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True or false? Cylinder distortion question...

Discussion in 'The Hokey Ass Message Board' started by Carguy365-24-7, Oct 2, 2009.

  1. Carguy365-24-7
    Joined: Mar 25, 2006
    Posts: 909

    Carguy365-24-7
    Member

    I was talking to a guy at a carshow the other day and I told him that I had a 261 chevy 6 on a stand at home .He told me that if it hangs for a long time it can distort the cylinders.Has anybody ever had a problem with that?
    I've had it on my stand for about 3 yrs with the head unbolted and resting on top and the crank is still in it.My 216 still runs good so I'm in no hurry to replace it so it may sit a few more years...PAUL
     
  2. At an auction the other day I noted piston and sleeve assemblies for big diesel truck motors marked on their boxes to stand on end or they could distort in sitting. But that was just the sleeve, it seems unlikely the block itself would change shape much.
     
  3. squirrel
    Joined: Sep 23, 2004
    Posts: 55,936

    squirrel
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    Everything I learned in mechanical engineering school about how materials behave tells me that it would not have any affect.

    But hey, what do engineers know? Maybe the yield stress of cast iron is way way lower than they told us :)
     
  4. Truckedup
    Joined: Jul 25, 2006
    Posts: 4,661

    Truckedup
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    Yeah,the cast iron gives in to gravity.A few more years and the engine on the stand will be a puddle on the floor.
     

  5. 6inarow
    Joined: Jan 24, 2007
    Posts: 2,361

    6inarow
    Member

    The biggest "distortion" you get from those series engines is when they are being rebuilt. When they are bored, its best to use a head plate (that mimics the torque from the head bolts) and have the bell housing bolted to them. But just sitting there isnt going to cause a problem.

    But if you are really worried, I'll give you $25 scrap for your 261 and take my chances....
     
  6. pasadenahotrod
    Joined: Feb 13, 2007
    Posts: 11,775

    pasadenahotrod
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    from Texas

    If this were true, no hotrodders engines would be any good. Many spend years on stands waiting for chassis, another car, etc.
     
  7. squirrel
    Joined: Sep 23, 2004
    Posts: 55,936

    squirrel
    Member

    The stress on the bores from hanging on a stand is way way less than from the head bolts and combustion pressures....

    Better not leave crankshafts laying on their side, or batteries sitting on the concrete floor, etc either
     
  8. RugBlaster
    Joined: Nov 12, 2006
    Posts: 563

    RugBlaster
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    There is such a thing as a torque plate. If there is any distortion it is not preceptable and corrects itself, I think it's called elastic deflection.
     
    Last edited: Oct 2, 2009
  9. Dyce
    Joined: Sep 12, 2006
    Posts: 1,973

    Dyce
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    Never a lack of kindness on the HAMB. But did you just admit an inline is worth scrap price?:eek: Ha I'm framing this post:D
     
  10. pitman
    Joined: May 14, 2006
    Posts: 5,148

    pitman

    Yep, and glass is a super-cooled liquid. So all window panes are slowly heading south.
    It might be worth doing a search on the subject of "creep". The interplanar slippage due to low but continuous loads on certain metals. Most cast iron material has lot of carbon present that would lock things in place if I recall correctly.
     
    Last edited: Oct 3, 2009
  11. oneratfink57
    Joined: Feb 12, 2006
    Posts: 737

    oneratfink57
    Member
    from Wisconsin

    my motor spent over 6 months on a stand built and oh boy does she pull ;)

    and if you can wait, next term im taking materials class at my engineering school so ill let you know
     
    Last edited: Oct 2, 2009
  12. I had blocks on stands for years never had any problems with distortion.
     
  13. 6inarow
    Joined: Jan 24, 2007
    Posts: 2,361

    6inarow
    Member

    Ah, uh, well. ummmmm.

    Crap, what did I just say??? Where is the delete button? nobody around here will believe I said that anyhow.
     
    Last edited: Oct 2, 2009
  14. Hi!
    Joined: Oct 4, 2006
    Posts: 731

    Hi!
    Member
    from SoCal

    Good thing thats solved. I was woried about my machine equipment sitting.
     
  15. Koolade
    Joined: Feb 11, 2008
    Posts: 123

    Koolade
    Member
    from Illinois

    I'd heard a long time ago that because of this same thing Billy Glidden built his engines on the floor, but who knows, that might be as much because he'd done it that way and won, so he didn't want to chance it, or maybe it's not true at all. Interesting rumor I thought.
     
  16. I have a 396 on the stand in my garage now, for about 5 years. I did block up the front of it, just to take the stress off the bolts holding the engine to the stand.

    I doubt anything could happen to a block dimensionally from being held that was for a long long time.

    Bob
     
  17. RAY With
    Joined: Mar 15, 2009
    Posts: 3,132

    RAY With
    Member

    Bore and honeing the block with plates keeps the cylinders from distorting due to heat and it also pulls the cylinder the same way it would if it had a head bolted to it. Installing the same machined motor on a engine stand has no effect as to distorsion and if it did hundreds of thousands of motors would be scraped each year. It makes for a good wifes tail though
     
  18. retromotors
    Joined: Dec 10, 2008
    Posts: 1,045

    retromotors
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    Tale .... Tale....!!
    Damn, it's always sex with some of you guys!:D:D:D
     
  19. R Pope
    Joined: Jan 23, 2006
    Posts: 3,309

    R Pope
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    Any distortion would be a sagging of the whole block, that would make the head gasket leak long before it affected the bores. Like the window glass story, maybe in ten thousand years or so! Or not......
     
  20. carcrazyjohn
    Joined: Apr 16, 2008
    Posts: 4,843

    carcrazyjohn
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    from trevose pa

    I think that the stand would bend before the engine .
     
  21. Retro Jim
    Joined: May 27, 2007
    Posts: 3,854

    Retro Jim
    Member

    Haven't heard of this one before ! I guess I have some bad block now !

    I have heard that when you tear down your engine that if you lay your crank flat on the bench or floor for a long period that the crank distort and not be true . I always hang mine from the crank bolt or store in a crank crate . Is this true about the cranks going bad ?

    RetroJim
     
  22. Zookeeper
    Joined: Aug 30, 2006
    Posts: 1,042

    Zookeeper
    Member

    I read the same thing once when SS&DI magazine toured his Dad Bob Glidden's shop. I think his 10 championships and 85 wins mean he is likely smarter than pretty much anyone I know, so who is qualified to argue the point? Having said that, I've always built motors on an engine stand and never had a problem.
     
  23. noboD
    Joined: Jan 29, 2004
    Posts: 8,458

    noboD
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    Don't know about the "super cooled" liquid part, but put a micrometer on a 150 year old window pane that's been in the same window since new. It will always measure smaller at the top and the bubbles are oval shaped drooping DOWN. But I doubt that an engine hanging on an engine stand will go anywhere that matters.
     
  24. pitman
    Joined: May 14, 2006
    Posts: 5,148

    pitman

  25. Shifty Shifterton
    Joined: Oct 1, 2006
    Posts: 4,964

    Shifty Shifterton
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    Without trying to further sidetrack this, one might think if it's much concern then the even bigger risk would be to the cam bores. After all, any creep in the block would have 6 cylinders to distribute across, but the cam's centerline would take it all.

    Put a 2x4 under the front of the block if it's a real concern. I might anyway, just for the sake of the stand, that's a lot of leverage and I woudn't want the stand to take a set :)
     
  26. My engine stand can take it! As for the window glass theory, I've heard that one too. Guess we need to call Mythbusters, at least we'd get to see Kari Byron.
     
  27. Carguy365-24-7
    Joined: Mar 25, 2006
    Posts: 909

    Carguy365-24-7
    Member

    Thanks guys! I kinda figured as such .I completed a 2 yr. Automotive tech program back in the 80's which included a class on machine shop and I never recall anything like this....Paul
     
  28. Hi!
    Joined: Oct 4, 2006
    Posts: 731

    Hi!
    Member
    from SoCal

    Oh Boy. The old glass settling is true if it was made turn of the century. Later glass has more lead or silicon. I dont remember what was told to me.:D So if you have a early glass motor, pull it off the stand as fast and carefull as possible.
    As far as Glidden building motors on the ground. It was problably easier to hide the nitrous ports in the heads that way.:D
     
  29. I always stand mine up between the studs on the sill of my garage. I had heard about it years ago and seen them stood up in old factory pictures. Cams I either leave new in the box on the shelf and lay them down flat.

    I guess you can take anything to an extreme if you were AR enough to measure up a laying crank vs a stood up one.

    Bob
     

  30. There was a huge discussion about this on another forum recently. It was entertaining, to be sure.

    My opinion-FWIW- is that it makes no difference whatsoever. My trusted crank guy says it makes no difference. Most respected engine builders agree as well.

    On a more substantial note, I have a never used 427 steel crank, all fresh & pretty-like from GM, that I bought new years ago- like at least 25 years. It's been stored in the box, lying flat, ever since (though it has been moved a few times, and opened/inspected/recoated with preservative occasionally). For the purposes of that discussion I dragged it out & verified that it was still straight. (It was checked & tagged straight originally as well.) FWIW....

    I think it saves space to hang them by the bolt or crank flange, though. :)

    And this 427 crank is finally gonna get used...:D
     
    Last edited: Oct 3, 2009

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