Bearing noise from front of engine - how to diagnose? (1 Viewer)

[fooldall1]

All:

I'm hoping that all you guys or gals might share some knowledge on this topic..


I have a 2k LC, 215k miles. Engine runs smoothly, but has what I suspect to be a bearing noise coming from one of the pulleys in the front. So my question basically is, how does one locate the correct bearing/ pulley to replace? It's not a whine (like alternator bearing) and the belt is relatively new.

Noise sounds like a bearing "clacking", but I'm only a novice. I can record the sound and post here if that's allowed.

Looked in the FAQ, but didn't see any specific steps to diagnose.

Any diagnostic tips?

Thanks in advance!

 

[flintknapper]

Take a 14mm wrench, release the pressure on the tensioner for the serpentine drive belt. Remove drive belt. Turn (by hand) each and every pulley and feel and listen for any that seem rough.

Recording the sound (if not a whining sound) really won't do us any good.

 

[04UZJ100]

If it's from the lower passenger side area on the front, it could be the alternator going out. Mine whined before it died.

 

[abuck99]

Adding to Flintknapper's instructions, also check for play- worn bearings will sometimes spin freely but they have a slight wobble or play when you push or pull on them.

Where possible listen at all pulleys using a stethoscope or using a long extension.

If it's either tensioner or idler pulley bearings, these can be removed pressed out and new ones pressed in $10 vs $60

 

[BlueWeim]

id guess tensioner or idler. you can check them listening with a real long extension if a stethoscope isnt accessible.

you might also check the fan bracket if its a "clacking" noise rather than the whining/whirring of bad bearings.

 

[PADDO]

All good advice re trying to isolate which, or all of, the bearing(s) that are dry, tired and on their way out. If you suspect idler or tensioner pulleys [very reasonable assumption] and are happy to go the Gates replacement path the idler is about $40 and the tensioner pulley is only about $20. Using all the standard insitu bearing diagnostics recently I thought my idler was the noisy culprit but I grabbed a replacement tensioner pulley too. On removing and replacing both pulleys turned out my tensioner pulley bearing was the worst. OP if you've got 215k on a 17 year old vehicle you might just change idler and tensioner pulley out together.

 

[fooldall1]

Good advice. I will look in the FAQ for instructions on replacing both idler and tensioner pulleys. Right off, does anyone know if those jobs require a removal of the fan clutch/shroud? I can't see any reason why NOT to invest the 60 bucks in new pulleys and just invest the time and gain some knowledge. Thanks Guys, for all the responses.

 

[fooldall1]

I will post this in a separate thread if you guys think it's worth it- but, I also *think* I need a new steering rack. How does one know if one just needs bearings for the rack vs. all new rack? Could worn tie rod ends give a "heavy" turn feel?

 

[fng36]

If the squeal is constant, TURN OFF the engine, and touch the pulleys. The warmest one is usually the bad one

 

[fooldall1]

Blueweim, you're right..it's more of a whirring noise.

 

[gatormark91]

Jason - was going to send you this thread until I realize it was YOUR THREAD.

Follow above advice about pulling belt and checking pulleys, first. That is easiest way to tell if it's a pulley. If that doesn't tell you anything, need to dig more.

PS pump noise should change tone when steering is turned. Alt bearings are another culprit, but that is harder to diagnose. That you should be able to hear better from underneath with skid plate off.

We'll figure it out, was hard to tell looking at it at night in your driveway!

 

[fooldall1]

Thanks, Everyone! I will post an update when I know what the solution is.

 

[bucfl]

Just replaced the tensioner pulley wheel a litttle while ago and you will need to remove fan for better accessibility and clearance.

You can also try spraying wd40 and if the sound clears and returns after a few minutes you found the problem.

I went through water and I'm hearing grinding. Im also finding it I need to try at least three times to start it in the morning. But fine throughout the day.

It hasn't happened in a few days so I'm thinking it's the alt. Bought one last Year so it's getting replaced in a few weeks.

 

[bmw635]

Get a long steel bar, socket extension and put 1 end on each of the moving part and the other end to your ear - the noise will amplified itself on bad part, which could be bearing from water pump clacking noise.

 

[fooldall1]

Just replaced the tensioner pulley wheel a litttle while ago and you will need to remove fan for better accessibility and clearance.

You can also try spraying wd40 and if the sound clears and returns after a few minutes you found the problem.

I went through water and I'm hearing grinding. Im also finding it I need to try at least three times to start it in the morning. But fine throughout the day.

It hasn't happened in a few days so I'm thinking it's the alt. Bought one last Year so it's getting replaced in a few weeks.

so, I'd just spray wd-40 in the center of the pulley and see what happens? What if some gets on the belt? Doesn't that stuff foul the belt?

 

[seanz0rz]

I think my serpentine idler (top, driver's side of engine) is going. Similar sound. I'm curious to see what is your culprit. I don't have time to dive into mine until probably next month.

 

[bucfl]

so, I'd just spray wd-40 in the center of the pulley and see what happens? What if some gets on the belt? Doesn't that stuff foul the belt?

It will be okay.

 

[duggy]

Get a long steel bar, socket extension and put 1 end on each of the moving part and the other end to your ear - the noise will amplified itself on bad part, which could be bearing from water pump clacking noise.

Great way to jam an extension into your ear if it slips on the belt.

I agree with taking off the belt and spinning each part to see which one doesnt spin freely/has play/has worn bearings.

 

[fooldall1]

Thanks for the great advice, All.

I will drop the belt and check out each pulley. As I was watching the general area of the noise, I saw the Tensioner Pulley "wiggling", mind you- not the pulley itself (as far as I could tell), but the whole assembly on it's spring. I will post a vid here so everyone can weigh in. Could be normal as far as I know..

 

[flintknapper]

Thanks for the great advice, All.

I will drop the belt and check out each pulley. As I was watching the general area of the noise, I saw the Tensioner Pulley "wiggling", mind you- not the pulley itself (as far as I could tell), but the whole assembly on it's spring. I will post a vid here so everyone can weigh in. Could be normal as far as I know..

IF the spring is weak...some amount of movement is to be expected. There are a few tell-tale signs that can help narrow things down. First and foremost would be to positively I.D. the noise as coming from the front of the engine. Once you've done that....then categorize the noise (whining, whiring, grinding).

IF a 'whining' sound (at front of engine) there are really only two possibilities. Either the power steering pump or your alternator. With engine running, move the steering wheel back and forth and IF the sound increases or changes pitch, your PS pump is suspect. If it does NOT change then look to your alternator. Alternator bearings tend to 'whine' when they are starting to go. A good way to check is to find a quiet spot. With engine running (all lights and accessories off) note the pitch. Then turn on your headlights (on bright), then off, then on. This puts a load on the alternator and you will notice a definite change in the volume and pitch of the sound if the bearings are bad.

IF a 'Whiring or grinding sound, it can be any pulley/tensioner associated with the serpentine belt (if you are lucky) OR worse, something involving your timing belt or water pump (MUCH harder to get to).

Idler pulley bearings and tensioners on the front of the engine are most often the source.