Reference: Transducer Mounting - Moderated Discussion Areas

  ContinuousWave
  Whaler
  Moderated Discussion Areas
  ContinuousWave: Whaler Repairs/Mods
  Reference: Transducer Mounting

search | FAQ | profile | register | author help

Author Topic:   Reference: Transducer Mounting

jimh posted 06-02-2002 05:29 PM ET (US)
This message thread serves to collect comments and questions about thre REFERENCE article on Transducer mounting.
http://continuouswave.com/whaler/reference/sonarTransducer.html
tbyrne posted 06-04-2002 11:19 AM ET (US)
I was surprised about the article's suggestion of installing the transom mount transducer on the port side. I thought the conventional wisdom was to mount it on the starboard side at least 3" outside the prop's diameter to avoid the prop wash caused by the clockwise rotation of the prop. I guess whatever works, works.
Nice reference article - thanks!!
where2 posted 06-04-2002 01:05 PM ET (US)
On my own whaler, the previous owner had removed a transducer leaving me with holes that were plugged with screws and sealant. When I went to mount my own choice of transducer, I found that none of the holes lined up. So, I mounted a piece of 3/4" thick starboard to the transom, and mounted my transducer to it, rather than straight to the hull. If I ever change transducers again, I just redrill my starboard, and never have to worry whether the screws have loosened slightly, and might be leaking. If something strikes the transducer, it may pull the #8 screws out of the plastic, but not likely pull the #10 screws out of the transom.
jimh posted 06-04-2002 01:34 PM ET (US)
Generally the propeller turbulence occurs downstream of the SONAR transducer, unless you are going in reverse. (That might be the case if you back-troll a lot.)
The LOWRANCE skimmer transducer also has a friction-rachet mounting engagement. This allows the transducer to deflect upward if it strikes something.
Novice Dave posted 06-04-2002 04:57 PM ET (US)
I would like to minimize the holes in the transom. Is it practical to glue the starboard to the transom and then screw the transducer to the starboard? My transducer has the kick up release. What adhesive would be best to mount it for testing?
jimh posted 06-04-2002 05:06 PM ET (US)
If you want to test locations, mount the transducer mounting bracket to a 1x3 pine board, flush at one end of the board. Use a C-clamp to clamp the pine board to the transom and go for a test drive.
Ed Z posted 06-05-2002 04:03 PM ET (US)
Jim, What a great idea (pine board)... I just got a new x91 and was wondering how to install the transducer right on the first try... Have clamp, have board, will test...
Thanks for the idea...
where2 posted 06-06-2002 12:59 PM ET (US)
Difficult to "glue" starboard to anything. To "glue" two pieces of starboard together, you gotta buy the two part adhesive that starboard came up with. I simply made a piece of starboard to fit the screw holes from the previous owners rig, and screwed it down with those existing holes, which kept me from having to add more holes.
rsgwynn1 posted 06-18-2002 09:46 PM ET (US)
I'm not getting very good images on my new Garmin GPSMap 168. My installation tallies with the article and the photo, but I'm wondering if I should change the tilt on the transducer. Right now it's absolutely parallel with the line of the bottom of the hull--I checked it by holding a yardstick flat against the hull. Should I tilt out more to allow for the way the hull actually sits in the water?
Frank O posted 07-11-2006 12:55 AM ET (US)
I recently bought a 1995 21' Outrage that came with a Lowrance LMS-350A fishfinder. The unit has some problems that Lowrance is not willing to try to repair, so I've decided to upgrade to a Lowrance LCX-17M, which I ordered with a dual-frequency transducer.
The existing transducer and speed sensor are mounted on the transom with the wires routed up and over the transom. I'm keeping the boat in the water at a marina, and it's a pretty major pain to pull it out of the water. I don't mind putting on a wetsuit and small scuba tank to tackle the mounting with a hand drill and screwdriver, but I noticed in the reference article this thread is linked to that use of caulking is necessary to avoid water intrusion into the transom.
I'm looking at the wood-locating diagram that came with the manual for my boat, and though I could be misreading it, I'm not seeing any wood marked on the transom. Does anyone have any input on whether this is an issue for my year/model? Is it possible to do an acceptable transducer install with the boat in the water?

Jkcam posted 07-26-2006 04:20 PM ET (US)
Frank
Sadly, I believe that to do the job properly, you are going to have to pull the boat, or at least get the stern out of the water for a while. Even a beaching as the tide is almost low, would probably work. I would not be satisfied with an installation that might allow any water into the hull structure. Even if there is no wood in your selected location, I assume there is foam, and I would not want that foam absorbing any water.
I would not chance your proposed installation method even on a boat that is kept on either a lift or a trailer. I really think that you have to bite the bullet on this one.
Do you know anyone that has a lift that you could use for a couple of hours?
Best of luck.
jim
Link posted 07-26-2006 11:09 PM ET (US)
Jim, that is the simplest, greatest idea to find the correct mounting place for a transducer I have ever heard of. I now believe you do not have a Messiah complex, you are the Messiah. Too bad I mounted mine about 2 weeks ago directly to my transom so I'll only get to try your method if I mounted it wrong. Is there anyway you could add your advise to the reference section on your site, as that is probably where most of us look first.
tombro posted 07-27-2006 07:38 AM ET (US)
I've found over the years that any reading while running at speed is suspect, and likely bogus, due to the rearward tilt of the transducer while planing. I only trust sonar returns while slow trolling @ 3.5 knots or so.
bigjohn1 posted 07-27-2006 08:11 AM ET (US)
rsgwynn1, give that ducer another click or two down and it'll give you the returns you are seaking.

Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.

Author	Topic: Reference: Transducer Mounting
jimh	posted 06-02-2002 05:29 PM ET (US) This message thread serves to collect comments and questions about thre REFERENCE article on Transducer mounting. http://continuouswave.com/whaler/reference/sonarTransducer.html
tbyrne	posted 06-04-2002 11:19 AM ET (US) I was surprised about the article's suggestion of installing the transom mount transducer on the port side. I thought the conventional wisdom was to mount it on the starboard side at least 3" outside the prop's diameter to avoid the prop wash caused by the clockwise rotation of the prop. I guess whatever works, works. Nice reference article - thanks!!
where2	posted 06-04-2002 01:05 PM ET (US) On my own whaler, the previous owner had removed a transducer leaving me with holes that were plugged with screws and sealant. When I went to mount my own choice of transducer, I found that none of the holes lined up. So, I mounted a piece of 3/4" thick starboard to the transom, and mounted my transducer to it, rather than straight to the hull. If I ever change transducers again, I just redrill my starboard, and never have to worry whether the screws have loosened slightly, and might be leaking. If something strikes the transducer, it may pull the #8 screws out of the plastic, but not likely pull the #10 screws out of the transom.
jimh	posted 06-04-2002 01:34 PM ET (US) Generally the propeller turbulence occurs downstream of the SONAR transducer, unless you are going in reverse. (That might be the case if you back-troll a lot.) The LOWRANCE skimmer transducer also has a friction-rachet mounting engagement. This allows the transducer to deflect upward if it strikes something.
Novice Dave	posted 06-04-2002 04:57 PM ET (US) I would like to minimize the holes in the transom. Is it practical to glue the starboard to the transom and then screw the transducer to the starboard? My transducer has the kick up release. What adhesive would be best to mount it for testing?
jimh	posted 06-04-2002 05:06 PM ET (US) If you want to test locations, mount the transducer mounting bracket to a 1x3 pine board, flush at one end of the board. Use a C-clamp to clamp the pine board to the transom and go for a test drive.
Ed Z	posted 06-05-2002 04:03 PM ET (US) Jim, What a great idea (pine board)... I just got a new x91 and was wondering how to install the transducer right on the first try... Have clamp, have board, will test... Thanks for the idea...
where2	posted 06-06-2002 12:59 PM ET (US) Difficult to "glue" starboard to anything. To "glue" two pieces of starboard together, you gotta buy the two part adhesive that starboard came up with. I simply made a piece of starboard to fit the screw holes from the previous owners rig, and screwed it down with those existing holes, which kept me from having to add more holes.
rsgwynn1	posted 06-18-2002 09:46 PM ET (US) I'm not getting very good images on my new Garmin GPSMap 168. My installation tallies with the article and the photo, but I'm wondering if I should change the tilt on the transducer. Right now it's absolutely parallel with the line of the bottom of the hull--I checked it by holding a yardstick flat against the hull. Should I tilt out more to allow for the way the hull actually sits in the water?
Frank O	posted 07-11-2006 12:55 AM ET (US) I recently bought a 1995 21' Outrage that came with a Lowrance LMS-350A fishfinder. The unit has some problems that Lowrance is not willing to try to repair, so I've decided to upgrade to a Lowrance LCX-17M, which I ordered with a dual-frequency transducer. The existing transducer and speed sensor are mounted on the transom with the wires routed up and over the transom. I'm keeping the boat in the water at a marina, and it's a pretty major pain to pull it out of the water. I don't mind putting on a wetsuit and small scuba tank to tackle the mounting with a hand drill and screwdriver, but I noticed in the reference article this thread is linked to that use of caulking is necessary to avoid water intrusion into the transom. I'm looking at the wood-locating diagram that came with the manual for my boat, and though I could be misreading it, I'm not seeing any wood marked on the transom. Does anyone have any input on whether this is an issue for my year/model? Is it possible to do an acceptable transducer install with the boat in the water?
Jkcam	posted 07-26-2006 04:20 PM ET (US) Frank Sadly, I believe that to do the job properly, you are going to have to pull the boat, or at least get the stern out of the water for a while. Even a beaching as the tide is almost low, would probably work. I would not be satisfied with an installation that might allow any water into the hull structure. Even if there is no wood in your selected location, I assume there is foam, and I would not want that foam absorbing any water. I would not chance your proposed installation method even on a boat that is kept on either a lift or a trailer. I really think that you have to bite the bullet on this one. Do you know anyone that has a lift that you could use for a couple of hours? Best of luck. jim
Link	posted 07-26-2006 11:09 PM ET (US) Jim, that is the simplest, greatest idea to find the correct mounting place for a transducer I have ever heard of. I now believe you do not have a Messiah complex, you are the Messiah. Too bad I mounted mine about 2 weeks ago directly to my transom so I'll only get to try your method if I mounted it wrong. Is there anyway you could add your advise to the reference section on your site, as that is probably where most of us look first.
tombro	posted 07-27-2006 07:38 AM ET (US) I've found over the years that any reading while running at speed is suspect, and likely bogus, due to the rearward tilt of the transducer while planing. I only trust sonar returns while slow trolling @ 3.5 knots or so.
bigjohn1	posted 07-27-2006 08:11 AM ET (US) rsgwynn1, give that ducer another click or two down and it'll give you the returns you are seaking.