Keel offset

[fmstuart]

For a 32’ CW with twin Yamaha 300s, is the appropriate keel offset 2.5’? I am not sure how deep the skegs on the outboard are.


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[Kevin Lamont]

For a 32’ CW with twin Yamaha 300s, is the appropriate keel offset 2.5’? I am not sure how deep the skegs on the outboard are.


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Hello,

They are about that low however, I would set it for 3ft and see how that works for you. Better be safer than not.

Thanks,
Kevin Lamont

 

[Interlude]

Just to verify Kevin. This offset of 3ft is entered as a NEGATIVE number

 

[Maggie Anne]

Also, once you enter your keel offset, you can see the effect as the difference between the sonar reflection depth shown on the color chart and the large white digital depth value at the top of the screen.

 

[SJI Sailor]

The keel offset (at least on our 7612 chartplotter) is entered as a +x number. As Kevin mentioned, we set ours to +3.0 feet.

I recently measured with a plumb line, and 19.0 feet actual (from water line in cockpit) showed as 16.0 on the chartplotter, +- some inches, using a +3.0 offset.

As Maggie Anne noted, you can see both of them on the sonar chart. The offset only changes the big number, while the scale on the sonar reads the nominal. For example, with our offset +3.0 the big number might read 20.0 but the bottom on the smaller scale on the sonar (distance from transducer) reads 22.5 etc. Good idea to check it there.

 

[rpmerrill]

When I originally got the boat the Garmin instructions and tugnuts posts were all confusing me. Even setting the number at +2 or -2 wasn't totally conclusive enough for me.

So I set it at +10 and then -10 and the answer was obvious. I cant even remember if it is a positive or negative number that works.

 

[Shibumi]

I use 4 feet. I’ve discovered that a prop kicks small rocks off bottom. And that can get expensive. Remember there is no keel there—just a lower unit hanging down.