Trim up vs. Trailer position.

SeaDooSam

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Feb 15, 2016
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Hi!
I was wondering what the difference is between trim up and trailer position. There seems to be a big difference between the two as far as damaging the outdrive goes when running. Does anyone have a diagram to show up position vs trailer position.
For example I am looking at a new Monterey Montura 196 and it says "Draft-Stern Drive Up" is 22 inches. What exactly does that mean? Thanks
In advance !
 

GA_Boater

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Trim is moving the prop thrust over a small range to match the boat attitude/speed for best performance. The lower unit and prop will be lower than the bottom of the boat.

Trailer is raising the prop and lower unit above the bottom of the boat for safe towing or ramp retrieval.. The engine should not be operated when in the trailer positio because it will damage the drive.

In the Monterey case, draft means 22 inches of lower unit is hanging under the lowest part of the hull when fully trimmed up. In other words, if you are boating in water less than about 3 feet deep grab the checkbook. You chances of hitting the prop or lower unit on something is good because the bottom of a lake or anywhere is seldom smooth. Plenty of stuff is sticking up just waiting to damage your new boat.
 

Bondo

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and it says "Draft-Stern Drive Up" is 22 inches. What exactly does that mean?

Ayuh,..... That means you can shut off the motor, 'n tilt the drive all the way up, 'n float over a rock 23" deep,.... Maybe,.....

Like Gab says, trim is as high as ya wanta run it, tilt is for clearance,....

In the water, 'n runnin' across the pond, ya usually start porpoisin' real bad before ya get to the trim limit,....
 

SeaDooSam

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Feb 15, 2016
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575
Ok I am pretty sure I understand what you guys are saying. Great answers. Very helpful! So basically it would be good to have 4 ft minimum I would guess. At my dock, I think there is about 5 ft at the highest and 3 ft at the lowest (they raise and lower the lake level). So I don't think it would be good to have that boat in at the lowest. Also, I am probably going to be loading it up with 8 people or so. Do you know how much that affects the draft? Thanks again!
 

Bondo

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Also, I am probably going to be loading it up with 8 people or so. Do you know how much that affects the draft?

Ayuh,.... Dependin' on where they're sittin', it Will affect the draft,....

Best way to know for Sure is with a tape measure, 'n pencil marks on the hull at the water levels seen, with those loads,....
 

stonyloam

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Mar 13, 2009
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It sounds like with the outdrive all the way up the depth from the waterline to the lowest point of the keel is 22". I assume that is with no one on board and a full fuel tank, but that may not be the case. You will want to measure ( on the trailer) the distance from the keel to the bottom of the skeg and add that to the draft. Say the skeg is 16" below, 22+16= 38 inches. Do the same with the outdrive TRIMMED all the way up. That should give you an idea of where you can operate under power. As for the passengers, make a mark on the transom at the waterline and pile the folks in and measure how much lower she sits. If you do not already have one, get yourself a depth finder ( even the very inexpensive ones are pretty accurately) and keep an eye on your depth. Good luck.
 

SeaDooSam

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Feb 15, 2016
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ok thanks, i think the boat has a depth finder. ill do what you said.
 
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