Clicking Noise from Front of LS1
10-02-2014, 03:48 PM
#1
Instructor
Thread Starter
Member Since: Jan 2011
Location: Buffalo Grove Illinois
Posts: 176
Likes: 0
Received 1 Like
on
1 Post
Clicking Noise from Front of LS1
I have just recently began having a clicking noise on my car when it is first started which continues until it comes to normal operating temperature. The noise seems to be from the front, NOT inside the valve covers. I have put a stethascope on both valve covers, exhaust manifolds, intake manifold and I only hear the normal valvetrain noises of the LS1 when I do that.
The car is not low on oil. I changed the oil to see if that helped and it did not. I changed the plugs yesterday and all the plugs were dry and looked good. Oil pressure seems normal when warm 25 PSI at idel 65 PSI at higher RPM.
It almost seems it is coming from the front of the engine but putting the stethascope on the front cover the noise is not from within there.
The noise dissapears completely after the engine is at temperature. It does not have the same rythm as the valvetrain.
I was thinking of taking off the serpentine to see if it is generated from an accessory. It is not the water pump or power steering pump as I have listened to both those with the stethascope and the noise isnt there. I Recently did a Mantic Twin-disc clutch upgrade. There were no added weights on the flywheel. I did not match balance the new FW/PP to the previous one but the clutch and drivetrain are vibration free. In fact less vibration than before the clutch upgrade. Car runs fine otherwise. I was leaning towards accessories or a bad plug wire (insulation). I am putting a new set of GM red wires on today.
Motor has 20K on it with forged pistons and rods. If this was piston slap I would have thought it would have been a problem since the motor was built. Do oil pumps get these types of noises? I would think I would hear it when stehascope was on front cover. Looking for some ideas.... Thanks for your help.
The car is not low on oil. I changed the oil to see if that helped and it did not. I changed the plugs yesterday and all the plugs were dry and looked good. Oil pressure seems normal when warm 25 PSI at idel 65 PSI at higher RPM.
It almost seems it is coming from the front of the engine but putting the stethascope on the front cover the noise is not from within there.
The noise dissapears completely after the engine is at temperature. It does not have the same rythm as the valvetrain.
I was thinking of taking off the serpentine to see if it is generated from an accessory. It is not the water pump or power steering pump as I have listened to both those with the stethascope and the noise isnt there. I Recently did a Mantic Twin-disc clutch upgrade. There were no added weights on the flywheel. I did not match balance the new FW/PP to the previous one but the clutch and drivetrain are vibration free. In fact less vibration than before the clutch upgrade. Car runs fine otherwise. I was leaning towards accessories or a bad plug wire (insulation). I am putting a new set of GM red wires on today.
Motor has 20K on it with forged pistons and rods. If this was piston slap I would have thought it would have been a problem since the motor was built. Do oil pumps get these types of noises? I would think I would hear it when stehascope was on front cover. Looking for some ideas.... Thanks for your help.
Last edited by TwinTurboZ51; 10-02-2014 at 03:52 PM.
10-02-2014, 05:01 PM
#2
Team Owner
"Clicking?" Hmmm, a recording or video would help.
Based on what you're saying my first thought is maybe the A.I.R. pump, which only runs for a few minutes until the engine is up to temp, but I've never heard a "clicking" sound as such. The usually are more likely to make a whining, or "roaring" sound when they are going bad.
Btw, it's located on the driver's side front under and behind the headlight area. It mounts to the "skid frame".
Based on what you're saying my first thought is maybe the A.I.R. pump, which only runs for a few minutes until the engine is up to temp, but I've never heard a "clicking" sound as such. The usually are more likely to make a whining, or "roaring" sound when they are going bad.
Btw, it's located on the driver's side front under and behind the headlight area. It mounts to the "skid frame".
10-02-2014, 05:21 PM
#3
Le Mans Master
Start of a tensioner/pulley going south? I used a long small tube (wife bought a big set of lip glosses in a ~ ø1" x ~ 36" plastic clear tube) to find the source of my problem (chirping, but maybe that's where you're heading?). Ended up being both tensioners.
10-02-2014, 05:25 PM
#4
Team Owner
I wonder how many people will now post up asking where can THEY get one of these, and how much it costs.
10-03-2014, 08:31 PM
#6
Team Owner
Good point. 
10-05-2014, 07:13 AM
#8
Drifting
Member Since: Sep 2009
Location: cinnaminson n.j.
Posts: 1,719
Likes: 0
Received 4 Likes
on
4 Posts
St. Jude Donor '14
Take off the belts and run it. See if the noise is gone. If so, check the balancer, wp and other accessories.
Last edited by martysauto; 10-05-2014 at 07:13 AM. Reason: Auto correct
10-05-2014, 04:38 PM
#10
Instructor
Thread Starter
Member Since: Jan 2011
Location: Buffalo Grove Illinois
Posts: 176
Likes: 0
Received 1 Like
on
1 Post
Ok I have finally pinpointed the noise. It is from the left side idler pulley that is directly above the lower tensioner. It is clicking or chattering when i put the stethescope on the center bolt. Is this idler difficult to change?