An Alternative to Castor Oil!

[catmand00]

I have a Clipper Echo sounder with an in-hull installation (sensor is within the hull in an oil filled tube).
To date I have always used castor oil as the medium between the transducer & the inside of the hull.
My oil is contaminated so I wish to replace it. Easy? No!
Apparently, castor oil has been declared dangerous to human constitutions & off limits so is no longer available so I would appreciate any advice on a suitable substitute oil – linseed, olive etc.

All thoghts gratefully received.

[rover88]

Mineral oil, but most manufactures recommend antifreeze.

[bruce smith]

Castor Oil has been declared dangerous to human constitutions?
Off topic a tad here, but I have heeled numerous skin problems (lipoma) and a broken leg with castor oil.
Not for internal use, but castor oil is one of the strongest medicines in the natural heeling world.

[Roy M]

Originally Posted by bruce smith

Not for internal use, but castor oil is one of the strongest medicines in the natural heeling world.

That, pretty much, excludes use aboard multihulls. But then, I just look out the portlight in the head and watch the waves streaking past between the hulls. That really loosens things up.