to Thataway Bob’s comments, the boat's propeller operates most efficiently when the thrust is parallel to the water surface. This suggests that when on plane and cruising in choppy conditions, the bow should be trimmed down with the tabs for comfortable ride and then the engine trimmed for max efficiency which most likely is where the thrust is horizontal.
 
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