Best way to confirm Spun Bearing
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Best way to confirm Spun Bearing
My buddies GTO recently was put on the dyno after a head, cam, and supercharger install. Long story short it made 7 dyno pulls and maxed out the fuel system. Upon getting in the car 2 days later to take i home and change the fuel pump it developed on sick (what sounds like a) rod knock. We drained the oil found specs of gold/bronze material (made me think bearing) and also some shiny tinge to the oil when you played with it. Thing is weve only run it for about 1 minute total since this started so theres no tale tell signs. the car is a GTO so.....no oil psi guage. Im just gonna shoot myself if I advise him to get a new bottom end for 3k+ after hes broke from putting together the last 10k$ build and its something stupid that I missed. Thanks for any advice
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Whatever you do, be more then sure before you mess with it. I've pulled a motor out o an fbody that over 5 experienced mechanics said was a rod knocking. 1 mechanic said it sounded like an accessory. Pulled the motor and tore it down to the Short book then noticed that the balancer had a break in it!!!
#4
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A rod knock will typically get louder with a pload placed on the engine. If its an auto, hold your foot on the brake and lightly apply the throttle. If it's a stick, pull the ebrake and release the clutch slightly to slow down the engine and load it.
Metal in the oil usually means it's got to come apart though.
Cut the oil filter open and see what it looks like on the outside of the element.
Pull the pan and pull a rod cap off... even if it's not the spun one, youll see scoring from the debris on the bearing.
Metal in the oil usually means it's got to come apart though.
Cut the oil filter open and see what it looks like on the outside of the element.
Pull the pan and pull a rod cap off... even if it's not the spun one, youll see scoring from the debris on the bearing.
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yeah I think Im just in denial at this point. the oil had only seven dyno pulls on it and came out black, thin, and smelled like someone took a grinder to a steel bar
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we just found a lot of metal on the end of the dipstick as we were preparing the removal. I think it just set in for me. Thanks guys for all of the replys. I think Im actually a little more upset than my buddy thats having the issue. Like we always say, gotta pay to play. Looks like forged 370 and 14 psi is one the way sooner than we planned. Everyone have a good evening
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#11
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I was going to say put a piece of wood against the oil pan and listen to it when its running and checking the oil, hearing a audible sound and seeing glint in the oil are tell tail signs.
Otherwise a physical/visual inspection of the bearing is the only other way.
Otherwise a physical/visual inspection of the bearing is the only other way.