devloped a knock.. check out the video please
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Racer
Joined: Nov 2016
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From: san antonio texas
devloped a knock.. check out the video please
more bad news guys....just when i thought i was getting ahead..its a 2005 ls2 with 64k on it..
it started as a really light clicking that i thought was a lifter..(still could be)..know it has gotten louder...i can hear from inside the cab ... a light throttle acceleration...it gets louder and then quiets down at about 2800rpm..
so my son helped me pull the valve covers to look for anything obvious, i have not yet measured the pushrods or checked if there bent..but i decided to check the oil filter...it looks bad
heres a video...tell mre what you guys think.. the knock definately down low... could be a roller or a rod bearing.... or both...
it started as a really light clicking that i thought was a lifter..(still could be)..know it has gotten louder...i can hear from inside the cab ... a light throttle acceleration...it gets louder and then quiets down at about 2800rpm..
so my son helped me pull the valve covers to look for anything obvious, i have not yet measured the pushrods or checked if there bent..but i decided to check the oil filter...it looks bad
heres a video...tell mre what you guys think.. the knock definately down low... could be a roller or a rod bearing.... or both...
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Does the "knock" increase with engine rpm?
Not in sound, but in occurrences the knock (rattle noise) it is heard?
Lifter or camshaft concern usually doesn't go away as rpm's increase, rod knock would increase in sound with engine rpm as well, and usually doesn't get quieter.
Had a similar noise concern on my brother's C4, sounded light at first, thought it was roller lifter or valve train issue, ended up being the main thrust bearing, went away or decreased in sound at higher rpm too.
Not in sound, but in occurrences the knock (rattle noise) it is heard?
Lifter or camshaft concern usually doesn't go away as rpm's increase, rod knock would increase in sound with engine rpm as well, and usually doesn't get quieter.
Had a similar noise concern on my brother's C4, sounded light at first, thought it was roller lifter or valve train issue, ended up being the main thrust bearing, went away or decreased in sound at higher rpm too.
Thread Starter
Racer
Joined: Nov 2016
Posts: 266
Likes: 24
From: san antonio texas
Does the "knock" increase with engine rpm?
Not in sound, but in occurrences the knock (rattle noise) it is heard?
Lifter or camshaft concern usually doesn't go away as rpm's increase, rod knock would increase in sound with engine rpm as well, and usually doesn't get quieter.
Had a similar noise concern on my brother's C4, sounded light at first, thought it was roller lifter or valve train issue, ended up being the main thrust bearing, went away or decreased in sound at higher rpm too.
Not in sound, but in occurrences the knock (rattle noise) it is heard?
Lifter or camshaft concern usually doesn't go away as rpm's increase, rod knock would increase in sound with engine rpm as well, and usually doesn't get quieter.
Had a similar noise concern on my brother's C4, sounded light at first, thought it was roller lifter or valve train issue, ended up being the main thrust bearing, went away or decreased in sound at higher rpm too.
Last edited by 1hander; Jan 28, 2017 at 08:21 PM.
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OK, you already have the valve covers off if I understand correctly..........if there was an issue with a lifter or pushrod, you would have play or slop in the rocker arms............
in my opinion, with the debris in the oil, and on the magnet shown in the video, more than likely a bearing issue, with material damage to either a rod or crank journal................
just a FYI - when you used the coffee filter to show the particles, that is a better method, as the paper composition is finer, and will trap more debris than cloths, or other types of paper..........that made it easier to see the amount of debris in the oil..........
if you check the valvetrain without any issue seen, next step would be to pull the oil pan in my opinion...........
in my opinion, with the debris in the oil, and on the magnet shown in the video, more than likely a bearing issue, with material damage to either a rod or crank journal................
just a FYI - when you used the coffee filter to show the particles, that is a better method, as the paper composition is finer, and will trap more debris than cloths, or other types of paper..........that made it easier to see the amount of debris in the oil..........
if you check the valvetrain without any issue seen, next step would be to pull the oil pan in my opinion...........
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Racer
Joined: Nov 2016
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From: san antonio texas
i checked all the push rods and all are the same length to within .0002 so in effect they are all the same... the rockers have no crunchiness to the bearings... everything on top appears to be right..
how hard is it to get the oil pan out... im pretty sure im going to find a chewed up rod bearing...
the only other thing i can do on top is pull the heads to check and see if i have a bad roller ...otherthan that its going to be a bottom end issue.. (bearing) in which case it probably wont be as simple as replacing a bad bearing..because i still wont know what caused it... i suspect this engine has had a hard life by the previous owner...or maybe someone put the wrong oil viscosity in it which will kill these engines..
in which case im not going to fawk with it.. ill just have to get started on that stroker a little sooner than planned..dammetttttt
how hard is it to get the oil pan out... im pretty sure im going to find a chewed up rod bearing...
the only other thing i can do on top is pull the heads to check and see if i have a bad roller ...otherthan that its going to be a bottom end issue.. (bearing) in which case it probably wont be as simple as replacing a bad bearing..because i still wont know what caused it... i suspect this engine has had a hard life by the previous owner...or maybe someone put the wrong oil viscosity in it which will kill these engines..
in which case im not going to fawk with it.. ill just have to get started on that stroker a little sooner than planned..dammetttttt
Last edited by 1hander; Jan 28, 2017 at 09:25 PM.
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there may be an older post here on the forum, probably in the "General" area that may give directions on the pan removal...........not sure of that..........if not, there may be a video one on YouTube....................good luck with it, and keep updates on the progress coming along here
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You are really going to be pulling the entire thing anyhow. I would just tear it down to block and then pull it in order to place it on an engine stand. I don't think there is any hope at this point.
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Racer
Joined: Nov 2016
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From: san antonio texas
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Sound wont disappear it will get higher if its a bearing issue and youll hear it too when you let off the gas. Did you notice any drop on your oil pressure before this knock developed?
---Edit
Is there a chance that you can record the knocking noise? or anything similiar to this?
---Edit
Is there a chance that you can record the knocking noise? or anything similiar to this?
Last edited by ogulcanio; Jan 29, 2017 at 06:44 AM.
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From: Auburn Ca
What if it is a cam lobe?
What if its a bad lifter?
OP pull heads off and inspect valve train and lobes, these are common failures as opposed to rod bearing issues.
Ticking is normal on these engines as is some light tapping, mine tapped loud after 1500 all the way to 3k and when I pulled the cam and lifters they were all perfect.
Now it has light tapping on and off under 2k which is all normal.
Thread Starter
Racer
Joined: Nov 2016
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From: san antonio texas
i think you guys are on to something.. just for grins i decided to change the oil...what was in there was not 5w30 it was too thick..
so with the old oil it idled at 37-40 psi hot... and the noise i was hearing was wa almost immediately audible..(but not when i first got the car)
i changed the oil to 5w30... and when i started it ...it was super quiet...only some light valve train noise... once it fully warmed up... the knock started again. but get this ...now it only does it at idle as soon as i lightly tap the throttle to anything above idle(when oil pressure hits 24) the noise is gone...
also might be tne cause of the problem, is that at idle now with 5w30 it idles at 21-23psi hot...i think that is to low.
so my theory which is probly complete ****... that the oil pump has become weak...low oil pressure could have caused a lifter not pumping up properly problem(knock at low rpm) ..which resulted in a slightly chewed up cam..(this could be part of the knock as well..
im open to all theories..but i think its an oil pressure problem and the shitty dealer put thicker oil in to mask the noise..once the oil had enough miles on it/...it started making noise again
so with the old oil it idled at 37-40 psi hot... and the noise i was hearing was wa almost immediately audible..(but not when i first got the car)
i changed the oil to 5w30... and when i started it ...it was super quiet...only some light valve train noise... once it fully warmed up... the knock started again. but get this ...now it only does it at idle as soon as i lightly tap the throttle to anything above idle(when oil pressure hits 24) the noise is gone...
also might be tne cause of the problem, is that at idle now with 5w30 it idles at 21-23psi hot...i think that is to low.
so my theory which is probly complete ****... that the oil pump has become weak...low oil pressure could have caused a lifter not pumping up properly problem(knock at low rpm) ..which resulted in a slightly chewed up cam..(this could be part of the knock as well..
im open to all theories..but i think its an oil pressure problem and the shitty dealer put thicker oil in to mask the noise..once the oil had enough miles on it/...it started making noise again
Last edited by 1hander; Jan 29, 2017 at 03:53 PM.
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From: Auburn Ca
Crank/rod Bearings are typically the cause of lower oil pressure.
Yours is not that low and lifter noise is also typical.
Oil pump is not an area I would focus on.
Mine does that now and its fresh and runs like a champ
Yours is not that low and lifter noise is also typical.
Oil pump is not an area I would focus on.
now it only does it at idle as soon as i lightly tap the throttle to anything above idle(when oil pressure hits 24) the noise is gone...
Mine does that now and its fresh and runs like a champ
Thread Starter
Racer
Joined: Nov 2016
Posts: 266
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From: san antonio texas
I can't complain Cuz it runs great.. It's just that Dam knock is so unsettling you know.. Like I said.. I suspect it's had a hard life..
Leak down across the board is less than 7 percent on a hot motor.. That rules out rings
Not much left but the bottom end bearings like you stated
Leak down across the board is less than 7 percent on a hot motor.. That rules out rings
Not much left but the bottom end bearings like you stated