Corrosion on crevice of bearing

Discussion in 'Maintenance Bay' started by Desdemonaaa, Nov 9, 2019.

  1. Desdemonaaa

    Desdemonaaa Filing Flight Plan

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    Hello, was looking for info on corrosion found on a bearing. Is there a high chance of corrosion inside the crevice? And would it effect the parts ability to not fail or cause the bearing to pop out? The bearings are pressed in and are a flight critical parts. Thanks for any help on the topic 20190923_140344.jpg 20191009_164739.jpg
     
  2. Clip4

    Clip4 Final Approach

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    Looks like an old worn out bearing to me.
     
  3. Kenny Phillips

    Kenny Phillips Final Approach

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    Looks to be surface rust on the outside of a spherical bearing receiving hole. Can you see play in the bearing?
     
  4. Bell206

    Bell206 Final Approach

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    What area are you calling "corrosion" and the "crevice?" The gray/silver ball area is a coated area usually teflon or something similar and the brown/reddish ragged line next to the ball area appears to be the edge of the phenolic material or something similar that the coated ball area rides against within the link housing. But I really don't see any corrosion from these pics???
    Helicopter? What model?
     
    Last edited: Nov 10, 2019
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  5. PaulS

    PaulS Touchdown! Greaser!

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    It would really help to know what that bearing is on. But that looks like surface corrosion, I would watch it, but not be too concerned about it, depending on what it does.
     
  6. Dan Thomas

    Dan Thomas Final Approach

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    Looks fine to me. The brown stuff against the ball is likely the sintered bronze bearing itself, and the brown streak outside the bearing shell is too bright to be rust. Might be the adhesive that holds the bearing in the rod end.
     
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  7. Doc Holliday

    Doc Holliday Pattern Altitude

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    :rolleyes:
     
  8. JAWS

    JAWS Cleared for Takeoff

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    Looks more like dried out lube. Needs to be disassembled and the spherical ball cleaned and then felt by hand for wear and roughness. Any movement of the ball axially or radially is typically cause for replacement, but depends on the system and manual specifics.

    High cycle rodends and bearings will leave a tell tale black streak, which the pics above don't show. The bearings in the aft elevator bell crank on Navajos and Chieftans are like that. If you see black, time to replace.
     
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  9. Bell206

    Bell206 Final Approach

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    FYI: if that bearing is what I think it is, they are actually self-lubricating type bearings. No disassembly or lubrication possible. Actually if any lube is applied it reduces the life of the bearing. The "dried lube" you mention is more edge of the PTFE/phelolic material bonded to the interior of the link housing. The rod-ends you mention could be disassembled via the retaining rings and the actual ball-bearings relubed with grease. The ones pictured above have no ball-bearings, only a internally bonded bearing fabric on which the the coated ball rides on. Short of the bearing fabric migrating out of the link housing the only indicator to replace them is via axial/radial play. We'll see if the OP will respond with more info.
     
  10. James331

    James331 Ejection Handle Pulled

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    It should be all clear now to the OP with such a witty opine lol


    Side note, whenever I get corrosion in my crevices I normally take a shower :dunno:
     
  11. JAWS

    JAWS Cleared for Takeoff

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    Depends on the part number. P&WC has lubing procedures for their rod ends. Beech engine control rod ends are teflon and are supposed to see no lube. The teflon ones are identified with a white seal around the bearing. But there are so many variations and types.

    As stated, more info is needed to give a decent internet guess.
     
  12. skier

    skier Line Up and Wait

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    It does look like a self-lubricating PTFE liner. Note that they can have some play and still be perfectly acceptable. Some are even designed with clearance when new to minimize the initial breakaway torque.


    What’s the part number, manufacturer, and/or cage code listed on the OD?
     
  13. Bell206

    Bell206 Final Approach

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    Agree. But my guess the OPs pics are of helicopter flight control link bearings at the swashplate and not an engine control linkage. And considering they have data tags on them probably are tracked components.