Harmonic Balancer fell off
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Intermediate
Joined: Aug 2016
Posts: 26
Likes: 1
Harmonic Balancer fell off
So I just recently bought a c6 back in April and about a week ago I was driving down the highway and a message popped up saying "Service Charging System", it only stayed on for about the same amount of time that I could read it then it went away. I was on my way home and the message popped up again only this time I lost power steering so I pulled over to the side of road looked in the bay and noticed the pulley is sitting against the rack and pinion. Tow her home lift her up take everything out and noticed there was some damage done to the pulley. Now the question here is do I need to replace the entire crankshaft and bearing because of this situation?
Advanced
Joined: Dec 2015
Posts: 52
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I went with the ATI balancer and have been very happy with it so far. The car runs smoothly and no more wobbling. I'm in the DC area and Tony's Corvette Shop installed it for me. It is pinned to the crank. I think GM may have recently updated and tried to improve their design, but I'm not sure. I had ready pretty good reviews about the ATI and went with that.
Thread Starter
Intermediate
Joined: Aug 2016
Posts: 26
Likes: 1
Thread Starter
Intermediate
Joined: Aug 2016
Posts: 26
Likes: 1
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Burning Brakes
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From: Tampa FL
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From: San Diego
Le Mans Master
Joined: May 2016
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From: Florida
The question is - did the pulley itself spin off leaving the core bolted onto the crankshaft end? I guess it might have, BC if the entire HB left the crankshaft while running it would have sounded like a bomb going off and would have launched somewhere doing a lot of damage.
To your question about pinning, this setup does not use a key just a press fit onto the end of the CS. It CAN be pinned though. As others have said, smart to go aftermarket, BC the GM balancers have a pretty high failure rate. I changed mine out to a Powerbond. ATI, as mentioned. is a popular aftermarket replacement as well.
To your question about pinning, this setup does not use a key just a press fit onto the end of the CS. It CAN be pinned though. As others have said, smart to go aftermarket, BC the GM balancers have a pretty high failure rate. I changed mine out to a Powerbond. ATI, as mentioned. is a popular aftermarket replacement as well.
Thread Starter
Intermediate
Joined: Aug 2016
Posts: 26
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The question is - did the pulley itself spin off leaving the core bolted onto the crankshaft end? I guess it might have, BC if the entire HB left the crankshaft while running it would have sounded like a bomb going off and would have launched somewhere doing a lot of damage.
To your question about pinning, this setup does not use a key just a press fit onto the end of the CS. It CAN be pinned though. As others have said, smart to go aftermarket, BC the GM balancers have a pretty high failure rate. I changed mine out to a Powerbond. ATI, as mentioned. is a popular aftermarket replacement as well.
To your question about pinning, this setup does not use a key just a press fit onto the end of the CS. It CAN be pinned though. As others have said, smart to go aftermarket, BC the GM balancers have a pretty high failure rate. I changed mine out to a Powerbond. ATI, as mentioned. is a popular aftermarket replacement as well.
Thread Starter
Intermediate
Joined: Aug 2016
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The entire thing came off like the bolt came forward and it walked right off the CS and up against the rack&pinion. And I was reading another thread where there are 2 different types of ATI balancer one is aluminum and the other one isn't. Would anyone happen to know where I can find the one that is not aluminum?
Burning Brakes
Joined: Aug 2014
Posts: 1,240
Likes: 258
From: Tampa FL
Damper
The entire thing came off like the bolt came forward and it walked right off the CS and up against the rack&pinion. And I was reading another thread where there are 2 different types of ATI balancer one is aluminum and the other one isn't. Would anyone happen to know where I can find the one that is not aluminum?
http://www.jegs.com/webapp/wcs/store...rsistYmm=false
https://www.summitracing.com/parts/ati-917246
It might be that the crank has been harmed by spinning inside Damper. Need to check well! I would use an (ARP) Crank bolt and follow instructions for torque There is a tool to hold flex plate/flywheel found on EBAY.
Last edited by HK770; Aug 29, 2016 at 12:41 PM.
Drifting
Joined: Feb 2012
Posts: 1,428
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From: Brick NJ
You could contact ATI direct at www. atiracing.com or their order line phone # is 877-298-5039
Tech help # 410-298-4343
be sure to get the right balancer you want they have under and overdrive ones available if that's what you want or they have OEM so you won't have to change belt sizes on your car, I would also ask if they have blems available, i paid close to half of the original cost of a ATI balancer by going with a blem, just don't go to Chevy for the balancer they have been known to have problems for some time now, there are also other balancers out there that are good but not as expensive, Powerbond for example etc, I had my balancer replaced with an ATI unit, East Coast Supercharging did mine, a well known Chevy builder in my area and i asked them about pinning the crank, I was told that unless i had plans to add a supercharger to the car it wan't necessary to pin the crank, in my case i know i never will so i did not have them pin the crank and 5000 miles later still no problems, also be sure to get a new crank bolt with the installation and a new front timing cover seal while they are in there. JMO
Tech help # 410-298-4343
be sure to get the right balancer you want they have under and overdrive ones available if that's what you want or they have OEM so you won't have to change belt sizes on your car, I would also ask if they have blems available, i paid close to half of the original cost of a ATI balancer by going with a blem, just don't go to Chevy for the balancer they have been known to have problems for some time now, there are also other balancers out there that are good but not as expensive, Powerbond for example etc, I had my balancer replaced with an ATI unit, East Coast Supercharging did mine, a well known Chevy builder in my area and i asked them about pinning the crank, I was told that unless i had plans to add a supercharger to the car it wan't necessary to pin the crank, in my case i know i never will so i did not have them pin the crank and 5000 miles later still no problems, also be sure to get a new crank bolt with the installation and a new front timing cover seal while they are in there. JMO
Thread Starter
Intermediate
Joined: Aug 2016
Posts: 26
Likes: 1
Yes the end of the crank looks like it has spun on the inside of the damper a little bit and I'm wondering if I will need to replace the crank because of it. I have no problem with getting tools it's just good location for parts and which parts are recommended
Last edited by Kyle Michael; Aug 29, 2016 at 04:44 PM.
Thread Starter
Intermediate
Joined: Aug 2016
Posts: 26
Likes: 1
You could contact ATI direct at www. atiracing.com or their order line phone # is 877-298-5039
Tech help # 410-298-4343
be sure to get the right balancer you want they have under and overdrive ones available if that's what you want or they have OEM so you won't have to change belt sizes on your car, I would also ask if they have blems available, i paid close to half of the original cost of a ATI balancer by going with a blem, just don't go to Chevy for the balancer they have been known to have problems for some time now, there are also other balancers out there that are good but not as expensive, Powerbond for example etc, I had my balancer replaced with an ATI unit, East Coast Supercharging did mine, a well known Chevy builder in my area and i asked them about pinning the crank, I was told that unless i had plans to add a supercharger to the car it wan't necessary to pin the crank, in my case i know i never will so i did not have them pin the crank and 5000 miles later still no problems, also be sure to get a new crank bolt with the installation and a new front timing cover seal while they are in there. JMO
Tech help # 410-298-4343
be sure to get the right balancer you want they have under and overdrive ones available if that's what you want or they have OEM so you won't have to change belt sizes on your car, I would also ask if they have blems available, i paid close to half of the original cost of a ATI balancer by going with a blem, just don't go to Chevy for the balancer they have been known to have problems for some time now, there are also other balancers out there that are good but not as expensive, Powerbond for example etc, I had my balancer replaced with an ATI unit, East Coast Supercharging did mine, a well known Chevy builder in my area and i asked them about pinning the crank, I was told that unless i had plans to add a supercharger to the car it wan't necessary to pin the crank, in my case i know i never will so i did not have them pin the crank and 5000 miles later still no problems, also be sure to get a new crank bolt with the installation and a new front timing cover seal while they are in there. JMO
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Photo's would help to see the extent of the damage and what also may need to be replaced,
But, would go with his HB, isntead of a ATI unit.
http://www.daycoproducts.com/part?ca...ber%3DPB1117SS
As for what is needed,
The HB, a new Oem HB bolt and diamond washer, loctite, new front timing chain cover seal for the HB, a HB install tool, and flywheel lock to hold the crank from turning as you are tightening the HB bolt to spec.
The low down, you need to get the steering rack out of the way. Some have had good luck with just unbolting it and raising it up, while other lower the engine cradle so you can remove it from passager wheel well side (if you loose the engine cradle, you will need to have the front end realigned).
Once have the needed room to work for the bolt.
Start with removing the old seal from the front of the timing chain cover for the HB and install the new seal.
On the HB, do not use the crank bolt to draw the HB on to the crank!!! use a HB install tool to draw the HB onto the crank instead. The HB install tool allows for the entire threads of the crank to be used for support, and the HB is drawn onto the crack via the threads on the tools to prevent the threads in the crank from stripping out.
Once the HB drawn into place on the crank via the HB install tool and the tool removed, use some RTV to fill the crank key slot, but don't flood the slot to flow RTV out the back side of the crank slot isntead.
Now New HB retainer bolt with washer is installed with loctite and the starter removed with a flywheel lock so the crank will not turn,
Regarding the steering shaft, don't spin the steering wheel when you remove the steering column coupling from it to move the steering rake out of the way. In side the steering wheel column is a steering wheel sensor, and if the coupling is not installed back on the shaft the same none rotation shaft position, the steering wheel sensor will not read correctly.
But, would go with his HB, isntead of a ATI unit.
http://www.daycoproducts.com/part?ca...ber%3DPB1117SS
As for what is needed,
The HB, a new Oem HB bolt and diamond washer, loctite, new front timing chain cover seal for the HB, a HB install tool, and flywheel lock to hold the crank from turning as you are tightening the HB bolt to spec.
The low down, you need to get the steering rack out of the way. Some have had good luck with just unbolting it and raising it up, while other lower the engine cradle so you can remove it from passager wheel well side (if you loose the engine cradle, you will need to have the front end realigned).
Once have the needed room to work for the bolt.
Start with removing the old seal from the front of the timing chain cover for the HB and install the new seal.
On the HB, do not use the crank bolt to draw the HB on to the crank!!! use a HB install tool to draw the HB onto the crank instead. The HB install tool allows for the entire threads of the crank to be used for support, and the HB is drawn onto the crack via the threads on the tools to prevent the threads in the crank from stripping out.
Once the HB drawn into place on the crank via the HB install tool and the tool removed, use some RTV to fill the crank key slot, but don't flood the slot to flow RTV out the back side of the crank slot isntead.
Now New HB retainer bolt with washer is installed with loctite and the starter removed with a flywheel lock so the crank will not turn,
Coat the three to five threads of the new bolt with thread locker (LOCKTITE™ 272) P/N 12345493 before installation.
Notice: Be sure to follow the torque procedure for installing the new crankshaft bolt. Use of impact tools, or not using torque and angle method will result in joint failure.
Install and tighten the new crankshaft bolt.
• Tighten the crankshaft balancer bolt a first pass.
Tighten
Tighten the crankshaft balancer bolt a first pass to 50N•m (37 lb ft).
Put a paint stripe on the bolt running from the 12 o'clock to the 6 o'clock position in order to verify the correct torque requested in the next step.
• Important: When tightening for the second pass, a minimum torque of 320 N•m (236 lb ft) should be observed. If this torque is not achieved, the bolt should be replaced.
Tighten the crankshaft balancer bolt a second pass.
Tighten
Tighten the crankshaft balancer bolt a second pass to 140 degrees using the J 45059.
Important: Recheck the position of the previously painted stripe to assure 140 degree rotation. Achieving the correct torque angle is critical to the success of this repair. Over-torquing or under-torquing the joint will result in an unsatisfactory repair.
Remove the J 42386-A Flywheel Holding Tool.
Install the starter and bolts. Tighten the starter bolts.
Tighten
Tighten the starter bolts to 50 N•m (37 lb ft).
Important: Orient the purple lead wire to the 10 o'clock position when installing.
Connect the starter wiring.
Install the starter motor S terminal washer and purple lead wire (1).
Install the S terminal nut (2) and tighten.
Tighten
Tighten the S terminal nut to 4 N•m (35 lb in).
Important: Orient the gray and rust harness leads to the 6 o'clock and 7 o'clock position.
Install the gray and rust harness leads to the solenoid.
Raise and align the cradle.
Install and tighten the cradle nuts.
Tighten
Tighten the nuts, using hand tools only, to 110 N•m(81 lb ft).
Install and tighten the engine mount nuts.
Tighten
Tighten the nuts to 65 N•m(48 lb ft).
Install the A/C belt.
Install the cooler line bolts.
Install the fan shroud assembly and bolts.
Tighten
Tighten the bolts to 5 N•m(44 lb in).
Position the stabilizer shaft and install insulator clamps and bolts.
Tighten
Tighten the stabilizer shaft insulator clamp bolts to 58N•m (43 lb ft).
Install the tie rod to the steering knuckle.
Install the outer tie rod end stud nut to the outer tie rod end stud and tighten .
Tighten
Tighten the outer tie rod end stud nut to 20 N•m(15 lb ft) to seat the stud.
Turn the nut an additional 160 degrees.
Check for the outer tie rod end stud nut for a minimum final torque of 45 N•m(33 lb ft).
Install the lower ball joint to the steering knuckle.
Tighten the lower control arm ball joint stud nut.
Tighten
Tighten the nut to 20 N•m (15 lb ft) to seat the ball joint stud.
Turn the ball joint stud nut an additional 210 degrees.
Check the ball joint stud nut for a minimum final torque of 55 N•m (41 lb ft).
Install the shock bolts and tighten.
Tighten
Tighten the shock absorber lower mounting nuts to 28 N•m (21 lb ft).
Repeat tie rod, lower ball joint and shock for the other side.
Install the tires and lug nuts.
Important: Tighten the nuts evenly and alternately in order to avoid excessive run out of the tire and wheel assembly.
Using the J 39544-KIT , tighten the wheel nuts in the appropriate sequence shown.
Tighten
Tighten the nuts in sequence to 140 N•m(100 lb ft).
Remove the support jack.
Remove the Leaf Spring Compressor (J 33432-A).
Lower the vehicle.
Remove the engine support fixture.
Remove the engine support links.
Install the upper radiator support and tighten the bolts.
Tighten
Tighten the bolts to 9 N•m (80 lb in).
Install the coolant and EVAP lines to the fan shroud.
Install the engine cover and oil fill cap.
Install the intermediate shaft.
LOCTITE™ the steering intermediate shaft bolts and install.
Tighten
Tighten the lower coupling retaining bolt to 34 N•m (25 lb ft).
Install the generator and tighten the bolts.
Tighten
Tighten the generator bolts to 50 N•m(37 lb ft).
Connect the generator wiring.
Tighten
Tighten the battery feed cable nut to 13 N•m(10 lb ft).
Install the new accessory belt.
Install the air duct and box.
Connect the battery cable to the battery.
Perform a crankshaft variation relearn procedure.
Parts Information
Order a washer from the WPC using the form at the end of this bulletin. Fax the request form to the WPC at 248-371-0192, or E-mail to warrantypartscenterusa@gm.com .
All other parts should be ordered from GMSPO. Use the normal ordering process for all orders.
Warranty Parts Center Parts WPC Part Number
Description
Qty
305
Washer, Crankshaft Balancer
1
GMSPO Parts Part Number
Description
Qty
12557840
Bolt, Crankshaft Harmonic Balancer
1
12583637
Balancer, Crankshaft Harmonic
1
12579229
Belt, Water Pump, Power Steering and Generator
1 as req'd
12579228
Belt, Air Conditioning Compressor
1 as req'd
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
J0710
Pulley, Crankshaft Balancer - Replace
2.3 hrs
Notice: Be sure to follow the torque procedure for installing the new crankshaft bolt. Use of impact tools, or not using torque and angle method will result in joint failure.
Install and tighten the new crankshaft bolt.
• Tighten the crankshaft balancer bolt a first pass.
Tighten
Tighten the crankshaft balancer bolt a first pass to 50N•m (37 lb ft).
Put a paint stripe on the bolt running from the 12 o'clock to the 6 o'clock position in order to verify the correct torque requested in the next step.
• Important: When tightening for the second pass, a minimum torque of 320 N•m (236 lb ft) should be observed. If this torque is not achieved, the bolt should be replaced.
Tighten the crankshaft balancer bolt a second pass.
Tighten
Tighten the crankshaft balancer bolt a second pass to 140 degrees using the J 45059.
Important: Recheck the position of the previously painted stripe to assure 140 degree rotation. Achieving the correct torque angle is critical to the success of this repair. Over-torquing or under-torquing the joint will result in an unsatisfactory repair.
Remove the J 42386-A Flywheel Holding Tool.
Install the starter and bolts. Tighten the starter bolts.
Tighten
Tighten the starter bolts to 50 N•m (37 lb ft).
Important: Orient the purple lead wire to the 10 o'clock position when installing.
Connect the starter wiring.
Install the starter motor S terminal washer and purple lead wire (1).
Install the S terminal nut (2) and tighten.
Tighten
Tighten the S terminal nut to 4 N•m (35 lb in).
Important: Orient the gray and rust harness leads to the 6 o'clock and 7 o'clock position.
Install the gray and rust harness leads to the solenoid.
Raise and align the cradle.
Install and tighten the cradle nuts.
Tighten
Tighten the nuts, using hand tools only, to 110 N•m(81 lb ft).
Install and tighten the engine mount nuts.
Tighten
Tighten the nuts to 65 N•m(48 lb ft).
Install the A/C belt.
Install the cooler line bolts.
Install the fan shroud assembly and bolts.
Tighten
Tighten the bolts to 5 N•m(44 lb in).
Position the stabilizer shaft and install insulator clamps and bolts.
Tighten
Tighten the stabilizer shaft insulator clamp bolts to 58N•m (43 lb ft).
Install the tie rod to the steering knuckle.
Install the outer tie rod end stud nut to the outer tie rod end stud and tighten .
Tighten
Tighten the outer tie rod end stud nut to 20 N•m(15 lb ft) to seat the stud.
Turn the nut an additional 160 degrees.
Check for the outer tie rod end stud nut for a minimum final torque of 45 N•m(33 lb ft).
Install the lower ball joint to the steering knuckle.
Tighten the lower control arm ball joint stud nut.
Tighten
Tighten the nut to 20 N•m (15 lb ft) to seat the ball joint stud.
Turn the ball joint stud nut an additional 210 degrees.
Check the ball joint stud nut for a minimum final torque of 55 N•m (41 lb ft).
Install the shock bolts and tighten.
Tighten
Tighten the shock absorber lower mounting nuts to 28 N•m (21 lb ft).
Repeat tie rod, lower ball joint and shock for the other side.
Install the tires and lug nuts.
Important: Tighten the nuts evenly and alternately in order to avoid excessive run out of the tire and wheel assembly.
Using the J 39544-KIT , tighten the wheel nuts in the appropriate sequence shown.
Tighten
Tighten the nuts in sequence to 140 N•m(100 lb ft).
Remove the support jack.
Remove the Leaf Spring Compressor (J 33432-A).
Lower the vehicle.
Remove the engine support fixture.
Remove the engine support links.
Install the upper radiator support and tighten the bolts.
Tighten
Tighten the bolts to 9 N•m (80 lb in).
Install the coolant and EVAP lines to the fan shroud.
Install the engine cover and oil fill cap.
Install the intermediate shaft.
LOCTITE™ the steering intermediate shaft bolts and install.
Tighten
Tighten the lower coupling retaining bolt to 34 N•m (25 lb ft).
Install the generator and tighten the bolts.
Tighten
Tighten the generator bolts to 50 N•m(37 lb ft).
Connect the generator wiring.
Tighten
Tighten the battery feed cable nut to 13 N•m(10 lb ft).
Install the new accessory belt.
Install the air duct and box.
Connect the battery cable to the battery.
Perform a crankshaft variation relearn procedure.
Parts Information
Order a washer from the WPC using the form at the end of this bulletin. Fax the request form to the WPC at 248-371-0192, or E-mail to warrantypartscenterusa@gm.com .
All other parts should be ordered from GMSPO. Use the normal ordering process for all orders.
Warranty Parts Center Parts WPC Part Number
Description
Qty
305
Washer, Crankshaft Balancer
1
GMSPO Parts Part Number
Description
Qty
12557840
Bolt, Crankshaft Harmonic Balancer
1
12583637
Balancer, Crankshaft Harmonic
1
12579229
Belt, Water Pump, Power Steering and Generator
1 as req'd
12579228
Belt, Air Conditioning Compressor
1 as req'd
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
J0710
Pulley, Crankshaft Balancer - Replace
2.3 hrs
Regarding the steering shaft, don't spin the steering wheel when you remove the steering column coupling from it to move the steering rake out of the way. In side the steering wheel column is a steering wheel sensor, and if the coupling is not installed back on the shaft the same none rotation shaft position, the steering wheel sensor will not read correctly.
Last edited by Dano523; Aug 29, 2016 at 05:29 PM.
Drifting
Joined: Feb 2012
Posts: 1,428
Likes: 113
From: Brick NJ
$3500.00 to replace a balancer is incredibly over priced, ECS charged me around $700.00 and that included a new bolt, timing chain cover seal, a new serpentine and A/C belt and i also had them replace the rear differential fluid while it was in there, i supplied the ATI balancer as i said i got a blem at a good price, most people on the forum have said it usually runs around $11-$1200.00 with them supplying all the parts, Hopefully you don't have to replace the crank.
Thread Starter
Intermediate
Joined: Aug 2016
Posts: 26
Likes: 1
Okay so I just spent the last 4 hours taking everything out and I have uploaded pictures in my album section if you guys can go check on the. From what I see the crank has very little damage to it but the HB is pretty bad.