Possible Alternator Pulley Failure - Bearing Noise From The Engine Bay

Có thể bạn quan tâm

Menu Log in Sign up

Home
Forums
Technical
Engines & Transmission

JaseZA

So I have an obvious and new whine from the engine bay. As far as I can tell it sounds like it's coming from the alternator. Initially I thought it was diff whine but then I noticed it is directly related to engine speed and I can hear it when I have the car idling and open the bonnet. I first noticed it this morning on my way to work. Interesting thing is that we've been having huge amounts of rain and experienced some flooding. The farm road I use to get to work was flooded and I ended up wading through about a meter of water at one point! Caught me seriously off guard when the bow wave briefly crested my bonnet!! Definitely the deepest I've been in the Tiguan. So I'm assuming some water got up into the engine bay. Now it's interesting that it seems the alternator is making the noise and not the AC compressor, which is lower down... Tomorrow at work I'll take the serpentine belt off and "feel" all the pulleys and bearings and see if I can determine what's running funny. I've googled a bit and can't find much info on the alternator in the Tig and what bearings it takes. I'll look up the numbers on the alternator tomorrow. Basically this post was to check if I'm missing anything obvious and if anyone has more info on the alternator in our Tigs. #1 · May 17, 2018 So I have an obvious and new whine from the engine bay. As far as I can tell it sounds like it's coming from the alternator. Initially I thought it was diff whine but then I noticed it is directly related to engine speed and I can hear it when I have the car idling and open the bonnet. I first noticed it this morning on my way to work. Interesting thing is that we've been having huge amounts of rain and experienced some flooding. The farm road I use to get to work was flooded and I ended up wading through about a meter of water at one point! Caught me seriously off guard when the bow wave briefly crested my bonnet!! Definitely the deepest I've been in the Tiguan. So I'm assuming some water got up into the engine bay. Now it's interesting that it seems the alternator is making the noise and not the AC compressor, which is lower down... Tomorrow at work I'll take the serpentine belt off and "feel" all the pulleys and bearings and see if I can determine what's running funny. I've googled a bit and can't find much info on the alternator in the Tig and what bearings it takes. I'll look up the numbers on the alternator tomorrow. Basically this post was to check if I'm missing anything obvious and if anyone has more info on the alternator in our Tigs. See less See more Sort by Oldest first Oldest first Newest first Most reactions #2 · May 17, 2018 Keep in mind that the pulley on the alternator has a one way clutch in it and that’s what might be making the noise. #3 · May 17, 2018 Okay interesting. How would I test this? Just check it rotates one way and not the other? I guess I would need to stop the internals of the alternator turning as well? #4 · May 18, 2018 So I checked out all the pulleys on the auxiliary belt this afternoon and all appear to be working smoothly and correctly. The alternator clutch pulley is definitely free moving one way and locked up in the other direction (when locked in position with a trim tool in the cooling fins) which is how it should work as far as I could determine from google. Unfortunately this only leaves pulleys I couldn't get to which are timing belt idlers... So I'm going to get it up on a ramp next week to have a better look. #5 · May 18, 2018 Having a timing belt pulley make noise is quite rare, but does happen. Having an idler or tensioner pulley fail is way more common. Remove the serpentine belt ans spin them by hand and feel for play. if you hear any noise, replace the pulley. they should be almost silent if ok. While the belt is off, you could start the engine and listen for timing belt area noise. You won't be able to check by had becasue the timing belt is under tension and you can't mess with it, without the proper tools #6 · Jun 21, 2018 Okay, so I've finally had time to have another crack at this and can confirm it is definitely the aux belt tensioner that is making the noise. Busy trying to find a replacement. Just had a look at it and I have no idea how it come out!? There don't appear to be any bolts holding it in? Maybe it will be obvious when I'm holding the new one, but does anyone have a clue how it works? Here is a link to one I found online: https://www.ecstuning.com/b-litens-parts/tensioner-assembly/038903315ah~lit/ #7 · Jun 23, 2018

JaseZA said: Okay, so I've finally had time to have another crack at this and can confirm it is definitely the aux belt tensioner that is making the noise. Busy trying to find a replacement. Just had a look at it and I have no idea how it come out!? There don't appear to be any bolts holding it in? Maybe it will be obvious when I'm holding the new one, but does anyone have a clue how it works? Here is a link to one I found online: https://www.ecstuning.com/b-litens-parts/tensioner-assembly/038903315ah~lit/ Click to expand...

I seem to remember there is an allen bolt that holds it in from the back, it's a PITA to get at but it can be done. Mick #8 · Jun 23, 2018 So I can confirm that it is a serious PITA! 2 hours yesterday of lying on my back on the garage floor trying to get to that allen bolt (didn't know what it was at the time though) and I eventually gave up because I ran out of time. So I've just changed the pulley and bearing and that has made a big difference to the noise. I think to get to that allen bolt you have to remove the pipe from the intercooler to the intake manifold, but everything is quite tight to get to. If I'd had a rachet with an angled head I could maybe have just gotten in their, but with my limited home tools, it was rather tough! This one will have to wait until I can get the car onto the work lift with all the extra tool options! Insert Quotes Post Reply

posts 147K members 28K Since 2007 A forum community dedicated to VW Tiguan owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more! Show Less Full Forum Listing Explore Our Forums General Discussion Problems, Bugs & Fixes Modifications & 'How to' Guides Electronics New Members - Important Info & Introduction Area