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Harmonic Balencer? (3.8N/A)

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Old 03-02-2011, 11:25 PM
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Default Harmonic Balencer? (3.8N/A)

damn car, 97 LSS - 215k miles, presumed to be original balencer...

runs great - still feels "powerful" -

but...



i've noticed a vibration from my engine, since i got it - at idle, primarily, you can feel it if you rest your hand on the open door, or hold a hand on the dashboard... recently i've found myself noticing it a little more here and there, like a 'hop' that could be engine mounts or something... but

tonite (i was driving with head phones on... don't ask.) i was at a light, and the song ended - heard what sounded like a rod knock - in gear - at a stop - with my foot on the brake...

so i released it into neutral, and the noise prettty much went away.

back in gear - instant knocking sound again... seems to be matched to the dip in rpm'*.... from straining the engine..

my lights have been dimming a little lately, if i, roll all 4 windows up at once lets say, or jack my heat on full blast from off - car never used to do that and the alternator'* new.


it makes this, metal knocking noise, does it Especially in reverse/forward, hardly at all in neutral, but i do hear something'* off when i rev the engine in neutral... it sounds like, something extra is happening - like a blender almost - at about 3500rmp'*..


also, i've been experiencing a vibration that comes and goes, at speed/on the highway..tires balenced - allignment'* good - could this be my gremlin?



*also- i've been hearing a 'screeching' noise, if i - jam the pedal and drop 2 gears lets say... abrupt changes in acceleration.. or accelerate very quickly, then let off... it'* quick, but it happens at the same time as the tranny shifts.. it'* consistant, and only does it during more drastic RPM changes (WOT-redline, let off... or putting along, and mash it) my tranny fluid'* good, filter'* new, it behaves prettty damn well overall..










Finally, I read up a little online, and with my bare hands - and a moderate amount of muscle, I can pull the serpentine belt a full inch or so back and fourth..
if i rev the engine from under the hood, while watching the balencer, it doesn't "wobble" ridiculously... but the outer-most, center, of the bearing (faces the pass. engine mount) does some dancing around with RPM fluctuation,


harmonic balencer?


Thanks,
Joe
Old 03-02-2011, 11:34 PM
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sounds like it could be the harmonic balancer .If you have a timing light you can watch the balancer move . start with the simple exterior parts
Old 03-02-2011, 11:35 PM
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Either Harmonic balancer or loose torque convertor bolts..
Old 03-02-2011, 11:41 PM
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unfortunately, it could be either - the tranny was replaced 1 year/35000miles ago,
the crank sensor was replaced shortly after,

at any point - human error could have occured.

it will be at the shop/on a lift tomorrow.


Should a harmonic balencer turn perfectly smooth at all times, or is it designed to visibly move around at all (this one doesn't do anything scary to look at, but the center portion does have some in/out to it i can see with my flashlight
Old 03-02-2011, 11:45 PM
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if no thread locker was used on the bolts it could be possible....im not sure about the HB ive never watched one in action
Old 03-02-2011, 11:51 PM
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p.*. i was just out screwing around with it again, and i moved the belt like 8-9inches with bare hands...

also, i can see metal shavings on my belt.../around the harmonic balencer (similar to what my a/c compressor did when it went bad, except it'* been cleaned 1000x since then)

the outside of the balencer, outermost passenger'* side, wobbles around pretty good while it'* on.
Old 03-02-2011, 11:57 PM
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The rubber in the center is more than likely shot i would say pull your pass side wheel and splash guard investigate and replce..Sounds like youve found the issue
Old 03-03-2011, 12:06 AM
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excellent.

i hope this is, what it is - new balencer, new belt, new tensioner if needed -

god damnit.

buttt i love my car.

thanks,

any other thoughts let me know
Old 03-03-2011, 03:57 PM
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just keep us updated would be cool
Old 03-03-2011, 08:22 PM
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Loose torque converter bolts.



re-torqued via access panel under the car, and it drives real nice now.




we did check, and re-check, the harmonic balencer - and it is getting old, slight bit of play in/out with the pry-bar, and there is a noticable amount of vibration coming from the engine - we're going to replace that as well, but not til next week or some convenient time.


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