Transducer Help

[Gimpy]

I have installed my Humminbird system in my boat. I tested the unit and the system prior to attaching the transducer in the hull of the boat.
Everything worked well in the test then after the epoxy dried my unit now thinks I am never more shallow than 900 feet.

When I attached the unit I followed the instructions and gave the unit a slight twist to expel the air but I can't think of anything else that might be causing the problem.

Any ideas would be greatly appreciated.

[kopper_bass]

Gimpy,
I noticed you didnt get any help on this topic. bummer!

I am assuming from your post that what you did was install a transducer on the inside of your boat, and epoxied it to the bottom in the bilge area? Please confirm.

You say that you tested it before hand and it worked, what do you mean? Dont know of too many ways to pre-test shooting thru the hull, so more information on what you did would be helpful.

Now, when you say you did everything the instructions say, what does that mean? Give us more details so we can know what you did and what you maybe didnt do to help you. For example:

1) did you cut down the fiberglass in the bilge so that the transducer is nested down into it? how far did you cut down?

2) did you let the epoxy setup slightly before applying and try to get all the air bubbles out?

3) did you put epoxy down first, then install the transducer, or push the transducer down to the floor and epoxy around it?

The most likely result of what you have done is that you either didnt clear enough fiberglass away so that the transducer can shoot thru the hull, or you got an air gap in between the hull and the transducer causing a false reading. these are the 2 most common problems with installing a shoot thru transducer.

One quick thing to try as a test, before you go pulling it all up.
take a soup or tuna can and cut both ends out. place it around the transducer and try to seal it to the floor of the boat as best you can with some playdoe or putty. Now, get some heavy cooking oil (olive, or vegatable) and pour it in the can, filling in around the transducer. you dont need to fill it all the way up just enough to cover all the epoxy areas. this will hopefully seep in and fill any air pockets or holes you might have there. Now take it on the water and see if you get a good reading with the meter. this would confirm an air pocket that has an air vent. after cleaning up the oil mess, you could then add some super thin adhesive to do the same as the oil and possibly fix it without tearing up the whole thing.

Give some more info and maybe we can also help you further.

Good Luck,

Kopper_Bass

[ash]

Gimpy,

I feel you I did everything by the book on my Lowrance install - Sanded down the area, cleaned it. Careful with the epoxy, worked it in slowly, etc...

come to find out my transducer actually had a small pin hole on the bottom that was shorting it out. Went to CC and they helped me up, hooked me up best $$ spent.

[Gimpy]

Thank you for the options I will give them a try.
The process I took was to sand down a bit of the hull in the bilge area ensuring everything was dry and smooth.
I used the recommended epoxy, throughly mixed it to try and work out the air bubbles.
I placed a bit on the hull of the boat and some against the transducer.
I then pressed the two together giving it a slight twist to work out some of the air bubbles.

When I tested the system prior to epoxying the transducer in place was to check the transducer in a bucket of water after I had run the lines to the dash to ensure I had no nicks / shorts in the line.
After launching the boat and pressing the transducer to the hull of the boat I was getting reading at the unit (taking the passengers word since I was head down in the bilge area.

Thank you for the suggestions on the oil. I will try that this weekend.

[BassinDan]

this is for lowrance but should work on other shoot through installs as well


** NOTE **
IF YOU LOSE YOUR SONAR AT HIGH SPEED, THIS IS ALMOST AN EXCLUSIVE INDICATION OF IMPROPER TRANSDUCER INSTALLATION. BY FOLLOWING THE INSTRUCTIONS BELOW, YOU WILL GREATLY DECREASE THE CHANCES OF IMPROPER PERFORMANCE AND PREMATURE TRANSDUCER WEAR.


1) Make sure to choose the APPROPRIATE transducer for the application. DO NOT USE A DUAL FREQUENCY TRANSDUCER TO SHOOT THROUGH THE HULL! The 50khz side of a dual frequency transducer will not shoot through. The 200khz side is also too small to provide good quality returns in shallow water. This includes salt water!
2) Find a smooth spot on the bottom of your hull to shoot through. DO NOT SHOOT THROUGH THE HULL IN-LINE WITH OR THROUGH STRAKES. THIS INCLUDES THE KEEL! This WILL result in the loss of bottom at high speeds due to cavitation. You can test the hull for the “sweet spotâ€