Lowrance LMS-240 Problem--transducer?

Hi all;

just picked up a 2002 Starcraft Starcaster 1900 with a Lowrance LMS-240 depthfinder with a transom mount transducer. The depth reading has been erratic and now shows 0.0. The transducer is parrallel with the boat bottom. We even switched units to see if it worked with the front bow mount motor transducer but no luck. We are going to do a hard reset and software upgrade as well. The units GPS works fine as does the speed indicator. There seem to be two transducers on the transom. One has a thin gauge wire while one thick. As this is a 2002/3 model, could the second "transducer" be for speed and water temp?

Since the model isn't supported anymore, do you all think it would be worth it to by a replacement transducer if we can find one? Has sonar tech come a long way since 2002? Or maybe buy a new unit....

Too many questions I know but thanks!

Gary

Re: Lowrance LMS-240 Problem--transducer?

Understand Transducer do go bad. The crystal can crack when impact a sitck or something in the water.

My boat also has two transducer on the transom. My Lowrance unit is 192 KHZ and I have a 20 degree transducer for shallow water an a 8 degree transducer for salt water over 250 feet deep, good to about 650 feet.

I replace the 20 degree transducer one time because it got where one day it would work and the next day it would not. Or one hour it would work and the next hour it would not. My problem was easy to troubleshoot because the 8 degree transducer always worked. I also have a paddle wheel speed sensor.

Lowrance HDS units are a big step up in performance and price. They are low power so unlikely to damage any transducer. Still the reciever is so much stronger they see much deeper and more detail.

Re: Lowrance LMS-240 Problem--transducer?

Thank you Boatist;

I have enclosed pics of the two "transducers" on the transom. Could one be for temp/speed and the other for depth?

We have a front depthfinder with its own transducer mounted on the electric motor...

Thanks!

Re: Lowrance LMS-240 Problem--transducer?

Garynyc said:

Thank you Boatist;

I have enclosed pics of the two "transducers" on the transom. Could one be for temp/speed and the other for depth?

We have a front depthfinder with its own transducer mounted on the electric motor...

Thanks!

Click to expand...

Both look like transdcuers. Where do the cables connect?

Re: Lowrance LMS-240 Problem--transducer?

I agree both look like transducer. Most transducer today have the temperature sensor built in. Speed sensor usually a paddle wheel for Lowrance.
Older Lowrance Temperature sensors were a seperate little copper sensor.

If they are both Transducers then you will likely find one not plugged in unless you have an switch. If so try the other unit out on the water.

ON my unit I have two transducers and the 20 degree has a small wire. The 8 degree is a much larger transducer and has a larger wire.

Re: Lowrance LMS-240 Problem--transducer?

Thanks Boatist;

I cant trace the wire without removing the throttle assembly mount, which would result in a rat's nest of cables!

It might be a dual transducer setup? Or maybe one that went bad, and a second one was mounted leaving the first one...

The mystery continues

Any other folks want to chime in, please do!

Happy boating

G

Re: Lowrance LMS-240 Problem--transducer?

The LMS 240 only has one place to connect a transducer. My boat also has a lot of wires but with two people pretty easy to check wire. Just follow the wire as far as you can then have a second person with a light under the dash as you move the wire a little.

Re: Lowrance LMS-240 Problem--transducer?

Interestingly enough the connector for the sonar/data on the LMS has a thick and a thin gauge cable coming out of it. Maybe it's a dual transducer setup with varying cone angles?

Gary