85Baja

Im contemplating buying a new GPS unit that has a built in sonar. I would like to know what you guys think of transom mount transducers on a go fast boat. I think a shoot thru the hull puck stlye looks like a cleaner installation because the transom mount has wires hanging down the transom. However, I also heard alot of negative things about in hull transducers like they werent sensitive enough and the installation was very precise or else it wouldnt work right. The transom mount would be nice because it also will tell you water temp along with depth where the puck style only tells depth.

But will the transom mount one get damaged running at 60MPH? Just want to know what holds up at speed and will be more trouble free operation.

Dave M

I had a transom mount on my previous boat. The boat ran in the upper 70's. It never damaged the transducer, but it didn't read at speed either.

My current boat has a shoot thru transducer and the performance is pretty erratic. It seems to read OK at idle or low speed but not when going fast.

Honestly, if I have any question about the water depth, I'm not going to be going very fast, or even be on plane.

RaggedEdge

On any boat that I have owned over the years that ran decent speed I've never been able to keep a transom mount on the boat. Most blew off within a very short time.

Thru hulls can be a little eratic in how they function, speed will often render them somewhat useless. I have come to the opinion that at speed you best be sure of where you are. A little warning beep will be too little too late at speed.

Too Stroked

As others have said, a transom mount - mounted correctly - will generally give more accurate readings. On the negative side, they add drag and thus tend to get pulled off at higher speeds. They also look like heck.

The thru hull style leave your transom looking much cleaner, don't add drag and mounted correctly - can read reasonably accurately. That's the trick though - mounting them correctly. The biggest problem is finding a place in the bilge you can get to that doesn't have any air bubbles in the layup. Mounting one correctly is something of an art form. Oh, and replacing one that was mounted correctly is a royal pain.

So, that makes it perfectly clean now doesn't it. Sorry.

Sledge Hammer

I use a through hull type in my Baja and it works great at speed. To find the right spot I put it in a baggy filled with water which will allow it to shoot through the hull. You have to find a place that is not cored with wood. On mine it was the keel or pad near the rear of the boat. I think some may mount it too far forward or two much to the side which allows air under that portion of the hull. I simply epoxied it to the floor. However you have to make sure you don't stir the epoxy so much that you create air bubbles or it won't work right.

blownhammer2000

iTrader: (1)

+1 on the water in a bag, works great to find that sweet spot, also agree that if water depth is unknown usually at idle or boating w someone who has knowledge of that particular water, my baja had a shoot thru that worked great all the time, even at speed, now the nordic is another story, shoot thru again but the stepped hull creates turbulence which only allows readings up to 15-20 mph, general knowledge of your water is a must in any situation in my opinion

Too Stroked

And putting the puck in a bag of water to find the best mounting location is just part of that "art form" I mentioned. I use it every time.