Navman 100 Series Instruments

[littleelse]

Hello

We installed Navman instruments over ten years ago, a Multi M100 (speed and depth), a wind instrument and a repeater. They all worked really well until last year, when the speed stopped reading at all! Everything else works fine, and the speed reads 0.00 all the time, not -.--, which tells me the cable is fine. We have removed the unit and cleaned it, while the boat was on the hard this spring, twirled it with a finger (as you do) and checked that it was reading knots, and it was - put the boat back in the water - zippo speed!

Question - has the through-hull bit of kit failed, and if so, where will I find a compatible unit - ideally a spare transducer complete with Fuji cable - as nobody now makes this model, and I don't know if the 3100 series transducer would be compatible with the rest of the Navman instruments.

Any suggestions or comments please, I'd be grateful.

[GordMay]

Greetings and welcome aboard the CF, littleelse.

Excerpted from ➥ http://www.cruisersforum.com/forums/...ent-15440.html

“... 1) With 12VDC Power and Instrument “On”; remove the coax cable from the connector found on the rear of the speed instrument (display).

Bend a paper clip into a U shape and place one end of the paper clip into the center hole of the connector (signal) on the rear of the unit.
With the other end of the paper clip tap on the outside (ground shield) of the same connector (essentially shorting the inside pin to the outside collar) rapidly while watching the display.

If the speed increases as you tap, then the instrument is capable of producing a speed. You should be able to see about a 5 knot speed with rapid tapping.

If not; you will need to send the knot meter in for service ...”

[Jim Cate]

G'Day Littleelse, and welcome to CF,

If the instrument responds normally when you spin the paddlewheel with your finger, then there is nothing wrong with it electrically. Rather, it must be something stopping the paddlewheel from turning with the flow of water along the hull.


One thing to check is that there isn't any growth inside the through hull fitting that the transducer fits into. It is possible that such growth is squeezing the sides of the
assembly in such a way as to jam the wheel. Also look for anything that could be getting into the wheel on the outside of the hull. I've had soft growth forward of the transducer that trailed back and jammed the wheel under way, but wasn't obvious when I inspected it in the water at rest.

Getting parts for NavMan (ex Standard Horizon) instruments is nearly impossible... I have an intermittent wind angle transducer that I'd like to replace, but they don't seem to be available now. Grrrr.

Good luck...

Jim

[littleelse]

Thanks Gord, and Jim and Ann, I'll check out your suggestions! I like solutions that use really cost-free items like paper-clips! This has been quite a weedy year in Scottish waters for our boat - the rudder currently has a vertical green pelmet on it! (Thinks, must get the brush sometime and clean it off) So the question of whether the water is reaching the paddle is a good one.

[alih]

Hope your problem with the Navman worked out.

Am wondering if anyone can tell me where I can get a replacement paddle wheel for a Navman Multi M100?