Best place to drill hole for transducer?

Handymans342

Where would be the best place on a 342 to drill a hole and install a thru hull transducer? I was thinking in the mid-berth area by the bilge pump. Has anyone installed one? Per MT I have extra bits!!

pault1216

Just a plan "B" but I installed one in one of my runabouts without the hole. I sanded an area flat and smooth in the bilge near the transom and glued it in place. I then dropped a piece of PVC pipe over the transducer, threading the cable though it and an end- cap with a hole in. I glued the cap on the pipe and filled it with mineral oil (eliminates air pockets) and then plugged the hole in the top with silicone sealer.  -Paul

frodo13056

My 08 320 came with a thru-hull transducer but when I installed my Lowrance equipment, I did the epoxy installation of the new transducer - there is a lot of information on how to do it if you use google. I epoxied mine in 7 years ago and it still works perfectly. Best thing about it was it runs on a different frequency than the OEM transducer (also Lowrance) and I can run both with no interference between the two transducers. This way, I always have a back-up depth indication. I just selected a spot near the generator water intake thru hull, cleaned the area with acetone, used the Lowrance transducer epoxy, glued it in and done. I did place the transducer in a small plastic container filled with water to make sure that the transducer would "shoot through the hull" before I actually epoxied it in.
I used the Lowrance Epoxy Kit 10698
Here's a video showing how to do it:
https://www.youtube.com/watch?v=22SzRXa21hg

Handymans342

Yeah I just dont like that idea Frodo but thanks

Handymans342

Its the new type and its for fishfinder and depth

MarkB

A through hull transducer is not normally drilled through, it's glued with epoxy to a flat section of the hull inside the boat.

MarkB

This is what all the pro fishermen do handy. No one drills a hole into their hull. It works better if it's epoxied to the hull becuase then your entire hull becomes a receiver. I've seen a transom mount transducer and a through hull work ... experience with both for many years, and the through hull (glued) outperforms by a long shot if installed properly.

Handymans342

Mark, do you have a picture of yours? 

Handymans342

There are 3 types. Transom mount, thru hull and thru hull mounted inside. I have the thru hull with a high speed fairing. Recommended for boats 30 feet and above. Plus I want accuracy to 1200 feet. I want to see the Titanic on the bottom LOL

Handymans342

Thanks AL, I have to cut the fairing block now on a 20 degree angle. 

MarkB

I used a transom mount.  My fishing partner has a 33 ft pursuit and has the through hull.  The detail is amazing even at higher speeds. 

Handymans342

Yes Mark. That's what I want to have. You need the clarity around here.

randy56

Looking for sunken treasure, 

Handymans342

Sand bars, etc.

MarkB

Handy what do you want to see.  Because you may want to point the transducer forward or backward a bit depending.  But that does introduce angle which gives you a false depth reading (will appear deeper than what it actually is). 

Handymans342

Mark, will that make a huge difference? The fairing and the transducer will be mashed tight to the hull so I dont think you can get any angle on it. Thanks

MarkB

With the through hull epoxied in or the transom mount, you can obviously angle forward or back. Most guys angle back so they can catch a glimpse of their tackle to estimate how deep they are (although it isn't accurate).  If you're drilling through, I don't think you'll have that option.

Handymans342

Mark, I will just buy my fish at the market.

MarkB

LOL. Not as fun ...

kuhnr7

Handymans342 do you have any photos of what you did. I'm in the cape also, and am looking to update mine to the Raymarine axiom with a through hall mount transducers 

Handymans342

Would be glad to help in any way but the guy who did my gelcoat is gone. 

davidbrooks

@Handymans342 did you drill and install the transducer?  I would love to see pics of the transducer installation if you took them.  I put in a transom mounted one last year as it came with the unit but i keep thinking about a through hull or in hull one. 

Handymans342

On my 342 its in the mid berth bilge area but this is a bad spot because it won't work at top speed and I forgot to look at it at cruising speed. Will try this weekend

davidbrooks

Even my transom mounted transducer wont work over 22-24 mph.  May not be the location.

MarkB

The only transducers I've seen work at higher speeds are through hulls, not transom mount.

Handymans342

I believe my thru hull is right at the plane location at top speed

davidbrooks

Well that would make sense why it wasn't working.

bry1429

Installed a CPT-120 high speed bronze transducer, (I cut the fairing block to an 18° angle), along with the CP-100 downvision.  the hard part was the drilling of a hole in a perfectly good boat bottom   
My e95 Raymarine mfd has and now I can utilize the  bottom scan and temperature

Handymans342

Where did you install it?

bry1429

@Handymans342 ,  2' from transom wall and approximately 16" from centerline 

jmichels

bry1429 said:

Installed a CPT-120 high speed bronze transducer, (I cut the fairing block to an 18° angle), along with the CP-100 downvision.  the hard part was the drilling of a hole in a perfectly good boat bottom   
My e95 Raymarine mfd has and now I can utilize the  bottom scan and temperature

Love to see some images of the down vision. I have a E97 and just bought the CPT-120. Need some convincing to show me its worth cutting and installing lol