loud knocking at idle and while revving
#1
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loud knocking at idle and while revving
My friend's 95 started knocking under load and now knocks all the time. Head and valve train look ok. An inspection camera didn't find anything in the combustion chamber. Compression is 200/180/150/150. Is this a bottom end problem like a bent rod or spun rod bearing?
Engine is stock, no turbo, but it has 200k miles and unknown history from previous owners.
Engine is stock, no turbo, but it has 200k miles and unknown history from previous owners.
#6
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Ok, that's what we thought. New engine is already being sourced. My ls1 which had 1 spun bearing with only small amount of wear didn't sound nearly this bad, but would barely idle when it was pulled. This thing drove 50+ miles and still idles/revs all while clanking.
#10
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He was driving up to the corkscrew at Laguna when it happened so it's already seen some track time while knocking... While it might be fun to blow it up and possibly add a hole to side of the block I'd rather just swap it out now and open it up.
#12
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We pulled the motor today. Drained the oil... all 0.5 quart that was left. Spent most of the day swapping parts and redoing all the belts and seals on the new motor. If anyone has an extra carfax I'd appreciate if you can lookup the new motor in exchange for some $$$: JM1NA3536S0610298
#17
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Swapped the motor last weekend and it looks to be running good. Haven't had a chance to pull apart the old one, but we did cut open the filter. I think there's more than 4 bearings worth of metal in it:
53c14c94.jpg?t=1335407869
53c14c94.jpg?t=1335407869
#19
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What's left of the #4 rod bearing next to another half that looked fine. Nothing else was obviously broken from a quick inspection.
c4a60e15.jpg?t=1336022718
c4a60e15.jpg?t=1336022718
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