3-Series (E46, E90)Chat relating to the BMW 3-Series from 1999 to Current. Models include: BMW 316i, BMW 318i, BMW 318Ci, BMW 320i, BMW 323i, BMW 325i, BMW 330i, BMW 328 Ci, BMW 328i, BMW 325i/xi, BMW 330Ci, BMW 320d, BMW 330d, BMW 335d.
I purchased my 2000 BMW 328CI this pass summer. At the time it had a small belt noise when I started the car but would go away after driving it for a half hour or hour. I started doing some research on the internet, most of the information I found point to the pulleys.
Last night I looked at my engine to see the layout of the belt, noticed 2 pulleys on the belt drive for the water-pump/alternator. One pulley is on they Hydraulic belt tension-er and the other is Deflection pulley, the names I got from an online diagram from realoem but are also known as the idler pulley and belt tension-er pulley.
After studying the diagram plus my engine, I concluded that the pulleys could be changed. There was no reason to buy a new complete hydraulic belt tension-er kit although it sells on eBay for only $98. Thinking logically and the strain the economy has put on me, it made sense for me to buy a belt pulley set from eBay for only $27.
That's definitely worth the time and effort, but for those who have more time than money, I would suggest taking the old pulleys out and repacking them with grease. Not an expert but would suggest a high temperature wheel bearings grease possibly marine.
I haven't mentioned the third pulley on the belt drive climate compressor, an adjusting pulley also known as a belt tension-er. According to the diagram the pulley can't be separated and need to be bought as a whole part. I haven't confirmed this but will soon.
I say there is a 3-step process trying to figure out the noise.
#1. Take the belt off on the belt drive climate compressor. This is only needed for air conditioning and won't be missed for the time being. Drive it around a few days, still making the noise then this is not the problem.
#2. Best bang for the buck considering time and money. Order the belt pulley set and replace both pulleys, one is the hydraulic pulley and the other is idler pulley. If not concerned, only order one of the two. If that's not it order the other one. Now you've replace both pulleys and the noise still continue.
#3. Use an automotive stethoscope to see if the noise is coming from the hydraulic belt tension-er area, it cost around $10. If so replace the replace the whole thing with a new kit or only the Hydraulic belt tension-er. Not much of a price difference depending on where you buy it. This is the most expensive part so do careful research on prices and that you've determined that this might be the problem. After having replacing the pulleys I don't thing this will be an issue.
I haven't started on the steps yet because I'm waiting on the pulleys to arrive but will document everything and post it here. If the noise went away when you took the ac belt off then just purchase a new adjusting pulley that cost around $50.
My things came in today that I ordered from eBay. A 32mm wrench, hub holder tool and tension-er pulley. Decided not to get the pulley kit since I noticed that the idler pulley has been recently replaced. Had a difficult time using that piece of shit crankshaft pulley hub holder tool, probably would of had an easier time with a long piece of metal like a screw driver. Now the hard part is over, the pulleys are easy to remove,idler pulley screw is long but not the tension-er pulley.
Normally the pulley's have a dust cap on them, mine didn't have 'em. I went online and ordered them through pelicanparts, Protection Cap for Drive Belt Deflection Pulley $2.50, and Protection Cap for Water Pump and Alternator Belt Adjusting Pulley $2.50. I didn't have a dust cap on the tension-er screw either, decided to order that also, PROTECTION CAP $1.00
I started messing around with the old pensioner pulley to see if I could repack it with grease. Was able to take the ring off, noticed not much grease in their, needed replacing, I repacked it with grease, tested it and it works. Since I had a new I installed that one instead. The idler pulley I was able to repack too, didn't need it but decided to put more grease in it, reinstalled it.
Since I had my tools out, I decided to change out my sparks plugs, didn't take no pics. I put it all together and started the car. No more noise, wait, wait that tiny noise I hear, sounds like it's coming from the water pump pulley. Someone's advice online was to spray it with WD-40, the noise went away, thinking I might need a new water pump pulley or maybe a new water pump.
Does anyone here know if the water-pump is going out, if it would make a noise, or give any signs that it's going out?
Well I drove my car around, this time it's making a different noise then before, weird thing is something seems to seize up. I can smell burnt rubber like one of the pulleys ain't spinning. Only two things left to check, alternator and water pump, noise also seems to be coming from inside the engine, makes me believe it's the water pump.
Well decided to take apart the car again, this time the alternator. Took it to autozone, had it tested and it passed with flying colors except the damn thing was making the noise. I finally found it...woot...woot. According to autozone the bearing are going out and probably seize. I asked him if I could repair it, he said no...lol, a new reman would cost over $200. Yeah right, I went home took it apart, the problem was the bearing. Found it on eBay for $5 and the other for $15. Here are the pics
On the alternator the front bearing needed repacking. I should of left the back bearing alone but didn't know at the time. The back bearing was harder to take off plus I end up breaking the brushes, also it's a harder bearing to find, it cost more too, $15 from online at bearingsdirect. Getting to the back bearing I striped two heads, drilled them suckers out, now missing two screws...lol. Should of took my time and adjusted my speed on my drill.
In all it was pretty easy, the parts for a rebuilt kit is kinda hard to find, in my case all it needed was bearings. I haven't received my bearings yet and waiting to see how this alternator works but thinking I'll save em' for down the road just in case. Tomorrow I need to get new bushings, don't know where, I'll make some phone calls because I can't find em' online.
The brushes for the alternator was hard to find, file it down to make it work, took it to autozone and it checked out. Put the alternator back in my car, sounded good then the freaking noise came back. The grease from the bearings was flying all over the place...lol. My guess that the seals came off, thinking about it the orientation might off been wrong, guess it was a bad idea...lol. I already ordered the bearings just waiting for them, was hoping this would work until then but my car showed no love.
You can't go wrong with new bearings especially if they only cost $5 for the front bearing and $15 for the rear bearing. That's better than paying $225 at Autozone or paying around $150 to get it rebuilt by a shop that's 1/2 hour away.The shop don't carry any the parts in stock so they would have to order it, if there was more than just a bearing problem then I'd probably get it rebuilt by the shop. If I had time I'd order the parts from woodauto but then it'll take a few days to get here. Why fix if it's not broken...lol.
109,000 on my BMW, got another 200,000 miles to go...lol
My new bearings came in for the alternator. Replaced the old ones, took to autozone to check it, bearings still making noise. I took the alternator apart again, took the seals off the new bearings, not much grease there, the guy at autozone recommended "Red N Tacky#2 Grease" (lucas brand), repacked the bearings. It worked! Now my car is making a noise again but it's the damn belt. I put belt dressing on it and the noise went away, gonna buy a new belt 2morro. I figured the belt probably was gonna be an issue because when I took it off, the shape was molded like it was sitting there for a long time without being used.
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