Harmonic Balance Pulley Question
Thread Starter
Instructor
Joined: Jun 2003
Posts: 187
Likes: 0
From: Orange Park Fl
Harmonic Balance Pulley Question
98 coupe. Coming home the AC stopped working. Found that the belt has thrown so I tried to reinstall it. Come to fine the harmonic balance is sitting forward of the engine and the pulley is not aligned with the water pump, AC, Idlers etc. There is no wobble and the bolt appears tight. Looks like the pulley belt flange just pulled forward on the part that connects to the camshaft. Is this a compression fit with some kind of rubber bushing? Kind of reminds me of throwing a stainless steel prop on a boat.
Any insight would help. Already read about what it will take to replace it. I have to go in to replace a leaky ac compressor so that and the water pump are already going. Looks like I have to move the steering rack to get this done.
Thanks in advance !
Any insight would help. Already read about what it will take to replace it. I have to go in to replace a leaky ac compressor so that and the water pump are already going. Looks like I have to move the steering rack to get this done.
Thanks in advance !
Melting Slicks
Joined: Feb 2007
Posts: 3,194
Likes: 10
From: New Smyrna Beach Florida
Sounds like a good time to install a cam and an underdrive pully. Hopefully there is no colateral damage associated with the crank pully.
You'll know whats going on when the pully is removed. Good luck!!
You'll know whats going on when the pully is removed. Good luck!!
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
The inner hub of the harmonic damper is attached to the pulley with an elastomer compound. It sounds like that has failed. You need to replace the part. You need some special tools and a new harmonic damper and bolt to do this.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 187
Likes: 0
From: Orange Park Fl
Is this something that is common? If that compound has failed, when I use the balance puller will it pull the belt ring and leave the hub of the harmonic balance on the camshaft? Is there a replacement part I can get that is still stock in dimensions but better built.
Thanks
Thanks
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Is this something that is common? If that compound has failed, when I use the balance puller will it pull the belt ring and leave the hub of the harmonic balance on the camshaft? Is there a replacement part I can get that is still stock in dimensions but better built.
Thanks
Thanks
IMHO the best replacement for the stock balancer is made by ATI and while you have it off I would pin the crank also.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Is this something that is common? If that compound has failed, when I use the balance puller will it pull the belt ring and leave the hub of the harmonic balance on the camshaft? Is there a replacement part I can get that is still stock in dimensions but better built.
Thanks
Thanks
Last edited by vettenuts; Sep 29, 2008 at 07:18 PM.
Melting Slicks
Joined: Aug 1999
Posts: 3,452
Likes: 3
From: Spring, TX
A three arm puller is used to remove the pulley. It doesn't contact the outer ring. You position the three arms into the openings of the innder hub structure that is on the crank.
Yes this is a common problem on the LS motors. Do not use a stock replacement pulley. You can purchase several different aftermarket parts either underdriven or stock diameter.
You were lucky that the outer inertia ring slid forward. Mine failed and slid back and took out the front engine cover, oil pan, oil pump, and timing chain. Very expensive fix even with me doing all the work. Excelent time to do a cam swap I did!
Yes this is a common problem on the LS motors. Do not use a stock replacement pulley. You can purchase several different aftermarket parts either underdriven or stock diameter.
You were lucky that the outer inertia ring slid forward. Mine failed and slid back and took out the front engine cover, oil pan, oil pump, and timing chain. Very expensive fix even with me doing all the work. Excelent time to do a cam swap I did!
Instructor
Joined: Jun 2006
Posts: 107
Likes: 0
From: Siloam Springs AR
I am in the same boat as you. The pulley is about 1 rib forward out of alignment. It likes to shear the inside rib of the belt as it tries to align itself backwards if I do any agressive driving. I looked into labor to have it done - about 370 dollars. I am still not sure if want to try it myself. I would like to work on the car but it is a little intimidating as this would be the first thing I will have done. I might be able to talk the wife into a ported oil pump if I do it myself. Keep us in the loop on what you decide. I've been watching these treads hoping someone would be working on the same thing soon.
Last edited by The Void; Sep 29, 2008 at 06:37 PM. Reason: grammatically challenged
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Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Melting Slicks
Joined: May 2006
Posts: 2,303
Likes: 40
From: Edmonton Alberta
Either way, there is a bit of work to make it right again. It would be a good time for modifications.
Thread Starter
Instructor
Joined: Jun 2003
Posts: 187
Likes: 0
From: Orange Park Fl
Thanks folks,
I'm going to do the job myself since I have to replace the leaking AC compressor. Been saving up the "to do" list since the car has 80K on it. Conslidating all the work while I have the car in the air on jack stands.
List includes:
AC Compressor, accumulator, orifice tube
Water pump,gaskets upper lower hoses (has to come off to get to AC)
Harmonic balance
Remove and clean Throttle body istall new gasket
End Links, Stabilizer bushings, tie rod ends
Shocks all around
Plugs and Wires
Brakes, rotors and paint the calipers
All fluids changed
Have wheels ground force balanced
Should keep me in the garage on weekends for a couple of weeks. Don't need the car as a daily driver so no pressure. Will let you know how it goes and if I need help. If there is any other maintenance I should consider let me know. Not really into modding the car..like the stock setup. The Void can PM me if you have questions as I work through this.
I'm going to do the job myself since I have to replace the leaking AC compressor. Been saving up the "to do" list since the car has 80K on it. Conslidating all the work while I have the car in the air on jack stands.
List includes:
AC Compressor, accumulator, orifice tube
Water pump,gaskets upper lower hoses (has to come off to get to AC)
Harmonic balance
Remove and clean Throttle body istall new gasket
End Links, Stabilizer bushings, tie rod ends
Shocks all around
Plugs and Wires
Brakes, rotors and paint the calipers
All fluids changed
Have wheels ground force balanced
Should keep me in the garage on weekends for a couple of weeks. Don't need the car as a daily driver so no pressure. Will let you know how it goes and if I need help. If there is any other maintenance I should consider let me know. Not really into modding the car..like the stock setup. The Void can PM me if you have questions as I work through this.
Melting Slicks
Joined: Aug 2000
Posts: 2,618
Likes: 5
From: Overland Park KS
Buy an LS3 water pump. It weighs less and the design has less rotating mass. The old bell pulley is replaced with a flat design. I use one on my 418ci build and it's working great. Search for "LS2 LS3 waterpump" on fleabay for a seller in Missouri and offer him $15 less (best offer option).
May want to update the power steering pulley from solid/plastic older model to open wagonwheel/metal design of the LS3. It makes service a little easier with the ability to loosen the bolts behind the pulley.
Remember you must also use a new crank bolt, you can not reuse the old one. I actually use the old bolt to get the pulley started and tighten it a bit and then remove it and install the new crank bolt and tighten it to the proper torque spec.
May want to update the power steering pulley from solid/plastic older model to open wagonwheel/metal design of the LS3. It makes service a little easier with the ability to loosen the bolts behind the pulley.
Remember you must also use a new crank bolt, you can not reuse the old one. I actually use the old bolt to get the pulley started and tighten it a bit and then remove it and install the new crank bolt and tighten it to the proper torque spec.
Melting Slicks
Joined: Aug 1999
Posts: 3,452
Likes: 3
From: Spring, TX
Absolutely do not do that. Go over to LS1tech.com and look up pulley installation tool. Either make one or buy one from one of the members on there. Do not use the old bolt to force the new pulley on. The pulley is literaly stretched over the crank snout. When it first hits the end of the crank there is a hell of a lot of tension on there and the bolt is in only a few threads. You are asking to strip them out of the crank snout and then you are completely screwed!
Instructor
Joined: Nov 2007
Posts: 129
Likes: 1
From: Houston, Texas
I went through this exercise nearly a year ago and highly recommend a tool like the one Vettenuts has posted. I even used that tool coupled with a PVC pipe coupling to pull the new seal into position.
Burning Brakes
Joined: Aug 2006
Posts: 1,217
Likes: 5
From: Stark County Ohio
GREAT TIP. I hadn't thought of this method to "press" the seal into place. I've used a pipe with a cap on its end to "tap" the seal into place.