Engine Vibration under no load ~1500 rpm- Harmonic Balancer?
02-01-2020, 10:49 PM
#21
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I know it is now 2020 
how ever I want to add to this. My 01 LS1/T56 has this vibration wobble at 1600 rpm when I have the clutch pushed in and holding rpms at 1600. I have poly motor/trans mounts in a FC RX7.Aluminum flywheel, Long tubes, no cats, X pipe and 2 tail pipes. I replaced the crank dampener with a new OEM and it does the same.
how ever I want to add to this. My 01 LS1/T56 has this vibration wobble at 1600 rpm when I have the clutch pushed in and holding rpms at 1600. I have poly motor/trans mounts in a FC RX7.Aluminum flywheel, Long tubes, no cats, X pipe and 2 tail pipes. I replaced the crank dampener with a new OEM and it does the same. 
02-04-2020, 05:20 PM
#22
With 111k miles... Doubtful... Watch the balancer when revving the engine. If its coming apart unload, you should see a wobble to it.
Secondly, I'd get my eyes on the motor mounts. Age wise... I'd be looking at that first. Take a prybar and see if there excessive engine movement. Should not move more than .125 of an inch. You can put your hand on the shock tower to feel vibrations when revving. If nothing. Put hand in intake manifold when revving and you should have a better idea. Chances a weight came off flexplate is slim if you don't hear anything rattling.
good luck
Secondly, I'd get my eyes on the motor mounts. Age wise... I'd be looking at that first. Take a prybar and see if there excessive engine movement. Should not move more than .125 of an inch. You can put your hand on the shock tower to feel vibrations when revving. If nothing. Put hand in intake manifold when revving and you should have a better idea. Chances a weight came off flexplate is slim if you don't hear anything rattling.
good luck
My engine has a bit of a vibration when I keep the rpm at between 1200 and 2000. I notice that in park or neutral it's much more pronounced than when in drive (though I will feel it). Doesn't matter if the car is moving. Now the only thing I see out of the ordinary is my belt tensioner shakes, as if a pulley is out of round. Well everything looks good except the harmonic balancer, which shakes some. Think this may be related? I've had harmonic balancers be not quite perfect on other cars, yet I wouldn't get a symptom like this. How common is it for the LS1 harmonic balancers to come out of round, or shake when rotating? It's all original w/ 111k on it. Thanks in advance for any help.
02-06-2020, 02:31 PM
#23
This threads been bumped more than cocaine in the 80's.
Internal vibration damper? WHAT?
My engine shakes like crazy at idle., actually my whole car shakes lol. I just blame the cam.
Internal vibration damper? WHAT?
My engine shakes like crazy at idle., actually my whole car shakes lol. I just blame the cam.
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G Atsma (02-06-2020)
02-06-2020, 10:28 PM
#24
I finally had my original motor mounts replaced with poly at 175k last month. The grinding noise at idle is gone. It's been replaced with a host of vibrations. It feels like a musclecar - not exactly a problem for me
