harmonic balancer weighted?
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From: Calgary Alberta
harmonic balancer weighted?
I noticed one weight pin in my harmonic balancer after I took it off, and this got me thinking, are these balanced for the motor? as in i should have marked its original position, or is the balancer just balanced on its own?
The car is a manual.
I'm interested to know, because I have zero way to know of how it was orientated on the crank before I pulled it, yet none of the cam install notes mention marking the balancer.... but all the small block stuff I do is keyed so you don't worry about it. Hmmmm
wish I had of been thinking and scribbed it anyways.
The car is a manual.
I'm interested to know, because I have zero way to know of how it was orientated on the crank before I pulled it, yet none of the cam install notes mention marking the balancer.... but all the small block stuff I do is keyed so you don't worry about it. Hmmmm
wish I had of been thinking and scribbed it anyways.
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C6 of Year Finalist (performance mods) 2019
I noticed one weight pin in my harmonic balancer after I took it off, and this got me thinking, are these balanced for the motor? as in i should have marked its original position, or is the balancer just balanced on its own?
The car is a manual.
I'm interested to know, because I have zero way to know of how it was orientated on the crank before I pulled it, yet none of the cam install notes mention marking the balancer.... but all the small block stuff I do is keyed so you don't worry about it. Hmmmm
wish I had of been thinking and scribbed it anyways.
The car is a manual.
I'm interested to know, because I have zero way to know of how it was orientated on the crank before I pulled it, yet none of the cam install notes mention marking the balancer.... but all the small block stuff I do is keyed so you don't worry about it. Hmmmm
wish I had of been thinking and scribbed it anyways.
Sure hope you get lucky putting it together.
Melting Slicks
Joined: Sep 2009
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So, how does the GM service department get a new balancer synced up with your engine when it needs replacing? Are the balance weights the last step in balancing the engines rotating assembly at the factory?
If this was an issue, I would think the crank pully/balancer would be pinned from the factory.
If this was an issue, I would think the crank pully/balancer would be pinned from the factory.
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From: Phila Suburbs 2023 C8 & 2013 650ix
Again from the 05 Service Manual:
I guess the good news is that you had only one balance weight in the balancer so the system was "almost" in balance without any weights. I'd just take out the one balance weight and put it back together.
I guess the good news is that you had only one balance weight in the balancer so the system was "almost" in balance without any weights. I'd just take out the one balance weight and put it back together.
Last edited by Walt White Coupe; Apr 5, 2011 at 10:48 AM.
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From: Calgary Alberta
This makes no sense. What do you do if your bolt came loose and the balancer spun like on so many of the 05's????? How's the dealership re-istal those? If this is correct the engine would need to be pulled and balanced.
In all of the cam instal threads nobody has mentioned this, is it just so known or does nobody do it or think about it?
Yes I know the service manual says to scribe it, but if you run a aftermarket balancer what do you do???
So what are my options boys? Car's getting torn apart again
, I'm not running a un-balanced set-up. Who has a centrfically balanced balancer?
In all of the cam instal threads nobody has mentioned this, is it just so known or does nobody do it or think about it?
Yes I know the service manual says to scribe it, but if you run a aftermarket balancer what do you do???
So what are my options boys? Car's getting torn apart again
, I'm not running a un-balanced set-up. Who has a centrfically balanced balancer?
Last edited by Phill25; Apr 5, 2011 at 11:23 AM.
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From: Phila Suburbs 2023 C8 & 2013 650ix
The balance weights are not to balance the harmonic balancer. They are put in to balance the entire rotating crank assembly. Short of balancing that rotating assembly the way they do during initial engine assembly (and I have no idea how they actually do it) you have to live with the "possibility" of slight unbalance.
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Thread Starter
Instructor
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From: Calgary Alberta
The balance weights are not to balance the harmonic balancer. They are put in to balance the entire rotating crank assembly. Short of balancing that rotating assembly the way they do during initial engine assembly (and I have no idea how they actually do it) you have to live with the "possibility" of slight unbalance.
. How do people switching to underdrives balance their set-ups then? I have a feeling the single .5 oz weight is getting tossed and if I wreck the motor (crank bearings, oil pump or timing chain) I will just build a 427. 
Melting Slicks
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Anyone had to buy a GM replacement balancer with weights already installed? If so, it would lead me to believe the balancer is balanced separate from the rotating assembly. I would find it hard to believe that the weights are added as part of a "whole rotating assemby" balance process. Especially since the engineers should have incorporated a crank pinning or key system to ensure the balancer could not slip.
Just my opinion, FWIW.
Just my opinion, FWIW.
Drifting
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From: STL MO
St. Jude Donor '09-'10
Look up the ATI Superdamper, I believe it will balance itself to your rotating assembly (something like that)
I wasn't willing to roll the dice and put the stock balancer back on after reading to many threads about people having issues in the year range of my car.
I chose to go with the Powerbond 10% UD crank pulley based on price and SFI approval.
It is a nice piece and I finally have a crank pulley that spins perfectly true instead of one with a little wobble!
I wasn't willing to roll the dice and put the stock balancer back on after reading to many threads about people having issues in the year range of my car.
I chose to go with the Powerbond 10% UD crank pulley based on price and SFI approval.
It is a nice piece and I finally have a crank pulley that spins perfectly true instead of one with a little wobble!
Race Director
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From: Phila Suburbs 2023 C8 & 2013 650ix
Anyone had to buy a GM replacement balancer with weights already installed? If so, it would lead me to believe the balancer is balanced separate from the rotating assembly. I would find it hard to believe that the weights are added as part of a "whole rotating assemby" balance process. Especially since the engineers should have incorporated a crank pinning or key system to ensure the balancer could not slip.
Just my opinion, FWIW.
Just my opinion, FWIW.
Le Mans Master
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From: West coast CA
Anyone had to buy a GM replacement balancer with weights already installed? If so, it would lead me to believe the balancer is balanced separate from the rotating assembly. I would find it hard to believe that the weights are added as part of a "whole rotating assemby" balance process. Especially since the engineers should have incorporated a crank pinning or key system to ensure the balancer could not slip.
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From: Calgary Alberta
LOL!!! I should have started a poll!! 
So we have people agreeing with the service manual that the balancer is balanced to the rotating assembly and people saying its just balanced to itself.
I called a few notable shops... all said they don't scribe, they simply re-install in whatever orientation and pin it. Not that this is correct but it seems to do the trick.
Also, like stated, the aftermarket non-centrifical units are made based on the theory that the engine is internally balanced. Sooooo
I think I will just dig my one little weight out....
So we have people agreeing with the service manual that the balancer is balanced to the rotating assembly and people saying its just balanced to itself.
I called a few notable shops... all said they don't scribe, they simply re-install in whatever orientation and pin it. Not that this is correct but it seems to do the trick.
Also, like stated, the aftermarket non-centrifical units are made based on the theory that the engine is internally balanced. Sooooo
I think I will just dig my one little weight out....
Melting Slicks
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Interesting that the service manual implies it is only necessary on manual trans cars. What about automatics?
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From: Phila Suburbs 2023 C8 & 2013 650ix
It must have something to do with the difference between the crankshaft being connected to relatively heavy flywheel/clutch/pressure plate in the stick and the torque converter in the automatic. The torsional vibrational systems are obviously different but how that relates to the harmonic balancer, I don't know.
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From: Calgary Alberta
I ended up not bothering to pull the one weight after talking to more experts. put the car back together and had her to redline today, smooth as silk.
even talked to a GM tech, he said the dealer's never scribe balacers.
If i was doing it from scratch I would for peace of mind, but really don't think its needed at this point.
Just a update for anyone searching.
even talked to a GM tech, he said the dealer's never scribe balacers.
If i was doing it from scratch I would for peace of mind, but really don't think its needed at this point.
Just a update for anyone searching.
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From: Phila Suburbs 2023 C8 & 2013 650ix
even talked to a GM tech, he said the dealer's never scribe balacers.
Just shows how incompetent they are. Not how smart. And what makes you think you could feel a torsional imbalance from the seat of your mark 4 pants?
Just shows how incompetent they are. Not how smart. And what makes you think you could feel a torsional imbalance from the seat of your mark 4 pants?
Last edited by Walt White Coupe; Apr 7, 2011 at 08:08 AM.
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C6 of Year Finalist (performance mods) 2019
LOL!!! I should have started a poll!!
So we have people agreeing with the service manual that the balancer is balanced to the rotating assembly and people saying its just balanced to itself.
I called a few notable shops... all said they don't scribe, they simply re-install in whatever orientation and pin it. Not that this is correct but it seems to do the trick.
Also, like stated, the aftermarket non-centrifical units are made based on the theory that the engine is internally balanced. Sooooo
I think I will just dig my one little weight out....
So we have people agreeing with the service manual that the balancer is balanced to the rotating assembly and people saying its just balanced to itself.
I called a few notable shops... all said they don't scribe, they simply re-install in whatever orientation and pin it. Not that this is correct but it seems to do the trick.
Also, like stated, the aftermarket non-centrifical units are made based on the theory that the engine is internally balanced. Sooooo
I think I will just dig my one little weight out....
I have no clue how GM would suggest replacing a pulley assembly that has spun on the crank.