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  1. #1
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    "Burnt" spark plugs

    Went out for a small run yesterday and once i got back i noticed that 2 plugs were burnt. pics below of one burnt and one not burnt. Also, one of the cylinders has no compression now. I think im taking the head of that side to check if the valves are closing correctly.

    Any suggestions as to what may have caused this?
    Attached Images Attached Images

  2. #2
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    The porcelain has a green tint. Green=lean. Tuliped an exhuast valve or a lifted ring land is my guess. Now, why did it go lean in that hole????

  3. #3
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    it's not good....what is the engine setup ??

  4. #4
    Charter Member Charter Member Ted G's Avatar
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    Looks like detonation damage, if you really have 0 compression you likely holed a piston.
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  5. #5
    Platinum Member Platinum Member Throttle Fever's Avatar
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    Quote Originally Posted by Ted G View Post
    Looks like detonation damage, if you really have 0 compression you likely holed a piston.
    I am with Ted, Lets hope we are wrong.

  6. #6
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    Fixx

    All the above! or blown head gasket between cylinders,if so hopefully it didn't hurt the deck of the block..502???

  7. #7
    Platinum Member Platinum Member 1BIGJIM's Avatar
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    What cylinders? What year?

    Whey you burn a hole in piston you will see metal all over the plug and the plug will look worse than that.
    I would also go with blown head gasket.

    I had a problem last year with zero compression in one cylinder, it was an exhaust seat. Valve was not closing all the way.

  8. #8
    VIP Member VIP Member lightning jet's Avatar
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    my guess is a head gasket,was there any water in the hole?

  9. #9
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    don't think a head gasket would burn the end of a plug off like that...

  10. #10
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    no water in the hole. the pistons are new 4.530, block is a 502 bored to .06

    i think that i have a combination of problems, thin head gasket (.03) hot spark plugs and low octane gas.

    the oil was clean as well


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