KNOCK.. not good.. need major advice PLEASE!!
03-27-2009, 05:59 PM
#41
2-3 quarts being burnt off in 6,000 miles is not unreasonable, and if you beat on that car you shouldnt run synthetic to 6,000 anyway, you could have lost a bearing to oil breakdown also.
Anyway to me it sounds like a rod bearing but you should have found copper shavings in the oil and **** on the plug, have you pulled the other valve cover yet? ran the engine with the belt off to eliminate accessories? torque converter/flywheel bolts can also cause a knock if loose.
And I have also seen a LS1 with spun bearings have good oil pressure. Best of luck to you. And from now on change that oil sooner, if you beat on it more than average you need to maintain it more than average.
Anyway to me it sounds like a rod bearing but you should have found copper shavings in the oil and **** on the plug, have you pulled the other valve cover yet? ran the engine with the belt off to eliminate accessories? torque converter/flywheel bolts can also cause a knock if loose.
And I have also seen a LS1 with spun bearings have good oil pressure. Best of luck to you. And from now on change that oil sooner, if you beat on it more than average you need to maintain it more than average.
03-27-2009, 11:35 PM
#43
let's put it this way... my old LS1 had rod knock, spun bearings, lifter failure, every valve hit every piston...
and it still managed to make 300+ rwhp after 10 runs on the dyno with all those problems!
had great oil pressure the whole time...
but the sound you have is definitely rod knock... I'd bet money on it...
03-29-2009, 12:18 AM
#45
my question is where did that oil go in the first place?? I didnt change my oil for 6000 miles once and my oil was always full. Sounds like you have more issues too. I would just say bye bye to that motor and do the ls2 like you have posted in your other thread.
03-29-2009, 12:24 PM
#46
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alright well i pulled the head on the side with the noise and the lifters seemed fine.. minor scarring on 2 of them but nothing serious..
so now with lifters and pushrods ruled out im not looking forward to finding this rod knock...
one piston had the top third of it clean while the rest wasnt.. this i have no idea what it could be
all the valves looked to be in clean condition... ill post pics soon
pulling the oil pan next
so now with lifters and pushrods ruled out im not looking forward to finding this rod knock...
one piston had the top third of it clean while the rest wasnt.. this i have no idea what it could be
all the valves looked to be in clean condition... ill post pics soon
pulling the oil pan next
03-29-2009, 02:01 PM
#47
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based on what you just said and listening to your video, I'd say the rod under that clean piston is the culprit. The timing of the noise in the video is consistant with a rod getting ready to let go. At this point, if it were my ride, I'd plan on it not being an "in car" repair. Even if you could just repair it in the car, one bad bearing is indication that the others aren't far behind. I'm with Z28Steve; I'd prep another engine for swap.
03-29-2009, 02:03 PM
#48
MHO...
pull the other valve cover if you haven't already. something I've learned with these motors is they can make engine problem noise do funny things. I had a rocker arm break on mine and the sound from the pushrod bouncing off the underside of the valve cover sounded deeply internal. even the smallest amounts of metal, cleaned up and examined, can tell you worlds about what the condition of your motor is. local oil test facilities are a wonderous thing, if you have them in your area.
any clean, shiny metal surfaces that are not consistant with the rest of the motor should be looked at, along with the surrounding pieces of the shiny location to try and determine why that area reacted differently than the rest and if it is a concern.
if a rod or crank bearing is toast, and the others do not show extensive wear or damage, it would be acceptable to replace that bearing, recheck your tolerances on that journal, and go. if the crank/rod journals had any defects large enough to catch a fingernail on, id see if the crank can be polished, and if the defect is too large, turned down and reinstalled with oversized bearings.
when everything is done, if in doubt, by all means rebalance the rotating assembly. 1 ounce of unbalanced metal on a counterweight has a dynamic weight of 700-something pounds at 6k rpm.
don't know your knowledge level, but remember to index your caps and bolts if you start pulling the crank to check the journal/bearing condition.
good luck!
pull the other valve cover if you haven't already. something I've learned with these motors is they can make engine problem noise do funny things. I had a rocker arm break on mine and the sound from the pushrod bouncing off the underside of the valve cover sounded deeply internal. even the smallest amounts of metal, cleaned up and examined, can tell you worlds about what the condition of your motor is. local oil test facilities are a wonderous thing, if you have them in your area.
any clean, shiny metal surfaces that are not consistant with the rest of the motor should be looked at, along with the surrounding pieces of the shiny location to try and determine why that area reacted differently than the rest and if it is a concern.
if a rod or crank bearing is toast, and the others do not show extensive wear or damage, it would be acceptable to replace that bearing, recheck your tolerances on that journal, and go. if the crank/rod journals had any defects large enough to catch a fingernail on, id see if the crank can be polished, and if the defect is too large, turned down and reinstalled with oversized bearings.
when everything is done, if in doubt, by all means rebalance the rotating assembly. 1 ounce of unbalanced metal on a counterweight has a dynamic weight of 700-something pounds at 6k rpm.
don't know your knowledge level, but remember to index your caps and bolts if you start pulling the crank to check the journal/bearing condition.
good luck!
Last edited by nine-eight; 03-29-2009 at 02:24 PM.
03-30-2009, 11:00 AM
#51
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Based on what you're saying and the pictures... I think this guy said it all. I'm going with rod knock as well. Hope it's not, but evidence is starting to show otherwise. Best of luck either way man. Damn cars!
03-30-2009, 12:04 PM
#52
fraid so. your piston has been kissing the underside of your combustion chamber.
yank the motor
index the rod caps, throw away the bolts
yank the crank, take it with the heads down to the machine shop and have them inspect and check for straightness. if he has to mill the kissed one to true it up he might as well have both.
new bearings, new rods if one of the stockers is messed up, rebalance rotating assembly with new bolts and reinstall everything. chleck valves on kissed cylinder head.
or,
buy 402 shortblock and a 1300 dollar set of patriot heads and be done with it.
wheeeeeeee!
yank the motor
index the rod caps, throw away the bolts
yank the crank, take it with the heads down to the machine shop and have them inspect and check for straightness. if he has to mill the kissed one to true it up he might as well have both.
new bearings, new rods if one of the stockers is messed up, rebalance rotating assembly with new bolts and reinstall everything. chleck valves on kissed cylinder head.
or,
buy 402 shortblock and a 1300 dollar set of patriot heads and be done with it.
wheeeeeeee!
03-30-2009, 12:12 PM
#53
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fraid so. your piston has been kissing the underside of your combustion chamber.
yank the motor
index the rod caps, throw away the bolts
yank the crank, take it with the heads down to the machine shop and have them inspect and check for straightness. if he has to mill the kissed one to true it up he might as well have both.
new bearings, new rods if one of the stockers is messed up, rebalance rotating assembly with new bolts and reinstall everything. chleck valves on kissed cylinder head.
or,
buy 402 shortblock and a 1300 dollar set of patriot heads and be done with it.
wheeeeeeee!
yank the motor
index the rod caps, throw away the bolts
yank the crank, take it with the heads down to the machine shop and have them inspect and check for straightness. if he has to mill the kissed one to true it up he might as well have both.
new bearings, new rods if one of the stockers is messed up, rebalance rotating assembly with new bolts and reinstall everything. chleck valves on kissed cylinder head.
or,
buy 402 shortblock and a 1300 dollar set of patriot heads and be done with it.
wheeeeeeee!
as much as id love to just throw the money out there for the 402 and patriot heads i dont have it =[
i do however have a guy with a ls1 shortblock with 3000 miles on it for 800... any idea what the milling and **** would cost if i were to try and fix my block?
03-30-2009, 08:10 PM
#57
Again, look at that one piston that does not have any carbon buildup in the quench area, the part of the cylinder head that is flat, i.e. no combustion chamber. It's clean because your quench area is zero because the piston is hitting the cylinder head
