Wind direction fail in old Autohelm ST 50 plus

[Chuck Cohen]

We have a Hunter 450 Passsge 1997 Model. We bought it new. The original Autohelm ST 50 PLUS wind instrument is still in there and has always worked reliably. Now, however, the wind direction needle doesn’t move. Stays at 60° even though the windvane up top seems to be totally functional. The wind speed is working fine. So, I guess the question is if the transducer is history or what. Thanks much.

Chuck Cohen

 

[Rich Stidger]

The easiest way to identify the fault is with substitution. Do you know anyone else who has the same ST50 instrument that you could borrow to try? Conversely you could swap the masthead unit for one that is known to work. Again you need someone that can loan you one.
Maybe a RayMarine dealer near you might have either of these units to loan you with your promise to purchase whatever has failed?
Before getting too far into the T/S process of measuring the masthead signals (see below) you should definitely check that the cables are securely connected to the instrument head inside the console. Unplug and re-plug the cables. Cleaning the connector contact with a good cleaner like "DeOxit D5" can only help.
Failing that, look at the attached document. Starting on page 15 is a procedure for testing the masthead unit independently.

 

[Chuck Cohen]

Thank you. I’ll look thru all this and talk with our mechanic.

 

[Terry Cox]

Hi Chuck, our original 1991 ST-50 still works quite well. It will go to sleep, but rarely. Usually will wake up after a few minutes. Autohelm will do the same, but wakes up when I cycle the breaker switch. Try that and see if it makes a difference. Just like my dang body that does not work like it used to.

 

[MitchM]

check their web site. as i recall there are some pretty simple electronic recalibrations you can try before replacing the whole thing. mine started to only read one direction of wind, it was easily fixed with a simple adjustment i found on line.

 

[capta]

Our ST-60 is about as cantankerous as a wino without a bottle. For a year and a half, it would fail on the port tack, sometimes coming back after flipping the breaker a time or two, sometimes not. So we purchased a new masthead transducer and it hasn't failed since the part arrived on the boat, even though the new part is still in the box.
However, if it is just the direction and not the speed as well, then I'd be looking more at the meter (loose wire) than the transducer, though a loose wire where they come out of the mast and connect into the system would be my second choice.