Engine Corrosion

Discussion in 'Flight Following' started by Ryanb, Feb 25, 2020.

  1. Tom-D

    Tom-D Taxi to Parking PoA Supporter

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    99% of engine corrosion, is no problem. it will poilish out.

    It's when the owner panics we will see major problems.
     
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  2. MarkH

    MarkH Pre-takeoff checklist

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    Not to take the tread too far off topic, but what are the regulations about overboring a certificated airplane? I was under the impression that oversize pistons, rings, and bearings were not allowed.
     
  3. Snowmass

    Snowmass Pre-takeoff checklist

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    The way to settle the corrosive effects of engine running and atmospheric moisture is for a scientific experiment say by a university engineering department. How about as a subject for a doctoral thesis. Am I the only one that gets tired of eternal unproven blah, blah?
     
  4. asicer

    asicer En-Route

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    For that to happen, first there has to be grant money...
     
  5. Dan Thomas

    Dan Thomas Final Approach

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    Do we need to have a university engineering student do a research project on running an engine out of oil before we can be sure that the engine actually seizes up?

    It's experience that tells us so much. My experience in repeatedly finding water in the engine right after I ran it up for inspection is enough for me. The inspection would find low compression or metal in the filter, and a cylinder would need to come off. Water in the rocker box, water between the piston and cylinder. Even without that, the milky chocolate stuff on a dipstick after a short flight in cold weather proves that moisture, lots of it, gets into a crankcase and mixes with the oil. The terrific amount of water/oil emulsion dripping out of a breather is another proof.

    People who have never seen it are skeptical. I get that. But I feel sorry for those that continue to ground-run their engines, thinking they're helping the engine last longer. I have run into too many of those in the shop, pitted cylinders and poor compression, rusty gears in the accessory case, and when I ask them if they've been ground-running it, it's always "yes." Those engines that sit undisturbed don't suffer anywhere near like that.

    Burning a gallon of gasoline produces a gallon and a half of water. Most goes out the exhaust, but in cold aircraft engines, some gets past the rings. It's not a doctoral-thesis thing. It's common knowledge for mechanics.
     
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  6. Snowmass

    Snowmass Pre-takeoff checklist

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    I need a peer reviewed, scientific studies to truly believe corrosion claims. Anecdotal claims are better than nothing but opinions are not the same as controlled experiments.
     
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  7. Checkout_my_Six

    Checkout_my_Six Touchdown! Greaser!

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    the salt spray test is hardly controlled or repeatable.....
     
  8. SoonerAviator

    SoonerAviator Final Approach PoA Supporter

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    It's repeatable. I can go out and spray all sorts of metal parts with salt water and watch them rust in a week, lol.
     
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  9. Dan Thomas

    Dan Thomas Final Approach

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    So, real experience means nothing. Even in the Ram video they say not to ground-run the engine. I guess they haven't really seen that damage in engine cores, either. Thousands of engine cores. Experience means nothing.
     
  10. Snowmass

    Snowmass Pre-takeoff checklist

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    I distinctly said "better than nothing", not "means nothing". Read my post again. Shall I try a different language?
     
    Last edited: Feb 28, 2020
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  11. Tom-D

    Tom-D Taxi to Parking PoA Supporter

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    There are so many variables in this subject it is impossible to predict what corrosion will occur in any material / or preservative.
     
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  12. GaryV

    GaryV Pre-takeoff checklist

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    I base out of KLBX, south of Houston. My hanger is less than 15 miles from the gulf coast and sits to the North of the coast. My experience does not match what RAM claims.

    Maybe using Phillips XC 20-50 and CamGuard is what makes the difference.

    Gary
     
  13. Rgbeard

    Rgbeard Cleared for Takeoff

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    Maybe because you don't take the added measure to spray your engine's innards with saltwater.