The ice has finally gone out of our inlet here at Base Camp and we are getting Morgan’s Cloud ready for launching. Here’s a neat tip that my friend Bob (a fellow charter member of the anal retentive boat owner’s club) taught me.
Why You Should
Metal seacocks should be lubricated every year before launching. If you don’t grease them they will eventually seize up, and since Mr Murphy is always in charge at sea, you will find that state of affairs when you try to close the seacock after a large water hose ruptures.
It’s even worth lubricating the relatively new “maintenance-free” seacocks—those with teflon mating surfaces. Why? Well teflon (PTFE) is also manufactured with oil imbedded as an additional lubricant, but that’s not what they use for seacocks. The point being that if teflon is good, greased teflon is better.
Even if your seacocks don’t seize up, if you don’t lubricate them they will eventually stiffen up so that when working them open and closed you will be putting a huge load on the mating surfaces where the actuating shaft (that connects to the handle) and the ball bear on each other. Eventually, slop will develop in this area and the ball won’t fully close-off the seacock—a scary problem since we might assume a seacock is closed to the deep blue when, in fact, it’s not.
As an aside, the seacocks on a lot of older boats have this problem, and so we should all check for it regularly and look carefully. We have had to replace two seacocks on Morgan’s Cloud for just this reason, that looked and worked fine on casual inspection.
The Hard Way(s)
OK, now we know we have to lubricate, but how exactly do we go about doing that?
Sure we could pull the hoses off to lubricate the ball by squirting a spray lubricant in with the seacock closed…lots of luck with that. Ever tried getting a large hose off a tail pipe it’s been clamped to for even just a year? Good way to burst a blood vessel.
Or we could squirt some spray lubricant in from outside, but it will drip all over our boat’s newly painted bottom.
Worse still, some spray lubricants contain solvents that will dissolve bottom paint. How do I know this? Well, it wasn’t pretty, and resulted in a lot of sanding and repainting.
And anyway, spray lubricant won’t last long.
Some seacocks have a plug you can remove—ostensibly there for draining, which is, if you think about it, a pretty useless “feature” for most of us since said seacock will drain when you open it. But you could temporarily replace said plug with a zirk fitting and use a grease gun. What a hassle.
The Easy Way
Or you could do it Bob’s-Easy-Way:
- Close all the seacocks.
- Paint the balls from outside the boat with Lubriplate 130-AA grease, which lasts great underwater, using an acid brush (see photo above).
- Work the seacock through its entire travel a few times.
- Repeat as necessary.
The above process is faster and easier with two people, one working the seacock from inside the boat and the other outside the boat painting the balls.
One caveat: If you have the old fashioned seacocks with the tapered cylinders, you should probably completely disassemble them for service every three years or so since they depend on a clean well-greased mating surface on the cylinder and casing to remain waterproof. Having said that, Bob’s trick will work fine for the interim years.
Thank you, Bob.
Comments
Do you have any cool pre-launch maintenance tips? ‘Tis the season, at least for us northern residents. Please leave a comment.
Hi John,
Good suggestions in part because it is almost exactly what we do. The difference is Ginger sprays our grease in from the bottom while I work the seacock, the former being what you advise against. I believe in the US we were able to find a spray Lubriplate, but over on this side of the pond I have settled for CRC White Lithium Grease which has seemed to work fine. It does dribble a bit so I only do the spray after the bottom paint is done and dry. The dribble has not affected my bottom paint (usually Micron) in any noticeable way. In any case, I see no reason that spray grease, well worked in to a moved back & forth seacock, should not last as long as a brushed on grease, similarly worked in (maybe spray Luibriplate is less thick?). That said, brushing sounds likely to be more thorough and less messy with over-spray.
My best, Dick Stevenson, s/v Alchemy
Hi Dick,
I based my distrust of the longevity of spray lubricants on a combination of experience (that’s what I used to do) and the testing by Maxprop who have found that Lubriplate 130AA is the only grease that lasts in their propellers without washing out.
Having said that, of course there maybe other greases (including sprays) that I and Maxprop have not tried that work well.
Doesn’t this just lubricate the half that’s exposed to the outside while leaving the inside half unlubricated?
That’s what the back-and-forth is for. The action puts the greasy part of the ball on the inside mating surface, and some will get on the other side with enough action.
I also use lithium grease. I will switch to Lubriplate for salt water as it appears more tenacious.
Hi Todd,
As Marc says, working the seacock several times seems to distribute the grease well. If the seacock has not been lubricated for years, it’s probably worth painting the ball several times and working it half a dozen times between each painting.
Marc, it might just be the model of Groco seacock that I have but mine only allow 90 degrees of motion on the handle so there’s virtually no overlap.
I’ve also not figured out a better solution than painting the outside with grease so that’s what I do too.
Hi Todd,
That got me thinking, so I just sketched it out and with 90 deg of handle movement there is about a 60 degrees (rough guess) of overlap of the two sides of the ball. I think that should be enough to distribute the grease as long as you work it enough.
I also have two of the new Grocos (the replacements mentioned in the post) and they seem to benefit from this treatment in that they get easier to operate after it and my old Grocos (no teflon) get way easier.
Hi Again Todd,
Just looked my diagram again after I had had by morning tea (always smartens me up) and realized I was wrong, the overlap is probably only 20 degrees or so, so your worry is at least partly justified.
See Eric’s comment for a good solution.
On some seacocks, you can actually get them to turn a full 360 if you remove the handle and use an adjustable wrench instead. If you look at how they are put together, the stops are usually built into the handle.
Eric
Eric, great suggestion! My solution has been to fully open and then close the handle ever so slightly. I then reach a brush up to get some grease on the leading upper edge (the inaccessible side) of the ball in the hopes that the closing action will spread the grease on that side.
However, it’s always bugged me a little knowing one side is properly greased and the other is very slightly greased (but not enough to remove the hose from every seacock). You’re absolutely right that removing the handle will allow a full range of motion to do the entire job from the outside of the boat!
Hi Eric and Todd,
Thanks for sorting that between you. It’s very rare these days that I put up a post that you members don’t improve on in the comments.
I suggest using Silicone Grease.
I’ve always used the Molykote brand (others may be just as good) which is extremely water resistant and tenacious. It’s also useful for O-rings, sail slides and all sorts of other things.
Good stuff to have on board.
I developed a corollary to my law: “If anything can go wrong, it already has: you just don’t know about it yet.”
Westbrook Murphy
So true!