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  1. #1
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    Bad wrist pin question

    0g528934 serial number 200 efi the wrist pin in number 4 cylinder is worn everything else in motor looks good was knocking anyways replacing pistons all bearing etc. I'm having injectors cleaned anything else I should look at what could cause just one to go bad just fatigue or ? Thanks guys .

  2. Member
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    #2
    For sure replace the rod on 4. Be costly but since you're going that far,I would replace all 6. Make sure the crank is in good (great) condition. Check clearances on all pistons per service manual. Be a good time to replace the oil pump drive gear if you're still injected. Good luck and keep us posted.

  3. Member
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    #3
    So do you think this was a lubrication issue?

  4. Member
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    #4
    I mentioned the oil pump drive gear because it is a known failure point and easy to replace where you're at right now. I'm not saying it's a lubrication issue necessarily.I'm sure there is a reason for the wrist pin failure but sometimes it's hard or impossible to pinpoint.

  5. Member
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    #5
    Thanks for the reply I'll change the gear and having the injectors cleaned.

  6. Member
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    #6
    Anything else guys going back together soon just looking for reason wrist pin failed. And correct if there is one thanks

  7. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #7
    Might be a good idea to snap and post a few pictures. Really not a good idea to hazard guesses on this type of failure without something you can SEE (or even better- see, Feel and Measure).


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  8. Member Reel Life's Avatar
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    #8
    Never seen a wrist pin fail...I would think a lubrication issue would show up on the rod bearing or cylinder before the wrist pin. Might simply be a defective part. Did it wear loose in the piston, rod or both?
    Mark
    2003XB/225 Promax