Penglii Posted December 30, 2009 Report Share Posted December 30, 2009 Sometimes I get a strange noise coming from some part of the serpentine belt system. It is intermittent, but consistent... maybe occurs a third of the time (very rough estimate). When it occurs it will continue until the car has been off for a few hours at least. I have not been able to determine any specific conditions unique to the presence of the noise. Anyway... I'm not entirely sure how to describe it. The best I can come up with is that it sounds like a metal chain jangling against a piece of pipe. That description probably sucks though. It is definitely NOT a squealing or screeching noise... and does not appear to coincide with any belt slippage. The noise also does NOT coincide with any discernible performance issues... at present it is just an annoying noise. It sounds to me as like the alternator bearings are failing... but I don't currently have a stethoscope so I can only guess. Any ideas? Quote Link to comment Share on other sites More sharing options...
GP1138 Posted December 30, 2009 Report Share Posted December 30, 2009 Either alternator bearings or A/C compressor noise, the latter of which tends to be common on 3.4L DOHC cars of that era, and probably happens to plenty of 3100 cars like yours. Switch on the A/C and see if it goes away. Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted December 30, 2009 Report Share Posted December 30, 2009 My A/C compressor went bad, and it was more of a squealing noise.I just had mine taken out. I have a convertible so no need for A/C. Quote Link to comment Share on other sites More sharing options...
Penglii Posted December 30, 2009 Author Report Share Posted December 30, 2009 If it is the alternator bearings, why would it be an intermittent noise? Wouldn't failing bearings be noisy all the time? That said, when I got the car the battery was utter crap... which probably overworked the alt, so there is reason to suspect it. Regarding the A/C Compressor... thanks for the suggestion. I will check that out if the opportunity arises during my lunch break this afternoon. Quote Link to comment Share on other sites More sharing options...
MonteCarloChick Posted December 30, 2009 Report Share Posted December 30, 2009 idler pulley tensioner. mine jangles too Quote Link to comment Share on other sites More sharing options...
3pt1lumina Posted December 31, 2009 Report Share Posted December 31, 2009 I'm chasing a rattling noise now myself... The tensioner was bad...it had way too much play in it so I replaced it. Didn't change anything. Started looking further and the power steering pump would turn maybe 1/4 of a turn without the belt on it if you spun it by hand. Replaced that and the pulley (which had cracks in it)... still have the noise. If I turn the A/C on it doesn't seem to change... alternator is 2 years old and doesn't seem to spin with any resistance or noise. If take a screw driver and put it on each part, and I hear the most noise coming from the water pump. I can't reach down to the A/C compressor safely to check it in the driveway. So I'm not sure what to suggest to you, just trying to show you how I am unsuccessful in diagnosing my car. Hopefully that was some help. Quote Link to comment Share on other sites More sharing options...
chevyguy8893 Posted December 31, 2009 Report Share Posted December 31, 2009 I agree with the A/C compressor possible causing the noise. The alternator generally squeaks or chirps, at least from the ones I have come across. Check for fine metal shavings on the A/C compressor, it may indicate the beginning of a problem. Quote Link to comment Share on other sites More sharing options...
GP1138 Posted December 31, 2009 Report Share Posted December 31, 2009 My 3.4L would do it intermittently too. Quote Link to comment Share on other sites More sharing options...
94 olds vert Posted December 31, 2009 Report Share Posted December 31, 2009 My 3.4L would do it intermittently too. x2 Yup, once I saw metal shaving I just gave up and had it pulled out. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted December 31, 2009 Report Share Posted December 31, 2009 look behind the tensioner on the timing cover. if you see any scoring on the cover, CHANGE THE TENSIONER! Quote Link to comment Share on other sites More sharing options...
Penglii Posted December 31, 2009 Author Report Share Posted December 31, 2009 look behind the tensioner on the timing cover. if you see any scoring on the cover, CHANGE THE TENSIONER! I have a 3100, so there is no timing cover. Current winning idea is the A/C Compressor. Although there was no jangling at all today... I guess that is murphy's law in reverse. I suppose I'll get to test that theory tomorrow. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted December 31, 2009 Report Share Posted December 31, 2009 the big slab of aluminum behind all the pulleys is refered to as a timing cover.... Quote Link to comment Share on other sites More sharing options...
Penglii Posted December 31, 2009 Author Report Share Posted December 31, 2009 the big slab of aluminum behind all the pulleys is refered to as a timing cover.... Ahhh... that makes sense. Sorry, for a minute all I could remember was the timing cover on my old jalopy (`99 Dodge Neon 2.0L dohc coupe, may it rust in pieces)... I will definately check it for scoring. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted December 31, 2009 Report Share Posted December 31, 2009 the big slab of aluminum behind all the pulleys is refered to as a timing cover.... Ahhh... that makes sense. Sorry, for a minute all I could remember was the timing cover on my old jalopy (`99 Dodge Neon 2.0L dohc coupe, may it rust in pieces)... I will definately check it for scoring. FAIL! take a 3/8 rather and stick it in the tensioner. pull up and see if it wiggles side to side(I just found one that was bad, which did not move while tensioned, but did the rest of the time....). remove belt and hand turn ALL pulleys. notice anything that makes noise, it hard, or toooo easy to turn? if you want a j/y tensioner, get one from an older 3.1 (like 92 and earlier) as the earlier design is better and they interswap between 3100 and 3.1s. Quote Link to comment Share on other sites More sharing options...
Penglii Posted December 31, 2009 Author Report Share Posted December 31, 2009 FAIL! EPIC FAIL! It's just proof that my dreams are still haunted by that screaming metal deathtrap. Whoever at Chrysler thought that a solid aluminum interference engine, with a "permanant" timing belt, and a crappy head gasket was a good idea really needs to rethink their design decisions. The maybe 1"x1" timing belt cover "porthole" was worse than useless for determining the wear status of the belt. 135,000 miles on the original factory timing belt was a scary circumstance. Lucky for me the engine did not self destruct too badly during the 65,000 I put on that sardine-can. Quote Link to comment Share on other sites More sharing options...
Night Fury Posted December 31, 2009 Report Share Posted December 31, 2009 My monte makes so many jangling noises it should be called the freaking clown car Quote Link to comment Share on other sites More sharing options...
frank b Posted January 4, 2010 Report Share Posted January 4, 2010 does it sound like an old alarm clock? Mine did that when the AC clutch, on the compressor, was bad. I replaced the whole compressor. On mine, I could see it rattling. Remember that the clutch spins free when the ac is not on. Quote Link to comment Share on other sites More sharing options...
Penglii Posted January 4, 2010 Author Report Share Posted January 4, 2010 It does sound somewhat like an old alarm clock, the kind with the 2 bells & hammer for the alarm. It is definitely seeming like the Compressor Clutch needs an adjustment. I've been paying attention the past few days, and here is the scoop: When the engine is cold (presumably still in open loop), it will sometimes make noise and othertimes not... no discernible pattern. When the engine has warmed up (presumably now in closed loop), the noise ceases if the A/C or Defrost is already on... if the A/C is not already on, the noise will cease shortly after turning it on. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted January 4, 2010 Report Share Posted January 4, 2010 how about when it's cold, with the A/C off and driving? does it go away? if so, it sounds kind of like worn timing chain/sprocket... switching on the a/c-defrost loads the motor and takes slack out of the chain... Quote Link to comment Share on other sites More sharing options...
Penglii Posted January 4, 2010 Author Report Share Posted January 4, 2010 how about when it's cold, with the A/C off and driving? does it go away? if so, it sounds kind of like worn timing chain/sprocket... switching on the a/c-defrost loads the motor and takes slack out of the chain... No. With the engine cold (or warm for that matter), the A/C-defrost off, and driving, the noise persists. Edit: I should emphasize once again that the noise is not a constant. When it is present, sometimes it is louder and sometimes it is softer. It also seems that if the A/C is run for a while, the next time the noise occurs it is not as loud... although because there are also occasions where the A/C-defrost is off and the noise is absent that might be an illusion. The more I ponder it all, the more likely it seems that it would be a Compressor Clutch in need of a slight adjustment. I am assuming that because it is variable and not "full volume all the time", that if I get the adjustment made soon I might not suffer any significant Compressor damage. Too bad it is so cold out. Quote Link to comment Share on other sites More sharing options...
frank b Posted January 5, 2010 Report Share Posted January 5, 2010 It does sound somewhat like an old alarm clock, the kind with the 2 bells & hammer for the alarm. It is definitely seeming like the Compressor Clutch needs an adjustment. I've been paying attention the past few days, and here is the scoop: When the engine is cold (presumably still in open loop), it will sometimes make noise and othertimes not... no discernible pattern. When the engine has warmed up (presumably now in closed loop), the noise ceases if the A/C or Defrost is already on... if the A/C is not already on, the noise will cease shortly after turning it on. If it stops when the ac/defroster is on, it sure sounds like it's the ac clutch.... Can you see it wiggling while the engine is running? Quote Link to comment Share on other sites More sharing options...
Penglii Posted January 5, 2010 Author Report Share Posted January 5, 2010 If it stops when the ac/defroster is on, it sure sounds like it's the ac clutch.... Can you see it wiggling while the engine is running? I am not sure yet... it has been too cold and dark after work for me to watch the pulleys spin. I assume that with the a/c-defroster OFF and the engine ON that the compressor pulley should be spinning freely and not wobbling at all? Quote Link to comment Share on other sites More sharing options...
frank b Posted January 19, 2010 Report Share Posted January 19, 2010 If it stops when the ac/defroster is on, it sure sounds like it's the ac clutch.... Can you see it wiggling while the engine is running? I am not sure yet... it has been too cold and dark after work for me to watch the pulleys spin. I assume that with the a/c-defroster OFF and the engine ON that the compressor pulley should be spinning freely and not wobbling at all? When the ac is off, the clutch is released so the pulley spins free without turning the compressor. Ac on, the clutch engages to turn the compressor. When off, it should be smooth, no play, or rattling at all. If that clutch breaks, or the bearing siezes, your belt is toast! Which could mean an overheated engine, or at least a dead battery before you realize it. Quote Link to comment Share on other sites More sharing options...
96oldsmobubble Posted January 24, 2010 Report Share Posted January 24, 2010 I have a 96 Cutlass Supreme with the 3100 and went through the same deal. Jangling noise eventually was the ac compressor clutch. Kind of coincidental or related incident though because at the time when it finally went, I was couple blocks from home, turned a corner and the battery light came on and no power steering. Got under the hood, power steering pump pulley was gone and the belt was missing one rib. Talked to mechanic after I replaced power steering pump and pulley and new belt, he told me to unhook the electrical connector for the ac clutch until I could get it to him to replace the clutch. Yes, like what was said look for metal shavings around the ac compressor and try unhooking the clutch wire. After my clutch was replaced, no jangle and ac/ defrost works beautifully! Hope this helps, good luck, Tim Quote Link to comment Share on other sites More sharing options...
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