Can someone translate and explain for a 1st time boater?

[Xesvuli420]

So I just installed a new Trim Sending Unit on my boat, as well as a new Trim Gauge. I understand that I should put the stern all the way down, and then turn the Sending Unit until the Trim Gauge reads FULL DOWN, then tighten the Sending Units bolts, and move on to step 2 of the calibration. If this is wrong in anyway let me know!

Step 2 is where I get confused. The instructions say...

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"Post Installation Adjustment
1.Before adjusting the T'N'T Power Trim/Tilt Gauge, the gearcase Trim Tab Adjustment must be completed as described in the units owners manual. This adjustment is necessary to balance steering forces and allow the boat to obtain maximum speed. The boat should have the normal anticipated load for this adjustment.

2.While operating boat at full throttle, trim propulsion unit until optimum performance is obtained. Optimum Performance will be the maximum boat speed without propeller ventilation (slippage).

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First, what is/does T'N'T mean?
Second, what is a Gearcase Trim Tab, and how do you make an Adjustment
And Finally... Balancing Steering Forces?

I think I kinda understand the rest of the instructions, basically its telling me to get on a plain at full tilt down, then slowly raise my trim until I reach maximum speed, then leave the trim alone, and come to a stop. That is when I adjust the Trim Gauge to say that the current trim angle is the highest level of trim I should use.

Guys listen, this is my first time ever even using a boat, so I am really dumb to what I need to do. Please sit down, crack your knuckles, and help ole Charlie Brown understand what I need to do. I appreciate all your help, and would REALLY appreciate if you thoroughly explain this to me. Thanks everyone!

 

[83Evinrude]

Re: Can someone translate and explain for a 1st time boater?

First, what is/does T'N'T mean?
Trim and Tilt

Second, what is a Gearcase Trim Tab, and how do you make an Adjustment
If you don't have power steering there is a bolt holding a small plate with a rudder on it. Its under the cavitation plate (big plate just above the top of the prop). It can be adjusted to cancel out engine torque although this will vary with speed and trim angle.

And Finally... Balancing Steering Forces?
If you can remove your hands from the steering wheel when running down the lake (very carefully in case its way out of balance) its already fine without adjusting the trim tab. If you have power steering you probably don't have the tab any way.

 

[haulnazz15]

Re: Can someone translate and explain for a 1st time boater?

1) T'N'T sounds like Tilt-N-Trim
2) The zinc metal "fin" (above the prop) can be adjusted on the outdrive to combat steering forces, but some models don't include the trim tab any more.

*Note: I don't know why you would need to adjust the tab anyway, if all you did was install a trim sensor/gauge, the steering forces shouldn't have changed.

When trimming the motor at full throttle, trim up until the boat begins "porpoising", then trim down just enough to make it stop. That is the optimal trim setting for wide open throttle. However, you shouldn't be cruising at WOT for long periods of time, so it's not really that important. After boating a while, you will learn what looks/feels right for the trim.

 

[bruceb58]

Re: Can someone translate and explain for a 1st time boater?

The adjustment of the trim tab has nothing to do with your adjustment of the sender.

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

First, what is/does T'N'T mean?
Trim and Tilt

Duh! lmao I am soooo stupid sometimes!

Second, what is a Gearcase Trim Tab, and how do you make an Adjustment
If you don't have power steering there is a bolt holding a small plate with a rudder on it. Its under the cavitation plate (big plate just above the top of the prop). It can be adjusted to cancel out engine torque although this will vary with speed and trim angle.

I do have one of these, I noticed that it is left of it being centered. I also know that under load the boat tries to go to the left coming onto plain, I really have to fight the steering wheel to keep it strait until we plain out... I wonder if they are related. at what position generally should this tab be, Or how do I know if I need to adjust it?

And Finally... Balancing Steering Forces?
If you can remove your hands from the steering wheel when running down the lake (very carefully in case its way out of balance) its already fine without adjusting the trim tab. If you have power steering you probably don't have the tab any way.

Besides it trying to go left when I WOT, the boat does seem to steer itself strait.

Thank you so much for your explanations!

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

1)*Note: I don't know why you would need to adjust the tab anyway, if all you did was install a trim sensor/gauge, the steering forces shouldn't have changed.

I don't know either, but the instructions for Gauge installation says to do it, Shoot sounds to me like this could be something I could adjust to make my boat handle better, Maybe that is why when I WOT to get on plain, the boat tries its hardest to go left.

When trimming the motor at full throttle, trim up until the boat begins "porpoising", then trim down just enough to make it stop. That is the optimal trim setting for wide open throttle. However, you shouldn't be cruising at WOT for long periods of time, so it's not really that important. After boating a while, you will learn what looks/feels right for the trim.

I assume by "porpoising" you mean that magic spot where the bow starts to rise... correct?

Thanks for your help!

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

The adjustment of the trim tab has nothing to do with your adjustment of the sender.

In my first post I typed the instructions word for word. In the instructions it clearly says to adjust this. I assume they are trying to get me to get the boat in perfect order before I set the gauge. I'm not really sure, but if it wasn't important, or at least a precaution, it wouldn't be in the instructions.

But thanks anyways

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

Bump..

 

[haulnazz15]

Re: Can someone translate and explain for a 1st time boater?

No, porpoising (sp?) is when you boat acts like a porpoise jumping in and out of the water. In the case of your boat, when you're at full throttle with the drive down, it won't happen. As you trim up, still at full throttle, you will reach a point when the bow starts bouncing up and down: that is porpoising. Now when you reach that point, simply trim down enough to make it stop. That point when it stables out, is the maximum "up" limit you would want at full throttle.

However, I don't know if that somehow when you stop and set this "upper limit" that it would indicate at the top of the arc on your trim gauge or not. When moving in really shallow water at idle, you can trim up till the prop is at the top of the water and still be "safe". Just don't do it over idle speed.

 

[hoot]

Re: Can someone translate and explain for a 1st time boater?

The outdrive has a trim sending unit and a trim limit sender. The limit sender stops the outdrive from going up too far during operation. Too much tilt will destroy the universals. Do a search for outdrive trim adjustment or some of the manuals loaded by Don above in the sticky section might give instructions. The tilt up allowed during operation is not much. You should have switches somewhere labeled up/out, in, out, or trailer or something like that. The tilt for trailering is more than running and the limit sender is bypassed to get it up higher. Porpoising is when the speed and tilt are not matched. The front of the boat will bounce severely sometimes, trim down to stop this. The bow (front) will always rise during accelerating regardless of trim setting. For boating, start with the outdrive down and trim up as you go/get to speed to get more speed and a better ride.

 

[bruceb58]

Re: Can someone translate and explain for a 1st time boater?

In my first post I typed the instructions word for word. In the instructions it clearly says to adjust this. I assume they are trying to get me to get the boat in perfect order before I set the gauge.

No matter what it says...it still doesn't matter. If the instructions said to beep your horn twice before you start would be equivalent

 

[bruceb58]

Re: Can someone translate and explain for a 1st time boater?

The outdrive has a trim sending unit and a trim limit sender. The limit sender stops the outdrive from going up too far during operation.

Not on am OMC Cobra.

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

Not on am OMC Cobra.

haha, beat me to it brucie! lol


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Ok new problem guys.
I took the boat out today for a complete test (everything but the WOT trim up porpoising thing, because I took my grandpa to fish, and I didnt want to WOT with him aboard. he's frail =o)). With the sender installed, and the stern ALL THE WAY DOWN, I was still reading 2 on the trim gauge. Remember this gauge says TILT in yellow, and when the stern makes contact with the arm of the Sender it starts at 3, goes to 2, then 1, then 0. Kinda like this (use your imagination)

Tilt
3
2
1
0

So with the stern fully DOWN, being at 2 is in the middle. I grabbed my ratchet, and jumped in the water, loosened the bolt, and turned the Sending unit as far as I could. (BTW its hard to swim, hold a Sending unit, and tighten bolts at the same time!) After the adjustment, I managed to get it down to 1.5. So I removed the Sender, and taped black tape around the contact point of the arm about 15 times. I know its not permanent, but I managed to get it down to 0.5 now. I know a little more black tape will do the job, but it wont last! Is there anything I can to to adjust it further without using the black tape?

BTW(again) Now that I finally got the trim almost working, It makes learning so much easier, and i love the fact that I don't have to LISTEN for the gurgling to know when my prop is fully down. (can't be good for the hydralics, or pump)

Any ideas?
Thanks again you guys, Im lucky to have people like you!

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

Bump...

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

really? No one knows what to do? lol

 

[haulnazz15]

Re: Can someone translate and explain for a 1st time boater?

I don't know why you bothered with the trim guage anyway. It's a reference tool, but you should be able to tell when you have the trim adjusted correctly by how the boat is handling. Many boats don't even have trim guages.

In any case, there has to be a bottom position you can set in your driveway, you shouldn't have to be at WOT to set it.

 

[Xesvuli420]

Re: Can someone translate and explain for a 1st time boater?

I don't know why you bothered with the trim guage anyway. It's a reference tool, but you should be able to tell when you have the trim adjusted correctly by how the boat is handling. Many boats don't even have trim guages.

In any case, there has to be a bottom position you can set in your driveway, you shouldn't have to be at WOT to set it.

really? did you not read any of my last post? haha gee thanks!