Harmonic balancer replacement advice
Thread Starter
Pro
Joined: Aug 2000
Posts: 517
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From: Arlington Texas
Harmonic balancer replacement advice
I have a wobbling balancer and want to replace it. I suppose I'll go ahead and put on an underdrive pulley, but I have a few questions. First, does anyone know if I can buy one from a store in the Dallas area, or do I have to order/ship it. Second, do I really want to do this myself or let a pro do it? I'm not a complete idiot with a wrench, but it sounds like the original is a pain to remove, and I don't know what's involved in pinning or keying the new one. Thanks.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
The original is not pinned, so if you just do a one for one replacement you won't need to pin it. An underdrive can yield a few HP if you want to go that route. I went with the ATI, which is rebuildable as well. The hub is already keyed to receive a pin and they have a pin kit that is all inclusive and easy to use.
You will need to remove the power steering rack to get at it. If you need to change the coolant, you might also consider dropping out the water pump so all the coolant dumps and you have better access. Take a look at the cam swap on LS1Howto.com to see what is involved.
You will need to remove the power steering rack to get at it. If you need to change the coolant, you might also consider dropping out the water pump so all the coolant dumps and you have better access. Take a look at the cam swap on LS1Howto.com to see what is involved.
Racer
Joined: Jun 2004
Posts: 421
Likes: 0
From: Dallas Texas
I'm not sure if there's a place local that stocks them, I had to order one from MTI because ThunderRacing was out at the time. Texas Speed and Performance had a different brand of one on sale not too long ago.
Pinning and Keying is a requirement for a car with a supercharger, not N/A.
If there's a two piece timing cover on the market that doesn't leak, you might think about adding this while you have to take out the steering to cut down on labor of a cam change, I wish I would have.
Pinning and Keying is a requirement for a car with a supercharger, not N/A.
If there's a two piece timing cover on the market that doesn't leak, you might think about adding this while you have to take out the steering to cut down on labor of a cam change, I wish I would have.
Burning Brakes
Joined: Aug 2000
Posts: 889
Likes: 0
From: DFW tx
It is no easy task. Getting the pulley off is a pain, but not too bad. Putting the new pulley on is the hardest part. You have to put 250 ft/lbs to seat the pulley, then you need to use a new bolt and torque it down, then angle torque it. Quite a few people mess this step up, stripping crank threads, etc.
GM makes a tool to seat the pulley (as opposed to using the bolt and crank threads to do the work). And you will probably need a flywheel locking tool even if you have a 6 speed. 250 ft/lbs is a lot of torque and it can turn the wheels.
If you are going to do it yourself, I would look into pinning the crank. Many people (including me) have had the pulleys start to come off. Luckily I caught mine after the a/c belt shredded and before it spun off all the way.
GM makes a tool to seat the pulley (as opposed to using the bolt and crank threads to do the work). And you will probably need a flywheel locking tool even if you have a 6 speed. 250 ft/lbs is a lot of torque and it can turn the wheels.
If you are going to do it yourself, I would look into pinning the crank. Many people (including me) have had the pulleys start to come off. Luckily I caught mine after the a/c belt shredded and before it spun off all the way.
Thread Starter
Pro
Joined: Aug 2000
Posts: 517
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From: Arlington Texas
What are my options for pinning the damper on the crank? Is the ATI kit the only thing out there? If so, does it work on non-ATI dampers? I understand pinning might be overkill for street use, but if I'm there already I'll go ahead and do it if it's not too much trouble/expense.
Has anyone had a bad experience with underdrive pulleys? Should I just stay stock diameter?
Has anyone had a bad experience with underdrive pulleys? Should I just stay stock diameter?
Drifting
Joined: Feb 2005
Posts: 1,960
Likes: 0
From: Issaquah Wa.
snap-on,....or craftsman sell a "gear puller" that will make this otherwise very difficult job a whole lot simpler and I would not put the stock part back on I mean there is just so much realy 
stuff out there! 
check all the "usual suspects" Jegs,.....ecklers,....or mid america!
stuff out there! check all the "usual suspects" Jegs,.....ecklers,....or mid america!
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Team Owner
Joined: Mar 1999
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From: At the beach in little Rhody
I pinned mine, and I am not FI. I also went to the ARP bolt, which is installed with Moly lube so no fear of later removal. The ATI is a very high quality unit and is rebuildable. Others are available but the pin kit you use may also depend on if they are keyed. If they are not keyed, you will have to do an end pin if you decide to pin the balancer or you will have to get the balancer machined for a key if you use the ATI kit.
Melting Slicks
Joined: Sep 2005
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From: merritt island fl
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My pulley is starting to wobble so I guess I should be thinking about replacing the harmonic balanceron my 2001. I'm confused by the various sizes and types (internal or external weights) available. What do I need for a stock, daily driver? Seems that the OEM is no good, so why replace it with another OEM? Also, where do I get a flywheel lock for doing the job on an A4?
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Originally Posted by dave pawlowski
My pulley is starting to wobble so I guess I should be thinking about replacing the harmonic balanceron my 2001. I'm confused by the various sizes and types (internal or external weights) available. What do I need for a stock, daily driver? Seems that the OEM is no good, so why replace it with another OEM? Also, where do I get a flywheel lock for doing the job on an A4?
So IF you have them mark the relationship of the balancer to crank and your new one must be installed in this manner.
As far as OEM vs aftermarket (ATI), I don't ever remember anyone complaining they bought the best of anything!
Do key the crank even for street use! And a good 1/2" impact will remove your balancer bolt w/o a flywheel lock, and reinstall it with the same using red loctite to 150 ftlbs using a NEW bolt (I used ARP 12 point). And be done with the problem forever!
Tip: I bought some threaded stock from a fastner store with the right metric thread and cut it a couple inches longer then the stock bolt and using a thick flat washer and nut draw it down tight against the timing gear before installing the new bolt.
Melting Slicks
Joined: Sep 2005
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From: merritt island fl
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Thanks for the reply but 2 questions remain:
1. What size balancer do I need?
2. How do you get 150 ft-lbs without locking the flywheel?
1. What size balancer do I need?
2. How do you get 150 ft-lbs without locking the flywheel?
Originally Posted by corvettebob1
MOST engines used a zero balanced damper but check yours for weights (pressed in pins near the OD on the outer ring). If you have them they must be transferred to the new damper or it must be balanced the same way.
So IF you have them mark the relationship of the balancer to crank and your new one must be installed in this manner.
As far as OEM vs aftermarket (ATI), I don't ever remember anyone complaining they bought the best of anything!
Do key the crank even for street use! And a good 1/2" impact will remove your balancer bolt w/o a flywheel lock, and reinstall it with the same using red loctite to 150 ftlbs using a NEW bolt (I used ARP 12 point). And be done with the problem forever!
Tip: I bought some threaded stock from a fastner store with the right metric thread and cut it a couple inches longer then the stock bolt and using a thick flat washer and nut draw it down tight against the timing gear before installing the new bolt.
So IF you have them mark the relationship of the balancer to crank and your new one must be installed in this manner.
As far as OEM vs aftermarket (ATI), I don't ever remember anyone complaining they bought the best of anything!
Do key the crank even for street use! And a good 1/2" impact will remove your balancer bolt w/o a flywheel lock, and reinstall it with the same using red loctite to 150 ftlbs using a NEW bolt (I used ARP 12 point). And be done with the problem forever!
Tip: I bought some threaded stock from a fastner store with the right metric thread and cut it a couple inches longer then the stock bolt and using a thick flat washer and nut draw it down tight against the timing gear before installing the new bolt.
Premium Supporting Vendor
Joined: Dec 1999
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From: Texas Speed TX
I have the Powerbond & ASP pulleys in stock! Our ground UPS will have it to you overnight so you can install it by Tuesday! 
Feel free to call or IM me if I can help!
Jason
Texas Speed
www.texas-speed.com
Feel free to call or IM me if I can help!Jason
Texas Speed
www.texas-speed.com
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Originally Posted by dave pawlowski
Thanks for the reply but 2 questions remain:
1. What size balancer do I need?
2. How do you get 150 ft-lbs without locking the flywheel?
1. What size balancer do I need?
2. How do you get 150 ft-lbs without locking the flywheel?
2. Any good air 1/2" impact gun will easely get 150 ft-lbs and more when used on a 3/8-1/2" air line. I have 2 one is a CP-735 rated at 200 ft-lbs and a CP-740 rated at 250 ft-lbs. (I used to use them to crush the sleeve in GM 10 & 12 bolt pinions.)
Safety Car
Joined: Jun 2003
Posts: 4,510
Likes: 240
From: Coconut Creek FL
Just had mine replaced...used an ASP pulley from summit racing $209 + shipping (best price I could find)
http://store.summitracing.com/defaul...h.asp&x=28&y=5
had the shop do all the work as the steering rack has to come out...got a stock GM bolt to replace as well.
I believe it is 25% underdrive for the main belt and 10% for the AC. I have no issues with charging and the wabble is gone...so is the engine vibration I had with the old one...
Also had the shop pin the new install to make sure it never backs off..figure a shop to take 4 hours labor...
some things the pros should do!
http://store.summitracing.com/defaul...h.asp&x=28&y=5
had the shop do all the work as the steering rack has to come out...got a stock GM bolt to replace as well.
I believe it is 25% underdrive for the main belt and 10% for the AC. I have no issues with charging and the wabble is gone...so is the engine vibration I had with the old one...
Also had the shop pin the new install to make sure it never backs off..figure a shop to take 4 hours labor...
some things the pros should do!
Intermediate
Joined: Dec 2005
Posts: 39
Likes: 0
Unless you have some serious tools I would not recommend this for the do it yourselfer. I am rebuilding the engine in my 99 C5 and put the engine back in the car without putting the balancer back on first by mistake. You'll have to remove the rack and pinion in order to make the exchange. Also, I broke an impact socket getting the original bolt off, and to install it properly you'll need to come up with a long metric threaded rod.
Any idea why it is wobbling?
Any idea why it is wobbling?
Safety Car
Joined: Jun 2003
Posts: 4,510
Likes: 240
From: Coconut Creek FL
Originally Posted by Motorhead5673
Any idea why it is wobbling?
Generally it means that its backing itself off the crank becuase it is not keyed or pinned...or it is starting to seperate (the rubber core part) as was the case with mine...it was not pretty! I can only imagine that letting it go would really cause a lot of damage...internal and external...
Melting Slicks
Joined: Sep 2005
Posts: 2,670
Likes: 134
From: merritt island fl
C1 of Year Finalist (stock) 2019
2016 C1 of the Year Finalist
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OK, I can see how an impact wrench could get the old one off but how do you do the 140 degree tightening without holding the flywheel? Also, are there any aftermarket balancers (better than OEM) that are not underdrive, i.e. stock size?
Safety Car
Joined: Jan 2001
Posts: 3,879
Likes: 3
From: Hobart, WI
Originally Posted by dave pawlowski
OK, I can see how an impact wrench could get the old one off but how do you do the 140 degree tightening without holding the flywheel? Also, are there any aftermarket balancers (better than OEM) that are not underdrive, i.e. stock size?