Annual Seacock


Reprinted with permission of

Spartan Marine Hardware
340 Robinhood Road
Georgetown, ME 04548


Spartan Marine stocks Seacock Grease,
Seacock Lapping Compound as well as a
complete Seacock Maintenance Kit.


Anatomy of a seacock


1. With the boat out of the water, hold the handle and using a wrench, remove the lock nut, adjusting nut and washer.

2. Remove the tapered plug from the seacock body.

3. Thoroughly clean the tapered plug and the inside of the seacock body with a solvent that will cut the old grease.

4. Put a small amount of seacock lapping compound on the tapered plug.

5. Insert the tapered plug into the seacock body and work it back and forth a few times using the handle and moderate hand pressure.

6. Remove the plug from the body and clean both the inside of the body and the plug thoroughly. DO NOT leave any of the lapping compound on these surfaces.

7. Apply a liberal coat of seacock grease to the plug and the inside of the body.

8. Place the plug back in the body and put the washer onto the threaded portion. BE SURE to orient the flat portion of the washer onto the flat of the shaft.

9. Install the adjustment nut and tighten just snug enough that the plug will not rotate due to engine vibration.

10. Once properly adjusted, install the lock nut and tighten it while holding the adjustment nut with a second wrench.


Winterizing a tapered plug seacock

If the boat is left in the water, close the seacock and then remove the two drain screws from the seacock body to drain the water from the cavity in the tapered plug. Failure to do this can cause the seacock body to split in freezing conditions and could result in sinking of the boat.

If the boat is hauled out for the winter, just place the seacock in the open position and any water will drain out thus preventing any damage in freezing temperatures.



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