Announcement

Collapse
No announcement yet.

In-Hull transducer

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • In-Hull transducer

    My 28 hull already has two old transducers mounted through the hull and one on the transom. They are all very old tech and I'm going to upgrade my electronics this Spring. Does anyone here have experience using an in-hull transducer in their Glasply? The kind that mount on the inside of the hull and shoot the beam through the fiberglass. Seems like these solid hulls would be good for this style without drilling another hole. Just wondering if there is any loss of performance with this style of ducer. I do a lot of shrimping at 400' + and also regularly fish over 800'+ for rockfish and halibut. I want a powerful transducer that will give a good image in deep water.
    http://www.airmar.com/productdescription.html?id=38

    I'm in the process of tearing up the house floor to remodel. I could add a small hatch and mount it near the galley area, just port of centerline.
    1986 Glasply 28' long cabin

  • #2
    I added a thru hull outboard the stringer and just forward of the stbd v drive/transmission. I used a b744v, think I copied billv’s choice. There’s no core so a shoot thru should work well on this hull?

    Comment


    • #3
      I've installed through hull transducers on both my 17 and 23, they work better than exterior transom mounts in my opinion. That said, I don't fish in 400 or 800 feet of water...
      1978 17' Runabout - AQ120B/270
      1978 23' Cuddy

      Comment


      • #4
        Good choice Mike, mine is mounted directly under floor of hanging locker starboard side. I do fish in 300 feet of water too.
        "Joint Venture" 1978 midcabin 28', twin 2017 Vortec roller cam "bullet proof" 383/6.3L full roller 350hp engines - You name it, I've either replaced it, restored it, rebuilt it, repainted it or repaired it. That's my job now that I'm retired.

        Comment


        • #5
          I mounted a "in-hull" on our 24, its a Garmin GT15, mounted between the stringers, right under the motor, slightly offset. I believe the hull is about 3/8" thick in that spot and thicker right in the center. It works good and holds bottom better than the GT51 transom mount. I have them both connected and it defaults to the 15. Unless I choose a view that the 15 doesn't support, maybe 3d and birdseye. I suspect your 28 is thicker there is a limit. Try it. I suspect it will in a GP due to the fact the glass is solid. My opinion is too mount it as far back as possible, as I think there would be less aerated water, stay away from any strakes. Mine is probably about 3.5 to 4 feet from the end of the boat, and I have noticed it will lose bottom if I trim the bow up beyond a certain point. It reads full depth at cruise speed under MOST conditions. There are still occasions when it will not hold.


          Really the best... I believe is thru-hull.
          1982 2580 "HI-BOY " IN 2 DEEP 5.7LX ALPHA

          Comment


          • #6
            Finally made a decision on the electronics upgrade. I went with a top end Garmin system: 8610xsv with a M265 chirp in-hull transducer. I was looking hard at the thru-hull version of the transducer but the thing is 22" long with the fairing. I wasn't thrilled about having something that big under the boat. The in-hull version is only supposed to lose a max of 11% range for a 1" hull thickness. Since it has a range of 3000' that will be plenty of depth.

            My plan is to cut a floor hatch in the area in front of the galley sink and mount it there. This is just outside of the centerline glassed box where the water tank is.

            Does anybody know what the the expected hull thickness is in this area (forward of engine room bulkhead, port of centerline)?

            Also, I'm wondering if the 28 hull thickness is variable depending on the whether there are strakes in that section? The area I'm looking at seems to be on a flat section that is inside of the first strake (closest to center). If anybody has some info on the hull construction or thickness it would be appreciated. I'm not sure if there are any air gaps where the strakes are located?
            1986 Glasply 28' long cabin

            Comment


            • #7
              I took a picture of that area, and where I put a hatch just forward of the stove-lots of room there. Look at post 95, page 7 here:
              http://www.glasply.org/forum/technic...progress/page7
              My B744v is stbd side forward/under the v drive just outboard the stringer, the hull was somewhere between 5/8 and 3/4 from what I remember.

              Comment


              • #8
                Great. Thanks for the link to photo. That is exactly what I'm looking to do. Is that a standard plastic hatch that you customized for your floor or something different?
                I'd like to mount my transducer in the engine room where there is more space but Airmar says not to put a chirp in-hull there because it will be hard to keep cool.
                1986 Glasply 28' long cabin

                Comment


                • #9
                  I found a few matching teak hatches on ebay-I have 3 in the cabin. One is above the blank tank fittings, another is above the fresh water fittings and water pump. There are a ton of good used teak hatches with aluminum installation lips on ebay.

                  Comment


                  • #10
                    Originally posted by kisutch View Post
                    Does anybody know what the the expected hull thickness is in this area (forward of engine room bulkhead, port of centerline)?
                    As Mike said about 5/8 - 3/4 inch thick where I put my fairing block and thru hull transducer almost directly under the starboard hanging locker forward of head.
                    "Joint Venture" 1978 midcabin 28', twin 2017 Vortec roller cam "bullet proof" 383/6.3L full roller 350hp engines - You name it, I've either replaced it, restored it, rebuilt it, repainted it or repaired it. That's my job now that I'm retired.

                    Comment


                    • #11
                      I dont know exactly how far forward you plan to mount it, and I am sure you have this covered, but I think you would want to make sure that area is not out of the water when you are on step....just a thought..
                      1982 2580 "HI-BOY " IN 2 DEEP 5.7LX ALPHA

                      Comment


                      • #12
                        I don't think it will be too far forward. There is an old one that I assume was installed by factory in the same place as Bill's under that hanging locker. I may replace that thru-hull ducer with a wide beam some day but for now it makes a nice guide when sliding on the trailer. Anyway that one is ever further forward and was working ok until I removed the old SiTex unit. Thanks for the info about hull thickness, seems like I should be fine. Going to the boatyard this weekend to start some projects.
                        1986 Glasply 28' long cabin

                        Comment


                        • #13
                          Originally posted by Akgramps View Post
                          I dont know exactly how far forward you plan to mount it, and I am sure you have this covered, but I think you would want to make sure that area is not out of the water when you are on step....just a thought..
                          That is good advice as mine has come out of the water a couple of times when I tried WOT runs at speeds over 38-39mph.
                          "Joint Venture" 1978 midcabin 28', twin 2017 Vortec roller cam "bullet proof" 383/6.3L full roller 350hp engines - You name it, I've either replaced it, restored it, rebuilt it, repainted it or repaired it. That's my job now that I'm retired.

                          Comment


                          • #14
                            Well I wouldn't want it stop working at normal planing speeds (20-22mph) but my boat doesn't go quite that fast Bill. Also I'll be keeping a small Raytheon unit as backup that is connected to an older B44V thru hull in the engine compartment. It doesn't do crap for finding fish but it reads bottom very good and has temperature + speed wheel. I plan to move that unit on the flybridge dash and leave it on a page that has those three sensors in big font. But regardless, I don't expect to look for fish while running 30mph and I'm not running in the shallows at that speed either.
                            1986 Glasply 28' long cabin

                            Comment

                            Working...
                            X