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Discussion Starter · #1 ·
I just noticed that the crankshaft pulley has a wobble to it. It's not making any weird noises or anything. I'm not sure when this started. The accessories seem to be running alright still.

What do I need to replace to fix this? Are there some internal bearings? Has anyone ever seen the wobble before? Car has 177k on it. Nothing hit the pulley physically, that I'm aware of, but I did just change the alternator so I took the belt off. I don't remember it doing that when I first put it all back together. Wondering if the change in tension loosened something up.

I did search online and people were saying to just replace the pulley... that seems too easy which is why I figured I'd post and ask.

Car has never been in an accident that I'm aware of
 

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Like this? I replaced it with an ATI superdamper. Not too difficult, you will need tools: flexplate holder, dampener puller, dampener install and torque wrench good to 250 lb ft. Some will say you don't need the tools and there are other options beside the ATI - all your call.
 
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Discussion Starter · #3 ·
Like this? I replaced it with an ATI superdamper. Not too difficult, you will need tools: flexplate holder, dampener puller, dampener install and torque wrench good to 250 lb ft. Some will say you don't need the tools and there are other options beside the ATI - all your call.
Mine is actually worse than that. It's noticeably wobbling. I've been reading up and some people say to replace the pulley and bolt with ARP bolt then torque to 240ft/lb. Others say they just tightened the bolt up and it was good for a while. I might try tightening it down a bit to see if it's loose. Some people with L76/G8 are saying the bolt comes loose that holds the pulley on. I'm wondering if the bigger alternator 170a ACDELCO loosened the bolt due to more resistance
 

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If the dampener has never been off, I doubt it's loose. The pulley is wobbling on the rubber dampening material.

You better hope it's not a loose dampener as it's a press fit on the crank snout. If loose, I suggest the replacement dampener be pinned and bolt tighten to spec. Anything less, it's your call.
 
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Discussion Starter · #5 ·
If the dampener has never been off, I doubt it's loose. The pulley is wobbling on the rubber dampening material.

You better hope it's not a loose dampener as it's a press fit on the crank snout. If loose, I suggest the replacement dampener be pinned and bolt tighten to spec. Anything less, it's your call.
So basically the dampener would need to be replaced? And that requires the engine to be outside the car?
 

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Yes, dampener would require replacement. Typically done with engine in car, no need to pull engine.
 

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Discussion Starter · #7 ·
Yes, dampener would require replacement. Typically done with engine in car, no need to pull engine.
Do you happen to have any links for instructions on how to do that? I've been searching for an hour and I can't find anything on it.

also, see this thread, seems it's pretty common and there's 5 different part numbers for G8 harmonic balancers (or?) crankshaft pulleys due to the design. One guy said his has been to the dealer three times for it

 

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It's relatively common for these motors and everything they put them in. It's not terrible to continue driving with it like that but it can eventually cause belts to break/fly off, or the damper itself coming apart and breaking some things. If it does happen, it will probably happen at higher RPM's. I replaced mine with a 25% underdrive pulley from Summit. Installation was easy with a 1/2" breaker bar and 1/2" torque wrench. Also keep in mind you'll need a different belt size if you go with an underdrive pulley (Summit pulley comes with a list of belt options you will need).
 

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Discussion Starter · #10 ·
It's relatively common for these motors and everything they put them in. It's not terrible to continue driving with it like that but it can eventually cause belts to break/fly off, or the damper itself coming apart and breaking some things. If it does happen, it will probably happen at higher RPM's. I replaced mine with a 25% underdrive pulley from Summit. Installation was easy with a 1/2" breaker bar and 1/2" torque wrench. Also keep in mind you'll need a different belt size if you go with an underdrive pulley (Summit pulley comes with a list of belt options you will need).
thanks for the response. it sounds like from above I might have replace the harmonic balancer which is more involved. I won't be doing an underdrive pulley because I have a 2000.1D amp. I need all the juice I can get. I just put in a 170a alternator so I think I need every bit of drive I can get. I don't really race mine.
 

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Discussion Starter · #11 ·
If the dampener has never been off, I doubt it's loose. The pulley is wobbling on the rubber dampening material.

You better hope it's not a loose dampener as it's a press fit on the crank snout. If loose, I suggest the replacement dampener be pinned and bolt tighten to spec. Anything less, it's your call.
The dampener has never been taken off the car before. If I replace the crankshaft pulley would that fix the rubber you're speaking of? Should I try replacing the pulley and bolt first, torque to spec then see if that fixes issue before I try to replace the dampener?
 

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The accessory pulley and AC pulley are part of the dampener assembly. You have to replace the dampener and the bolt.

Jaw Font Screenshot Automotive tire Rectangle
 
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Discussion Starter · #13 ·
The accessory pulley and AC pulley are part of the dampener assembly. You have to replace the dampener and the bolt.

View attachment 185593
it looks like one bolt but you said there's a few tools I need? It's not as simple as just bolting the new one on? I need to press it onto the snout of the crankshaft? are there any official service manual pages on how to do this? I'm going to start looking around I tried to find one last night and didn't find anything
 

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In addition to the tools I listed, you should get a new front seal for the dampener since you will have it apart. I'm confident you can find instructions/guides for R&R of a LS dampener on the internet. This board, G8nation, Ls1tech, camaro5 or various vette forums should have something.
 
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Discussion Starter · #15 ·
In addition to the tools I listed, you should get a new front seal for the dampener since you will have it apart. I'm confident you can find instructions/guides for R&R of a LS dampener on the internet. This board, G8nation, Ls1tech, camaro5 or various vette forums should have something.
What are your thoughts on this video
(for installation only) .. it's an LS1 though I think. Same procedure?
 

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Discussion Starter · #16 ·
In addition to the tools I listed, you should get a new front seal for the dampener since you will have it apart. I'm confident you can find instructions/guides for R&R of a LS dampener on the internet. This board, G8nation, Ls1tech, camaro5 or various vette forums should have something.
found this video on the removal
.. look about right? I see what you're saying about the tools now, to get it off. Doesn't look too bad really
 

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Discussion Starter · #17 ·
In addition to the tools I listed, you should get a new front seal for the dampener since you will have it apart. I'm confident you can find instructions/guides for R&R of a LS dampener on the internet. This board, G8nation, Ls1tech, camaro5 or various vette forums should have something.
In that installation video I posted above the guy was saying to loosen the timing chain cover. Is that necessary if the motor is already fully assembled? I'd rather not if I don't need to
 

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High level overviews. Neither show how the flexplate is held/locked. you get the idea. Make sure you tighten to spec, none of the uga-uga facebook engineering BS..
 

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In that installation video I posted above the guy was saying to loosen the timing chain cover. Is that necessary if the motor is already fully assembled? I'd rather not if I don't need to
He had the cover off, need to leave it loose to align the seal. Not need for you to remove the cover, pop a new seal in -should be all set.
 
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