Grease for marine davit crane

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I'm installing a pipe davit behind a concrete seawall and am trying to decide what sort of grease to use. It is custom built so there are no manufacturer recommendations to reference. (The machine shop has made many similar systems, but didn't provide much guidance.)

The davit is constructed of 4" diameter stainless steel pipe, and consists of a a ground sleeve and a long bent pipe which rotates inside the ground sleeve. The base of the ground sleeve is welded closed, and the davit rotates within the ground sleeve on a stainless steel hitch ball which is welded to the bottom of the bent pipe. There are no bearings. The diameter of the ground sleeve is approximately 1/8" greater than the davit pipe, and there is a zerk fitting on the ground sleeve for renewing the grease. I plan to liberally grease the bottom and sides of the ground sleeve before inserting the davit pipe.

Any suggestions on what type of grease to use? One option is marine trailer wheel bearing grease, but my application isn't subject to the same high speed rotation as wheel bearings.
 
Marine wheel bearing grease would be my preference
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Is it exposed to direct sunlight? If so, the grease will soften and flow during the day. Over time it will loose some solvents, so it will stiffen. The best way to avoid that is to inject one shot of oil into the grease fitting every 90 days or so. Not much, just enough to replenish what evaporates.
 
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Simple enough. About 2/3 of the ground sleeve base is below grade embedded in concrete; the other 1/3 is above ground exposed to sunlight.

I'm thinking of using Lubrimatic Marine Grease (calcium sulfonate complex thickener), unless someone has a better suggestion.

Thanks for the advice.
 
Whatever marine grease that is easy to find and a decent price.
I use Mystik JT6 ... a waterproof all purpose (Green tube at TSC).
Sounds like you can find Lubrimatic around there ...
 
If your davit crane has no seal to keep dirt and water from entering the bottom sleeve, think about installing something like this, without the bottom clamp:

fc-pipe-sleeves-main.jpg
 
Good suggestion, though not needed in my case. There is in fact a collar welded onto the davit pole which overlaps the top of the bottom sleeve by a few inches, for this very purpose. It's possible at extreme high tides in windy conditions that a little water could find its way up into the small gap between the collar and the bottom sleeve, but I'm hoping to keep it packed with enough grease to keep water and sand from entering the bottom sleeve. Once it is all assembled, if it looks like anything could get in there, I may use a a rubber ring or even wraps of silicone tape to reduced the exposed gap.
 
Any marine grease that is extremely washout resistant should work well here. Even some of the general purpose greases that are not specifically a marine grease would work. Some examples are Omni Green Grease and Mystik JT6. Both are super sticky and wash out resistant. As for marine grease, I like Lucas Marine Grease but the Lubrimatic Marine grease you suggested should work fine also.
 
I also like that JT-6 (green tube) is colorless - when you grease something to "purge" - I like to see if the grease has picked up any color ...
 
The boat trailer wheel bearing is the easiest available grease that will do a very good job. Look for aluminum complex base. Sta-Lube Marine grease is one.

Check for a Schaeffer rep in your area that will sell you a few tubes of any of the greases with the aluminum complex base and the moly additive. The aluminum complex base is the most waterproof. You will get water into it. I'd plan on pulling the davit yearly, sucking the water and assorted dirt & slop out, wiping clean, regreasing, and put the davit back in. The moly is the best for a low speed, heavily loaded moving joint.
 
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