Greasy question

Discussion in 'Materials' started by CDK, Nov 23, 2012.

  1. CDK
    Joined: Aug 2007
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    Location: Adriatic sea

    CDK retired engineer

    Twice a year my 3.5 tons trailer gets a quick dip in the sea. All bare metal parts like bearings and shafts are liberally coated with lithium grease.
    It was very disappointing to find all wheels and keel rollers blocked, clevis pins fused in their holes etc. Most of the grease is converted to soap or has disappeared completely. The rust is not brown but black, so there has been some interaction with the grease, but everything is still immobilized and must be taken apart and cleaned.

    My choice of grease was clearly wrong, but is there another lubricant on the market that stays put when immersed in seawater for an hour ?
     
  2. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    I dont know whats in this stuff. It drys to a waxy greasy film. It is incridible resistant to wash off. Perhaps find out what the secret ingredient is.

    http://www.crceurope.com/wwwcrc/tds/TCI3 SP400.PDF


    For delicate parts Lanogaurd..lanolin...is very effective. The spray is easy to use

    http://www.lanoguard.co.nz/products.html

    OMC Triplegaurd non corrosive grease is an old standby. I use it on the forward meter on my gavanized anchor chain to help with its self launch. After a season of hard use I can still detect reminantes of the grease. Very durable
     
  3. jehardiman
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    jehardiman Senior Member

  4. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    here's another one.

    http://parts.cat.com/cda/files/3056001/7/nehp6010.pdf

    Lithium soap greases aren't as good as calcium soap greases with regards to water. But now that you've got it on there, you need to get it ALL off before changing types. You may need to go to a stiffer grease as well. It doesn't sound like there's any reason not to use a stiff grease.
     
  5. Petros
    Joined: Oct 2007
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    Location: Arlington, WA-USA

    Petros Senior Member

    The blue molycoat grease I beleived is specifically marketed for boat trailers. IT is designed for repeated dunking into seawater. You might look to see if there is something similar available in your area.

    For the ultimate in durability however you will need to convert all the bearing to sealed bearings with stainless steel hardware. Our Japanese made cars or trucks all use sealed wheel bearings that will last about 200k-300k miles, while the old style grease packed wheel bearings still used on the American made trucks only last about 30k-40k miles.
     
  6. CDK
    Joined: Aug 2007
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    Location: Adriatic sea

    CDK retired engineer

    Thank you for the advice.

    CRC-400 spray is a product I am familiar with. It is a great rust inhibitor, but not a real lubricant. So I think blue Molycoat would be a good choice. I will look for a company on the mainland that services Caterpillars, local supply is limited to suntan lotion I'm afraid.

    Of course it would have been better to use stainless for all the moving parts, but I did not build the trailer for eternity. Besides, the many support wheels are Chinese ones with primitive needle bearings. I doubt if there are stainless ones on the market and if there are, they will cost 10 times more than the $12 I have paid for the current ones.
     

  7. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    Another product with very great resistance to salt water wash out is Tefgel. It is literally impossible to remove without solvent.

    http://www.tefgel.com/contain.php?param=tefgel_infor

    Unfortunately tefgel is very expensive so is only used on critical components.

    Again, what the magic ingredient is I dont know.

    Their other product Tuffgel is a lubricating "Thread lock " compound to replace loctite with using dissimilar metals and for galling prevention

    .
     
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