Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Engine noise

Thread Tools
 
Search this Thread
 
Old May 22, 2016 | 07:19 PM
  #1  
Dragway's Avatar
Thread Starter
Teching In
 
Joined: Nov 2014
Posts: 29
Likes: 0
Unhappy Engine noise

To car to track for firs time made 1 pass have some kind of noise sounds like a light knocking noise like rod but still has good oil pressure . Anyone have any ideas on where to start checking ?
Reply
Old May 23, 2016 | 12:30 PM
  #2  
Taxman20's Avatar
TECH Resident
iTrader: (11)
 
Joined: Nov 2014
Posts: 976
Likes: 1
From: San Marcos, Tx
Default

Hard to give any ideas without hearing it running. Could be a bunch of things.
Rods, rod or main bearings, piston, wrist pin, lifter, rocker, bent pushrod, even a cracked flex plate or converter bolt or flywheel bolt came loose.
Reply
Old May 23, 2016 | 01:49 PM
  #3  
nine8ss's Avatar
Launching!
iTrader: (5)
 
Joined: Feb 2016
Posts: 253
Likes: 2
From: Tucson, AZ
Default

See if you can get the sound on video and post it here. You could also grab a mechanics stethoscope and narrow the sound location down. These two together should pinpoint your knocking noise.
Reply
Old May 23, 2016 | 01:55 PM
  #4  
Taxman20's Avatar
TECH Resident
iTrader: (11)
 
Joined: Nov 2014
Posts: 976
Likes: 1
From: San Marcos, Tx
Default

You can also just use a long screwdriver to locate the noise. Put the handle to your ear and start probing. Works just as good as a stethoscope and its free. I have a super long flathead screwdriver I use for this.
Reply
Old May 24, 2016 | 03:25 PM
  #5  
smws6ta's Avatar
Launching!
iTrader: (5)
 
Joined: Jan 2010
Posts: 237
Likes: 2
Default

1st thing to do, using the above mention methods, is around the oil pan and bottom of the block on both sides. If you detect it there chances are you have a rod issue.

2nd place would be along the heads, check several spots. If here you might have gotten lucky with a bent pushrod or valve.

Lastly, is to drain the oil in a clean pan and cut open the filter. You're looking for bearing material and metal flakes. All of these do not require you to crack into the motor.

This is if you need to dig further...

Pull the valve covers off, go through each rocker looking for any obvious loose or broken stuff. You will need to turn the crank over to go through each one. Try to check them when they are TDC.

If nothing stands out, this following method can help you see if you may have a collapse lifter. (Only do this if you've replace the oil or haven't drained it yet) It's messy but just short of pulling heads to see.....wipe all the rockers with a rag, you're trying to get any excess oil off, now using some cardboard, place it along the inside of the heads to keep the oil splashing to a minimal, hook up the coils and plug wires, the coils are going to rest on the cardboard, and start the motor. RUN AT IDLE...No rev ups unless you want an oil bath. Look at each rocker see if oil is pumping up. No oil chances are you found a bad lifter.
Reply
Old May 25, 2016 | 12:32 PM
  #6  
Dragway's Avatar
Thread Starter
Teching In
 
Joined: Nov 2014
Posts: 29
Likes: 0
Default

Was cancelling out cylinders today didn't change noise the use long screw driver started checking upper and lower end . Noise seems to become from flywheel tranny area as I was going under car noise just stopped can't get it to come back .
Reply




All times are GMT -5. The time now is 10:33 AM.