How did this engine stay together for 14 passes?

Discussion in 'Technical' started by rayzorsharp, Aug 26, 2006.

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  1. rayzorsharp

    rayzorsharp I "AM" a Maverick!

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    Hey Round-Up guys...I finally got time to dig into my engine to try to find out where the tapping noise was coming from. I had a couple of our engine techs listen to it with me before I starting taking it apart and they too thought it was in the top end. Well, I took the head off the noisy side and couldn't find anything obvious, even after completely disassembling the head. The cam checked out great, lifter bores were fine, had already replaced the lifters. I replaced a couple of the roller rockers at the motel before going to the track hoping I might get lucky as some of you know. Anyway, after running out of things to look at I finally decided to drop the pan and take a look at the pistons. There she was...a nice visible crack in the #6 piston skirt. I took the cap off and as soon as I started to push the piston upward, the bottom of the skirt fell into my hand. There appears to be a hairline crack on #2 also so she's coming all the way out now. I just can't believe that after making 14 passes on the track that it stayed together and I was turning her up well over 6K too. I guess I got lucky but then again I'm not sure yet if I did any block damage. I'll know more tomorrow when I get her on the stand. Anyway, here's a pic on my tapping noise:
     

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    rayzorsharp, Aug 26, 2006
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  2. CornedBeef4.6L

    CornedBeef4.6L no longer here

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    What brand piston?

    Good thing it didn't ruin your fun at the track:bananaman

    Is this the motor that got water logged?
     
    CornedBeef4.6L, Aug 26, 2006
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  3. rayzorsharp

    rayzorsharp I "AM" a Maverick!

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    TRW's...and yep, the same motor.
     
    rayzorsharp, Aug 26, 2006
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  4. T.L.

    T.L. Banned

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    Amazing.
    Yeah, what kind of pistons are those?...
     
    T.L., Aug 26, 2006
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  5. Mavaholic

    Mavaholic Growing older but not up!

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    Built Ford Tough!!!!

    Glad it held together long enough.
     
    Mavaholic, Aug 26, 2006
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  6. eddie1975

    eddie1975 Windsor Specialist

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    amen to that, build ford tough:yup:
     
    eddie1975, Aug 26, 2006
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  7. don graham

    don graham MCG State Rep

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    me thinks you got a little bit lucky ray.:yikes:
     
    don graham, Aug 26, 2006
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  8. Dan Starnes

    Dan Starnes Original owner

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    Wow!!! I woulda never guessed that. Amazing.
    Dan
     
    Dan Starnes, Aug 26, 2006
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  9. hotrod-daddy

    hotrod-daddy Member

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    I had a '74 Torino with a 302 do that exact same thing. I had to have the block bored and use oversize pistons.........and I thought I was lucky when my lug nut feel off after driving 3800 miles.......Glad you found what it was
     
    Last edited: Aug 26, 2006
    hotrod-daddy, Aug 26, 2006
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  10. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI

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    Man...that could have been scary stuff.
     
    Craig Selvey, Aug 26, 2006
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  11. maverick1970

    maverick1970 MCG State Rep

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    Sorry to hear that Ray, you got lucky!
    Who originally built the engine? Sounds like to much piston to cylinder wall clearance or rod bearing failure.
     
    maverick1970, Aug 26, 2006
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  12. ratio411

    ratio411 Member

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    SBF pistons are notorious for cracking at the skirts.
    Even Boss 302s had the problem when new... and those pistons were sourced from TRW if memory serves.
    Glad you caught it at a safe moment Ray.
    Dave
     
    ratio411, Aug 26, 2006
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  13. Dan Starnes

    Dan Starnes Original owner

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    Still freaks me out that the little tick we were hearing was that.
    Dan
     
    Dan Starnes, Aug 26, 2006
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  14. T.L.

    T.L. Banned

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    Forged?...
     
    T.L., Aug 26, 2006
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  15. rayzorsharp

    rayzorsharp I "AM" a Maverick!

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    yep...but quite old. They don't even make this particular one anymore. :huh:
     
    rayzorsharp, Aug 26, 2006
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