Harmonic balancer replacement and engine balance questions
Thread Starter
Instructor
Joined: Nov 2004
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Harmonic balancer replacement and engine balance questions
I saw a video where it was suggested that you need to mark the position of the old balancer, see if it has any weights, move them to the new balancer? I thought all LS motors were internally balanced? If they are indeed internally balanced the flywheel and harmonic balancer would be neutrally balanced. Consequently they can go on in any position and no one should alter the harmonic balancer in any way, i.e. moving weights from the old one to the new one would be a bad idea.
Also, where can I get an aftermarket replacement that would be more durable than stock one? Not looking to change/improve anything, just a more durable replacement for stock.
P. S. I swapped my old 99 from Auto to Manual about a decade ago. I installed a flywheel and clutch from manual car. The engine balance did not appear to be affected in any way, so my experience kind of suggests that these engines are internally balanced. If that engine were externally balanced, swapping flexplate for flywheel would have required rebalancing the engine.
Also, where can I get an aftermarket replacement that would be more durable than stock one? Not looking to change/improve anything, just a more durable replacement for stock.
P. S. I swapped my old 99 from Auto to Manual about a decade ago. I installed a flywheel and clutch from manual car. The engine balance did not appear to be affected in any way, so my experience kind of suggests that these engines are internally balanced. If that engine were externally balanced, swapping flexplate for flywheel would have required rebalancing the engine.
Team Owner
Joined: May 2001
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From: Western NY
I replaced my OE balancer with an ATI balancer, several years ago. While the OE balancer does not have a "keyway" to locate it on the crankshaft, I also purchased the ATI "pinning fixture", which does locate itself off the key slot that's further in, on the crank, therefore it indexes the pulley correctly, to coincide with the timing marks. With respect to vibrations, I haven't noticed any, and my car is a stick shift car, which supposedly had the small "slugs" inserted into the OE balancer, at the factory.
Thread Starter
Instructor
Joined: Nov 2004
Posts: 113
Likes: 2
I replaced my OE balancer with an ATI balancer, several years ago. While the OE balancer does not have a "keyway" to locate it on the crankshaft, I also purchased the ATI "pinning fixture", which does locate itself off the key slot that's further in, on the crank, therefore it indexes the pulley correctly, to coincide with the timing marks. With respect to vibrations, I haven't noticed any, and my car is a stick shift car, which supposedly had the small "slugs" inserted into the OE balancer, at the factory.
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if they were meant to go on in a specific position then the crank would be keyed from the factory... I have had 3 balancers on mine other than the stock one (one an oem replacement, 2 aftermarket) and none of them caused any noticeable vibrations, I personally wouldn't worry about the orientation
Team Owner
Joined: May 2001
Posts: 87,409
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From: Western NY
if they were meant to go on in a specific position then the crank would be keyed from the factory... I have had 3 balancers on mine other than the stock one (one an oem replacement, 2 aftermarket) and none of them caused any noticeable vibrations, I personally wouldn't worry about the orientation
Drifting
Joined: Apr 2010
Posts: 1,479
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From: Jacksonville Florida
I had to replace my harmonic balancer about 3 years ago when the original backed off the crank and into the timing cover. What a mess.
I installed a Powerbond "stock" replacement. It has been used by many on the Forums and YouTube. Price was great and install went very smooth. Been working perfect since install. It failed at 150,000 miles and the car has over 205,000 now. No noticeable vibration. The harmonic balancer has much less effect on potential vibration problems then the clutch pack does. I can't say that it would be a perfect replacement for everyone but it has worked great for me at a great price.
What year is the car your working on now. It seems that not all of the C5s are the same when it comes to balancing issues. I'm going thru an entire drive train refurbish right now. My rear main seal was leaking badly and while I have everything out I'm replacing all wear parts and fixing all leaks as I go through re-assembly. I was so worried about the "match balancing" issue that we read so much about, but, after reading my factory service manual for my '04 Z it directs that you do not match balance the clutch when installing a new clutch. Not sure what other years may be like the 2004.
Good luck and let us know how you make out.
I installed a Powerbond "stock" replacement. It has been used by many on the Forums and YouTube. Price was great and install went very smooth. Been working perfect since install. It failed at 150,000 miles and the car has over 205,000 now. No noticeable vibration. The harmonic balancer has much less effect on potential vibration problems then the clutch pack does. I can't say that it would be a perfect replacement for everyone but it has worked great for me at a great price.
What year is the car your working on now. It seems that not all of the C5s are the same when it comes to balancing issues. I'm going thru an entire drive train refurbish right now. My rear main seal was leaking badly and while I have everything out I'm replacing all wear parts and fixing all leaks as I go through re-assembly. I was so worried about the "match balancing" issue that we read so much about, but, after reading my factory service manual for my '04 Z it directs that you do not match balance the clutch when installing a new clutch. Not sure what other years may be like the 2004.
Good luck and let us know how you make out.
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From: Redondo Beach CA
I don't know about the entire line, but my 03 manual convertible has external weights, and convertibles had the most extensive attention to balance in the line. Hot balance, where the engine is run to balance the thing , I believe, was exclusive to the convertibles.
The front harmonic balancer has no weights to transfer.
The front harmonic balancer has no weights to transfer.
Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
The manual states to mark and transfer the weights (if any) to the new OEM harmonic balancer. Personally, I would at least mark it if going with another brand/type. Then at least you have the information should a problem develop. Without the mark, you are lost. I used an ATI on mine as well when I had the car, never had an issue. I also used the ATI pin kit.
Team Owner
Joined: May 2001
Posts: 87,409
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From: Western NY
The manual states to mark and transfer the weights (if any) to the new OEM harmonic balancer. Personally, I would at least mark it if going with another brand/type. Then at least you have the information should a problem develop. Without the mark, you are lost. I used an ATI on mine as well when I had the car, never had an issue. I also used the ATI pin kit.
I, too, installed and pinned an ATI damper. I used the p/n 917246 damper. I just took a walk out to the garage, to look at my OE damper, which I kept. It has what appears to be one of the "balance slugs" in it. My car is a stick shift coupe, if that means anything.....