Lubricating Plastic Through-Hull Valves

[SailDan]

Getting ready to launch this week and discovered that my plastic thru-hull valve for the engine fresh water intake is extremely stiff and difficult to open & close.
Questions:
(1) What is the best method of lubricating these plastic valves.
(2) What type lubricant / product should I use?

The boat is still on the hard and I can still pour some liquid product into the intake from the inside by removing the "screen" filter. I've had suggestions of vegetable oil, WD-40 spray, baby oil, etc.
Dan

[dave davis]

If you have the standard thru hull valve made by Forespar and sold by Marelon, they recommend "water pump grease or even vegetable oil" At one time they use to give you " Lanocote" tube when you bought the valve.  They may still handle Lanocote at WMP. They also recomend to actuate the handle on a regular scedule. I open or close the valve every time I leave the boat. There has been many major Tech notes about the care and feeding of these very important valves.

[Brad "Captivated" # 1285]

Since your boat is still on land. Take a minute to inspect the thru hull from the outside of the hull to make sure that there isn't any growth on it or in it. Just use a flashlight to inspect it. Sometimes zebra muscles or other creatures like to make a home in the holes.

[Roc]

I get Lanocote and a small brush.  Close the seacock so the ball is in view from under the boat.  Slop Lanocote on the ball, then go back in the boat and work the handle several times.  I do this to all the seacocks before launch.

Roc-

[SailDan]

Thanks to all for the recommendations...
Dan