NASA DEPTH SOUNDER - WHAT TYPE OF OIL?

Scotty_Tradewind

Scotty_Tradewind

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The oil in my NASA depth sounder transducer is low, and I only get reliable depth reading when upright, otherwise 'OUT'.

I assume all I deed to do is top up the oil without getting bubbles in it?

What type of oil should I top it up with please without having to buy a complete kit, and who sells it?
ta
Scotty
 
Castor oil was certainly the oil recommended by Seafarer. The Nasa instruction manuals just talk of an "In hull mounting kit" but dont say what the oil is.

I think Id try to remove the old oil rather than mix two different ones but I doubt if it would really matter.

If the reservoir is leaking then it would be sensible to clean it all up thoroughly and patch up the leak.

In reality any liquid which is stable, does not react with the hull, mounting or transducer, is not volatile, does nor freeze, smell or impose any other threat if it leaks would do.
 
You can almost any oil you like, I had Johnsons baby oil in one of my early boats with never a problem.

You are only adding a liquid to ensure no air is under the tip if the transducer.

Oil bath transducers give a more accurate depth reading when heeled in shallow water, not a problem in deeper water as the beam has enough distance to widen over a larger area so the signal will bounce back.

Avagoodweekend......
 
If you bought it in the chemists at Tescos in Henley on Thames, then I had the last one.
I will do a test on the little of whats in the bottom of my tube and see if it is caster oil, probably by taste or smell, eugh!, and if the same I will add. Otherwise, it will mean drying out thoroughly with tissues and I'll start with the caster oil from scratch.
I definatly have a very small leak, so to find it and try to plug that temporarily for the rest of the season with blue tack or chewing gum seems a possibility. Thankfully the transducer sits in its own little section in the bilge up front with a small cover and so it can leak away slowly causing no problem in the short term.
Thanks to you all for your input, I especially like the ideas of salt water and engine oil being two mediums easily at hand.
Any more advice gratefully accepted,
oh, I have noticed that the transducer ticks away merrily and I read elsewhere that some do and some don't. I assume that it will be quieter when there is a little more oil or whatever covering it?
ta, Scotty
 
use a tube of KY, that may come in handy in an emergency too !

p.s. no air bubbles, else whatever you can lay your hands on, i can sell you some special shark oil, excelent for the tropics /forums/images/graemlins/laugh.gif

p.p.s. LOL a zillion posts on this already /forums/images/graemlins/laugh.gif
 
I was trawling the tinternet to see which oil to use on mine, went for engine oil was it was close to hand. Seems to work with the boat on the drive, hopefully it will work on the water !

Cheers

Stu
 
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