Sealant Advice

[NahanniV]

I am preparing to re-install my rudder tube (and re-built rudder).

The seal at the thru-hull had failed; Luckily the fitting is only a few inches below the waterline and the compartment where it enters the hull has a water-tight bulkhead.

The failure seems to be due to hydraulic leaks from the steering gear. While on the hard the seal that failed had a pool of hydraulic fluid around it and some was seeping through to the outside of the hull.

The original sealant seems to be clear silicone; Most of the fittings on the boat are bedded with this and it seems to have worked well.

What I am worried about is that the fiberglass around the thru-hull seems to be saturated with oil. I scraped off the silicone, washed, de-greased and wet sanded the area. But, there still seems to be oil in the glass.

Any advice or ideas on products or procedures to use would be appreciated.

Cheers,
John.