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Belt Whine

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Old 06-05-2004, 05:24 AM
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Race Bred
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Default Belt Whine

Is a small but noticeable amount of belt whine normal with these cars? I have all of 200 miles since the head tear down and I re tensioned the belts yesterday but there is still a whine. The water pump was tight when I had it out and is pretty recent... Could that going bad cause the whine? Also the rollers and tensioners are new (200 miles ago). For torque values on the belts I used 40 lbs for the timing belt and alternator belt then around 27 for the balance shaft belt with the kricket based of the values on www.arnnworx.com. Any thoughts or should I just get used to it? Also dose anyone have an alternator/ ac crank pulley for sale (83 N/A) mine has a nick in one of the groves but I doubt this is the cause of my whine.
Old 06-05-2004, 08:40 AM
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seb928s
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Some whine because the belt is to tight and in some cars the whine never goes away ask me how I know just ask.
Old 06-05-2004, 10:22 AM
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IceShark
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Did you mean to say that your alternator belt is at 40 pounds of tension? The alt/ac belt is supposed to be at 85 lbs. If you have it at 40 it will eventually start to screech for awhile on startup and probably like a banshee when the A/C clutch kicks in.

You have new belts so the whine may go away as they stretch. After going through this with used belts and reading everything I could find and asking questions I concluded: whine can be from too tight or too loose but usually too tight; the balance shaft belt is usually the one whining; the Kricket tool is sort of a POS; you have to keep the measuring nub of the Kricket on one of the teeth on the B/S belt, not in a grove; make final fine tuning with the front open, run the car and listen, tweek a bit more, run the car, tweek a bit more, etc., etc., and finally talk yourself into the position that some very soft whine is normal.
Old 06-05-2004, 11:57 AM
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Mine has whined for 2 1/2 years, through 3 different belts and sets of rollers, almost sounds like a blower at times.

Mech. says not to worry so I got used to it.
Old 06-05-2004, 12:58 PM
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Well the reason I know is that a shop a guy that has been in business with German cars since way before I was born said "Some cars have the whine others don't with the right tension.". Basically it's normal for some of the 944 cars have a little whine with the tension right on the money using P9201 tool and others won't have this. I don't know why some do this and others don't. With new rollers and all still there is a whine on my 951 and ever since I bought the car it had one.
Old 06-05-2004, 01:05 PM
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In my case, I myself, replaced the waterpump/rollers/belts. It had a lot more whine to it then I thought it should afterwards. 347 miles later, while trying to diagnose this and other noises up front, I noticed that the timing belt I installed (.75" wide) was riding off of the aft side of the pulley of the rebuilt water pump that I recently installed (updated 951 style) about a .1". I ordered a brand new pump, and in comparing the pulleys and their placement on the waterpump between the rebuilt one that I just put on car, the original non updated pump I originally took off the car, and the brand new pump I just ordered. (and I took pictures of this comparison). The rebuilt pump (updated style), had the old style/narrower pulley installed on it, and the belt flange on it was positioned approx. a .1" to far to the fwd side, as compared to the original non updated one. the flange was lined up with end of pump shaft on the rebuilt one, but inset .1" on original pump that was using the same size pulley on it.
The timing belt showed this .1" wear pattern on the smooth side of the belt. After installing the brand new pump with the wider pulley on it, and knowing the belt was making full contact with this wider pulley, the "belt whine" was greatly reduced, with just a "small amount" noticeable.

Lesson learned: make damn sure you check the alignment of, and contact points of your belts on all pulleys, gears, and rollers before you consider yourself good to continue.

My very limited experience says that yes, some "small amount" of belt whine is normal. But there is a definate point at which one MUST be concerned. HTH
Old 06-05-2004, 02:10 PM
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I rentensioned mine as part of my waterpump job.

Sounds like I have a supercharger under the hood, AND a turbo Im getting a shop to check them for me, I dont want to risk it all just yet.
Old 06-05-2004, 02:17 PM
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ERAU-944
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hey seb, how about using some punctuation?

and belt whine is normal, all of our cars have it. i get suspicious if it whines loudly, as it generally means there's too much tension on one of the timing/balance shaft belts.

i wouldn't worry too much, as long as you know the belts are tensioned to spec. just retension again at 1500 miles, and then again at 15000.

-Mike-
Old 08-27-2011, 06:35 PM
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pacemaker63
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Mine sounds more like a buzzsaw. This is my first time changing the belts. So how do you know "what's TOO much tension whine?"

https://www.youtube.com/watch?v=x6VE...layer_embedded


Somebody please tell me if if that sounds too tight or not.
Old 08-27-2011, 10:17 PM
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Originally Posted by ERAU-944
hey seb, how about using some punctuation?

-Mike-
And yet you didn't capitalize a word of your post...



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