Winterizing sonar transducer

I've heard that the transducer for the sonar sits in liquid and should be winterized with antifreeze or mineral oil. Where is it located on a 2013 R25sc? How do I access it? We can get temperatures down to -40 here in winter and I'd like to be sure nothing freezes.
Thanks

I just had to fill mine because of a leak. My dealer told me they are filled with the same anti-freeze that is used for winterizing the water system. Worked like a charm. Two birds, one stone. I cannot help you with it location, sorry.

On my 2010 25SC it is located on the starboard side near the stern. Access is through the center cockpit seat, remove the internal portion of the center seat and you should see it. You just about have to do a head stand to reach it. Now it depends how the factory installed it. Mine was epoxied to the hull, If it was epoxied there will not be any fluid. Mine had come loose so I installed the reservoir cup. If you have the cup it takes 2.4 oz of RV Antifreeze year round.
Here's the manual for the transducer http://www.airmar.com/uploads/InstallGu ... 217-01.pdf

Thanks for that information. I found the transducer, and was able to do the headstand and reach it to confirm it is the AIRMAR P79. When I have more time I will open it up and check the fluid level, but for now it is working so I can assume it has the RV antifreeze in it and I don't have to worry about winterizing it. Thanks for the peace of mind!

If your depth finder is working there is no need to open it up and do anything. If for some reason it looses antifreeze (mine did because it was installed without the O-ring gasket) it will give you flashing readings, totally inaccurate readings, and eventually quit working. I found a turkey baster was the best way to fill it because it is difficult to reach. If you overfill, it just spills over the cup when you re-install the transducer. Paper towel cleans up the spill. I used -100 degree non-toxic antifreeze at the recommendation of my dealer.

The manufacturer warns that the transducer could overheat and fail if operated with no liquid; which is why I may still open it up to check, just in case, even though it is still working. It sounds as if it will act up and give random problems if it goes dry, long before it actually fails? Is that normally the case?
Since the transducer is always in its own liquid (if the cup is full), then I assume it is safe to operate the sonar when the boat is on the trailer? I would like to be able to play with and learn the NAV system on the trailer without worrying about turning off the sonar.