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Steve Lusardi Steve Lusardi is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 430
Default Replacing Compass Fluid

Sherwin,
You need to be very careful. Every manufacturer uses different fluids. The
one they use depends on the displacement and mass of the suspended unit.
Very often the fluid is a blend of different fluids to get the specific
gravity exactly correct for minimum load on the bearings. It is wise to call
the manufacturer and ask first. They are usually very helpful, but be
prepared for some significant cost. I had to refloat a Sperry Mk 47 Gyro
Compass which was suspended by a blend of Halocarbon 6.3 and Dow Corning DC
200. The compass takes about 2 liters. The HC 6.3 was $288 per liter and the
DC 200 was $200 for 3ml. The correct procedure is to weigh the gyrosphere or
in your case the rose assembly very accurately, then measure its exact
displacement in a calibrated vessel, then blend the fluids so that same
amount of fluid weighs exactly the same as the rose. If you get it wrong,
the rose sticks and the compass will be very inaccurate. Good luck.
Steve

"sherwindu" wrote in message
...
Can I replace some lost fluid in my Ritche Helmsman Compass myself? I
stupidly
opened up the wrong screws and let some leak out.

Sherwin D.