Thruhull transducer on a classic 20, what degree?
 

Pretty simple question. I'm looking at adding a thru hull transducer, probably an airmar b60 as I've had good luck with them in the past. Just wondering what degree I should get. They come in 12 and 20 degrees.

I assume 20 but just wanted to check the brain trust first.

20 it is for my 20. I have the same one and it shows bottom at 28 knots

Thanks, that's what I wanted to hear.

How far forward from the transom did you mount it?

I can't remember for sure and I'm 300 miles from the boat right now for the fourth. I thought I took pics of that but can't find that either. Just find a spot as far back as possible that has the required 20 degree and go with that. Make sure there are no other they hulls forward of it that would cause air bubbles to flow over transducer and cause a bad signal. Remind me Monday and I can give you the exact location of mine.

Will do thanks!

About 4 feet forward of the stern just starboard of centerline.

Thanks a bunch...that seems to be where I was thinking, but I needed some Immoral support before I cut that 2 3/8" hole...in this case measure 6 times cut once.

Yeah Terry, when I drilled the 3 3/4" hole for the B-164 Airmar it gave me a super case of "pucker power"!! :)

it is an un nerving feeling cut that big a hole in the bottom. i expected to see alot thicker hull than i found too. works great though. good luck

I only went about 2' forward, but I have a bracket so wasn't too worried about prop wash. Works great. I used life seal instead of 5200, and I know there are various schools of thought on which is better, but I've had good luck with it in this sort of application.

Put her to the test a few times, doesn't lose bottom at any speed, or backing down either. Though we didn't back down crazy hard.

I've had them done before, never done one myself. Watched a BOE marine video before doing it. Would highly recommend this and any of their videos prior to electrical installs.