pianodirt Posted October 15, 2003 Share Posted October 15, 2003 A recent new noise has popped up in my 87 wagon. There is a mid-pitch loud whirring sound coming from the front of the engine. I'm thinking it's the drivebelt fan, but not sure, maybe the alternator. It increases with the throttle and after 3000RPMs gets quite loud, almost louder than the engine itself. This always happens on a cold start and usually goes away after warming up on the freeway for a few minutes. I'm wondering if the belts might be loose, since they've never been tightened since they were replaced a couple years ago. I pressed down on one of them in the midpoint and it didn't seem to deflect more than 2/3". I'm hoping this is a common issue and someone knows what needs to be fixed/adjusted. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 15, 2003 Share Posted October 15, 2003 Run some candle wax under each belt while the engine is running, and if it goes away, then you have found the problem. You can replace the belt, and if that doesn't help, then take some emery cloth to the pully, and scuff it up a bit. GD Quote Link to comment Share on other sites More sharing options...
pianodirt Posted October 15, 2003 Author Share Posted October 15, 2003 Thanks GD, I'll try that. I take it if this is the problem, then it's merely an annoyance and not sign of a belt about to fail. The belt looks nearly new. Quote Link to comment Share on other sites More sharing options...
ByTheSea Posted October 15, 2003 Share Posted October 15, 2003 You might want to take a look at the water pump and idler pulley as possible noise sources. If the bearings are gone in the idler pully it won't effect belt tension but it will surely make lots of sound. Also the water pump bearing can fail and allow the impeller inside to touch the housing as it spins. This is usually a grating squeal. Quote Link to comment Share on other sites More sharing options...
EmmCeeBee Posted October 16, 2003 Share Posted October 16, 2003 If it's the belts themselves (not the pulleys), then I'd expect the noise to have a frequency to it -- there's always one point on the rubber belt that rubs or squeaks more than the rest. The belts have their own cadence, separate from anything else on the car. Find the lettering on the belts (or paint a white spot on 'em) and stare at it while the engine is running.... That's how I nail the belt noise every time. General's idea works. Or they have spray cans of "Belt Dressing" at auto part stores that fix 'em up good. On the subject of belts, the timing belts can make a whirring noise, also at their own cadence. From your symptoms (goes away when the engine warms up), it's probably not that. But if it's not the drive belts or pulleys, I'd consider that. That's more than an annoyance. The timing belts might need adjustment -- or replacing at 55k miles. On my other car (not a sub), the timing belt was adjusted too tight, and it sounded like a trapped butterfly. -- Mark Quote Link to comment Share on other sites More sharing options...
88rxsedan Posted October 16, 2003 Share Posted October 16, 2003 i think the noise he is talking about would be the clutch fan... when its cold the thermo clutch "grabs" more and then loosens up as it warms, then - if it gets hot enough, "grabs" again to cool the motor... my car does it too.. and its loud as hell when the motor gets warm enough Quote Link to comment Share on other sites More sharing options...
pianodirt Posted October 16, 2003 Author Share Posted October 16, 2003 Originally posted by 88rxsedan i think the noise he is talking about would be the clutch fan... when its cold the thermo clutch "grabs" more and then loosens up as it warms, then - if it gets hot enough, "grabs" again to cool the motor... my car does it too.. and its loud as hell when the motor gets warm enough Yes, what 88rx says is what happens to my car. I paid even closer attention to it today and, yes the sound does come back after the engine has been running (hotter) for quite a while. So the sound comes when it's cold, disappears when warmed a few minutes and comes back later. I've still to try the wax thing, been working all day. Quote Link to comment Share on other sites More sharing options...
88rxsedan Posted October 16, 2003 Share Posted October 16, 2003 Originally posted by pianodirt Yes, what 88rx says is what happens to my car. I paid even closer attention to it today and, yes the sound does come back after the engine has been running (hotter) for quite a while. So the sound comes when it's cold, disappears when warmed a few minutes and comes back later. I've still to try the wax thing, been working all day. its just the clutch fan - if it goes out - it will either stick on and whir all the time, or just slip, and the motor COULD get hot if you stop in traffic... just remember, if it sticks on all the time, like - ALL the time it could give you poorer fuel economy, and if your fans out of balance, it could cause premature water pump failure.. if it was belts, you would hear a sqeek or squeal, and if the fan clutch is stuck, that also could make the belts squeal because its not designed to be "direct drive" like that.. bean Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 16, 2003 Share Posted October 16, 2003 There is something else it could be - your distributor shaft bushing. Mine made an awful racket very similar to what you described when the bushing was out..... probably not, but when it makes that noise, put your hand on the disty to see if any vibration is comming from there. The noise will come and go - but mostly mine did it when it was cold, and then sometimes when it was warm. Just like what you describe. GD Quote Link to comment Share on other sites More sharing options...
pianodirt Posted October 16, 2003 Author Share Posted October 16, 2003 Uhhh...okay, another rookie question here... Am i fine to just touch the disty body? If I accidentally touch the coil or plug wires, will i get a big jolt, seeing how I got that Accel coil on there now, all the more reason not to get a shock! Thanks. Quote Link to comment Share on other sites More sharing options...
88rxsedan Posted October 17, 2003 Share Posted October 17, 2003 Originally posted by pianodirt Uhhh...okay, another rookie question here... Am i fine to just touch the disty body? If I accidentally touch the coil or plug wires, will i get a big jolt, seeing how I got that Accel coil on there now, all the more reason not to get a shock! Thanks. dont "ground" yourself to the car and you cant get shocked... but if you do get zapped, time for some new wires... bean Quote Link to comment Share on other sites More sharing options...
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