Harmonic Bal. question.
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Harmonic Bal. question.
Hi, the other day my belt snapped on the inside part of the belt, i pulled over and removed the peices of the belt that were loose so they would not slap the other parts as they went around the pulleys, tried to start it and it would run real rough for a few sec. then finally die. once home, i started to look into it, the teeth on the Back of the Harmonic Bal were bent outward (five of them) and so they were not passing thru the crank sensor, Not being able to buy a new Bal. i simply took a chisel, and a hammer, and tapped the teeth straight, or as close as i could get them, then rotated the harmonic bal. manually to make sure they went thru the sensor. When i got done, the car started fine, actually has alittle more power then it did before it stopped running, the only problem now is that there has been a noise coming from the tensioner along with it jumping around, this has been going on for a while now, ive replaced the pulley and the assym. still the noise and jumping. today i was looking at this when i got home from wk, and it looks like when the car is running that the harmonic bal, is about to fall off.. its moving around alot. when i was down fixing the teeth on the plate, the balancer did not feel loose.. so yall think i need a new Balancer? this one is only 4 months old.
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Only being 4 months old..I wouldn't assume it is bad, however it sounds like there is a circumstance that could be causing it to be bad.
Can you get a vid of it?
Can you get a vid of it?
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yea, lol i think that i know exactly what you mean, i just wanted to make sure that there was no mechanical way that the thing could fly off.
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If I'm not mistaken, the balancer on the 3800 is an isolator assembly that includes a bearing. I'd find it hard to believe it'* bad after 4 months, but it'* possible the bearing went bad.
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Originally Posted by ZeeVert
If I'm not mistaken, the balancer on the 3800 is an isolator assembly that includes a bearing. I'd find it hard to believe it'* bad after 4 months, but it'* possible the bearing went bad.
It'* an inner balanced part with one or two rings on it. 3X and/or 18X to feed the crank sensor. Then rubber to isolate and metal ring with belt grooves to drive the accessories
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I had the same problem 5 years ago and straightened my fins exactly as you did and have had no problems since. The fins shredded my crank sensor though so i did replace that.
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Originally Posted by BillBoost37
Originally Posted by ZeeVert
If I'm not mistaken, the balancer on the 3800 is an isolator assembly that includes a bearing. I'd find it hard to believe it'* bad after 4 months, but it'* possible the bearing went bad.
It'* an inner balanced part with one or two rings on it. 3X and/or 18X to feed the crank sensor. Then rubber to isolate and metal ring with belt grooves to drive the accessories
Unless it'* a weird aftermarket version, this thing does have a bearing inside it, although it'* usually the rubber that goes bad.
I'll have to see if I can find a picture of a cross section.
Anyway, those are the crank sensor rings that are getting bent.
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If memory serves, that would be a 95 L67 HB (you had to be there)
The rubber does go bad and shreds all the way around the edge. I'm interested to see this cross section....
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yes.. that sounds just about right... there is a rattling sound that i think was coming from the tensioner pulley. If what you say about the harm. bal. the sound that im hearing is the bearings, and this is causing the tensioner to jump the way it is. but yes, that is what my harmonic bal. looks like, ill get another one in a day or two, and replace it myself to save myself another 310.00. thanks guys
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The bearing on the balancer never fully rotates, it only rotates back and forth a little within the limits of the rubber or the hard stops. If the bearing is bad, I would expect the pulley portion to rattle and shake.
Some other info from my memory...
This was a very low frequency damper that served to isolate the engine harmonics from the accesory drive. Most other harmonic balancers are tuned to much higher frequencies to protect the crankshaft.
Virtually every year there was a new part number, because the counter balance weight would be changed. Probably because of changes to the crank, pistons or rods. You don't want to mix years.
The sensor rings also changed every few years as the igniiton system was improved. They were held in with tamper proof torx screws, because the stampings and their location to the crank keyway was so tightly toleranced. (So I get a little chuckle when people straighten them out with a hammer and chisel)
Some other info from my memory...
This was a very low frequency damper that served to isolate the engine harmonics from the accesory drive. Most other harmonic balancers are tuned to much higher frequencies to protect the crankshaft.
Virtually every year there was a new part number, because the counter balance weight would be changed. Probably because of changes to the crank, pistons or rods. You don't want to mix years.
The sensor rings also changed every few years as the igniiton system was improved. They were held in with tamper proof torx screws, because the stampings and their location to the crank keyway was so tightly toleranced. (So I get a little chuckle when people straighten them out with a hammer and chisel)