Engine Shake, I found the problem, (Maybe??)
Thread Starter
Racer
Joined: Apr 2001
Posts: 452
Likes: 0
From: Tulsa Ok, Racing the wind
Engine Shake, I found the problem, (Maybe??)
Well I finally got my head stuck down far enough to look at the Harmonic balancer on my LT1. Some of the rubber is sticking out of the inner and outer ring. About a quarter of the rubber is sliding out.
The problem is an engine shimmy around 1000 rpm's while in park. The Shimmy will stay that way if the engine is cold or warmed up. I also feel a vibration while WOT.
I have not removed the balancer yet (I'm going too, reguardless) But have any of you who have already replaced the balancer felt this seat of the pants shake??? Did the replacement of the balancer fix the problem???
I had a friend say "No Way that can't be the problem" I also noticed the belt tensioner around 1000 rpm's jumps around quite a bit.
How much is a replacement, Don't want to get to fancy, just get her running smooth.
Stay Stock, or reasonable priced performance options? :confused: :)
The problem is an engine shimmy around 1000 rpm's while in park. The Shimmy will stay that way if the engine is cold or warmed up. I also feel a vibration while WOT.
I have not removed the balancer yet (I'm going too, reguardless) But have any of you who have already replaced the balancer felt this seat of the pants shake??? Did the replacement of the balancer fix the problem???
I had a friend say "No Way that can't be the problem" I also noticed the belt tensioner around 1000 rpm's jumps around quite a bit.
How much is a replacement, Don't want to get to fancy, just get her running smooth.
Stay Stock, or reasonable priced performance options? :confused: :)
Team Owner
Joined: Sep 2001
Posts: 62,139
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From: Athens AL
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Re: Engine Shake, I found the problem, (BBA)
Every time id heard of it, fixing the balancer fixed the problem.
Thread Starter
Racer
Joined: Apr 2001
Posts: 452
Likes: 0
From: Tulsa Ok, Racing the wind
Re: Engine Shake, I found the problem, (BBA)
Why couldn't that be the problem?
I have gave the engine a full tune up, wires (Taylor 8mm), plugs NGK TR55's, had the fuel injectors cleaned (they really needed it, 30% flow on 3 of them) Sea foamed the intake and all the other stuff. The engine really runs strong now, but the shimmy is still there.
I thought the balancer sounded like the culpret. :yesnod:
Race Director
Joined: Nov 2000
Posts: 10,340
Likes: 664
From: Beverly Hills (Pine Ridge) Florida
Re: Engine Shake, I found the problem, (BigTodd)
Yes, the balancer can be at fault per your description. However, that belt dancing around is also not good. Either a bad belt (check the grooves for tear out, etc.) or something is not "round" anymore (check your pulleys).
Normally, a defective balancer vibration gets worse with RPM, whereas a defective belt "could" vibrate at one particular RPM, and then be OK elsewhere. If you see maximum belt dance at the same RPM where you feel the vibration, then that is your clue.
Normally, a defective balancer vibration gets worse with RPM, whereas a defective belt "could" vibrate at one particular RPM, and then be OK elsewhere. If you see maximum belt dance at the same RPM where you feel the vibration, then that is your clue.
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Engine Shake, I found the problem, (Plasticman)
Sounds like the balancer is the problem to me. There's a reason it's called a balancer... it helps out with balancing the engine (not a whole lot on the LT1's though). If it's out of balance, so will the engine.
Race Director
Joined: Oct 2000
Posts: 16,477
Likes: 1
From: Enter Post Count Here
Re: Engine Shake, I found the problem, (BigTodd)
My OEM cheby torsion damper was $73 for my L98, I'd guess for your internally balanced LT1, you're looking at about $120.
The tensionor bouncing is kind of weird though, I would look at that after you replace the damper, I think it will probably fix that too. If not, check the bearings in the pully.
Good luck. :)
The tensionor bouncing is kind of weird though, I would look at that after you replace the damper, I think it will probably fix that too. If not, check the bearings in the pully.
Good luck. :)
Burning Brakes
Joined: Nov 1999
Posts: 859
Likes: 17
From: Houston TX
Re: Engine Shake, I found the problem, (NoWorries)
The tensioner is just a spring. It can stretch and fatigue. If its bouncing around a lot, go ahead and replace it when you replace the balancer.
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Safety Car
Joined: Dec 2000
Posts: 3,767
Likes: 5
From: Jacksonville Fl
Re: Engine Shake, I found the problem, (BigTodd)
Well...no matter what he said, you have a bad/defective balancer...you have to change it anyway. :smash:
Then you can come back to tell us if it fixed the vibration.v :cheers:
Then you can come back to tell us if it fixed the vibration.v :cheers:
Intermediate
Joined: Jun 2000
Posts: 28
Likes: 0
From: monaca pa
Re: Engine Shake, I found the problem, (BigTodd)
Replace the balancer. If you have never had the balancer pulley off there will be a good chance that it is rusted on. Best way to remove is to jack the front end or place on ramps, remove the three bolts, get under the car and strike the balancer pulley with a brass drift using a 4-5 pound hammer. Strike toward the center of the pulley. Do not be afraid to hit the balancer hard. It will take several hits to move it off of the hub. Once removed replace your tensioner also.
Thread Starter
Racer
Joined: Apr 2001
Posts: 452
Likes: 0
From: Tulsa Ok, Racing the wind
Re: Engine Shake, I found the problem, (steve bavaro)
Well, the balancer is changed, and the shake still is there :mad
I did find out something though, The reason my tentioner was bouncing around was that there was several pieces of the old serpentene belt wedged into the old harmonic balancers grooves. Took a screwdriver and knocked them out. Man they were stuck in there good.
Anyway the extra material was causing the belt and tentioner to jump around, so if you see the same thing happening, pop you belt off, get a good light and clean out the balancers grooves. My new balancer and belt runs very smooth now. :rolleyes: Torque Converter may be next... :confused:
I did find out something though, The reason my tentioner was bouncing around was that there was several pieces of the old serpentene belt wedged into the old harmonic balancers grooves. Took a screwdriver and knocked them out. Man they were stuck in there good.
Anyway the extra material was causing the belt and tentioner to jump around, so if you see the same thing happening, pop you belt off, get a good light and clean out the balancers grooves. My new balancer and belt runs very smooth now. :rolleyes: Torque Converter may be next... :confused:
