Marelon Thru Hull Valves

[Captain Kirk]

This is not new stuff but.....

There is a recent thread on the C34 message board regarding failure of a Marelon valve. The C34 owner, while underway, for some reason decided to remove the screw that holds in place the valve handle and the O-ring that together keep water out. With the handle out, the O-ring popped out, resulting in a lot water coming into the boat.

This happened to me years ago on our C320 when I was opening a thru-hull, the screw came out and the handle pulled out, water came in at a pretty good rate. In my case these valves were very hard to open/close and the strain on this handle was too much, it broke loose. ( Its a tiny little screw ) It is very concerning when you have a valve you cannot close that is leaking/gushing at a gal/min. I wrapped the valve with a rag, that was close at hand then wrapped that with rescue tape. I alerted the CG and headed to the nearest marina, about 3 hours away. The bilge pump kept up. All worked out fine, I located an O-ring and had a screw on board that solved the problem. ( I put in a new Marelon valve at my next haul-out)

I learned that these valves need to be lubed with Marelube. This is a key to reducing strain on the handle and keeping the valves working smoothly and easily. Its also wise to check that the screws are all snugged down.

Just some thoughts.

[russp]

Totally concur about using Marelon lube on the through hulls. I had routinely stroked the thru hulls on Avalon but they were getting stiffer and stiffer and I was sure sooner or later a handle would just break off so I got some Marelon lube, and while hauled blocked the outlets in succession, poured lube down the inlet either directly or down a sink outlet (whichever was easier) and stroked the valves many times while full of lube. Has made a huge difference, they all stroke with a comfortable level of force now, and they are 19 years old and apparently in otherwise perfect condition.