Hear my knock
Hear my knock Yup another Ls1 knocking, I just bought the car and trying to diagnose this. I've been through quite a few of these knocking engine videos now and most seem to be piston slap or a bad bearing. The knocking stays pretty consistant warm and cold, so I have a feeling its bottom end. Oh engine has 94k; let me know what you think.
http://www.youtube.com/watch?v=LF_upMqfv7M
http://www.youtube.com/watch?v=LF_upMqfv7M
Sounds like a stereotypical rod knocking or exhaust leak.
Im betting on the rod knocking. (checkover valvetrain first though since its easiest to lookover)
Main bearing failure is usually more of a growl (low pitch) like a roller bearing failed without the high pitch noises.
Im betting on the rod knocking. (checkover valvetrain first though since its easiest to lookover)
Main bearing failure is usually more of a growl (low pitch) like a roller bearing failed without the high pitch noises.
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Pull the oil filter and cut it open, if its a rod bearing you will see something in the oil filter. Make another video with you revving it from a idle up quickly to like 2k. If its a rod bearing it will knock louder as you start to rev it. Its very possible it just a lifter but you need to check the oil and filter for metal-copper etc 1st to have some idea.
Last edited by O2Form; Mar 27, 2011 at 09:26 PM.
It sounds like really loud piston slapping to me, at least from that vid.
See if you can put your camcorder under the car near the oil pan and give it a few short revs. Rod knocks will usually be a very heavy sounding clunking much different than valvetrain noise or piston slap.
How is your oil pressure? When rod bearings start to go, oil pressure will drop off some depending on how bad it is.
See if you can put your camcorder under the car near the oil pan and give it a few short revs. Rod knocks will usually be a very heavy sounding clunking much different than valvetrain noise or piston slap.
How is your oil pressure? When rod bearings start to go, oil pressure will drop off some depending on how bad it is.
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Verdad Gallardo Ok got the oil filter opened up and I don't see anything obvious in it. Should I open up the filter itself and check the inside of it too? I also drained the oil from the oil filter into a coffee filter; its taking long time but I'll try to get some pictures up after its drained and of the oil filter too.
Last edited by Triaxle; Mar 28, 2011 at 12:29 PM.
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well if t was a bearing you wooooood see something in the oil-glittery looking. Cut the filter open and you will see what looks like paper in the shape of a W pull that apart carefully and have a close look. Pulling the valve covers is a great idea too, look for bent broken parts. Maybe a stuck lifter<rocker will have play. You will have to rotate the engine to check them all.
Well I think its time to get into the engine more, I took some pictures of the filter and of what i put through the coffee filter but they didn't come out very good at all. I saw a few small pieces of metal in what I filtered but im 90% sure its from me tearing the filter case open. I had to tear it open to get the 2nd half of the oil to drain out. So I'll post what I find if anything at all after getting inside the engine.
Honestly I agree with the above almost sounds like really bad piston slap... Does it go away if you rev the motor over 2k? If you cant find ANY evidence in the oil its highly doubtful it puked a bearing. Also your oil pressure for the brief time I saw it looks high and steady usually when a rod bearing goes the oil pressure will be either very erratic or non-existent.
Honestly I agree with the above almost sounds like really bad piston slap... Does it go away if you rev the motor over 2k? If you cant find ANY evidence in the oil its highly doubtful it puked a bearing. Also your oil pressure for the brief time I saw it looks high and steady usually when a rod bearing goes the oil pressure will be either very erratic or non-existent.
sounds more valvetrain related by how slow it taps.I would pull both valve covers and check everything in there first.Its pretty easy to do that before you go looking somewhere else
Alright I made another video with the camera under the car, its not much different from the hood angle. Also had a mechanic listen to it and he seems to think its bottom end but I'm not sold on that just yet. One other thing I noticed is when I started it up this morning at about 35 degrees or so the knock seemed to be a little louder and a little more high pitched until the engine got warmed up. So heres the new vid.
http://www.youtube.com/watch?v=J3YmReV2Y5k
http://www.youtube.com/watch?v=J3YmReV2Y5k
Alright I made another video with the camera under the car, its not much different from the hood angle. Also had a mechanic listen to it and he seems to think its bottom end but I'm not sold on that just yet. One other thing I noticed is when I started it up this morning at about 35 degrees or so the knock seemed to be a little louder and a little more high pitched until the engine got warmed up. So heres the new vid.
http://www.youtube.com/watch?v=J3YmReV2Y5k
http://www.youtube.com/watch?v=J3YmReV2Y5k
^^^^ My car is the same way first 30 sec or so cant hear anything. After that you can the slap. That doesnt sound like slap. A rod has a very noticable noise when its going out. Your car sounds like a rod knocking imo, What weight oil are you running?
Running 5w-30. Well you may be right about the rod, I have a 6.0 shortblock I'm gonna be switching over in a few weeks. I might just park it until then. At this point theres really no good way to tell how far gone a bearing is without tearing down is there?
Rod or lifter for sure. We have a dodge dakota that ate a lifter and sounds a lot like that. But at moments yours sounds like a good deep bent rod type thud. motor needs to come apart either way though for sure.