NASA Target 2 Cruiser Depth Gauge Problems

[davidpbo]

My depth gauge a NASA Target 2 Cruiser Depth gauge is causing me problems. We are cruising the Clyde, its scale goes to 99m, if we are in deeper water than that it throws up erroneous readings of very shallow depths e.g. 0.7M. It is disconcerting especially if a low water alarm is set.

Last year it was a contributing factor in us breaking the rudder because it had been happening on a fairly regular basis.

The shallow water alarm went off when we were some distance from the shore we did not react quite as quickly as we might have done in lifting the rudder and yes, there was a charted but unmarked underwater spit.

Does anyone else have this depth sounder and do you have this problem?

For me it would be far better if it gave an indication that it was out of range like my old one used to rather than a totally erroneous reading.. I know it is a cheap unit unit but it should be fit for purpose.

I have tried adjusting the sensitivity.

When I replaced to he gauge I did not replace the sounder. We were on Windermere at the time and it gave no indication that it was m not working correctly as maximum depth is not greater than 99M.

If other people do not have a problem with this model and cruise waters with greater than 99M depth I will maybe swap it.

Also, what oil is used in the the tube?
It is not through hull fitted so relatively straight forward to replace. Just fine consuming. I will check the oil level first.

 

[MikeCC]

Use castor or vegetable oil, not a mineral oil. Or alternatively, antifreeze.

No suggestions for depth readings but I'd be happy it was more accurate at shallow depths.

 

[davidpbo]

I changed the transducer for the one that came with the depth gauge, I had been using the old transducer from my previous NASA (Different model) depth gauge.

There was no appreciable difference in performance.

Changed the oil (Certainly it was 20years old and probably much more), and made sure the head was not touching the bottom of the tube. I now seem to be getting much more user friendly and consistent readings. Above 99M depth it just reads 99 which is fine by me, and I am getting more consistent readings in 50+ meters of water which I was not before.

Only done one trip across Loch Fyne, but looking good.

 

[Refueler]

The tube can have water ... castor oil ..... veg oil ..... or you can even pour epoxy in and glue the head to the hull - just make sure no air bubbles.