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Belt noise - Is this right?
https://forums.tipec.net/viewtopic.php?f=25&t=21245		 Page 1 of 1
Author:  rav [ Fri Apr 08, 2016 7:59 pm ]
Post subject:  Belt noise - Is this right?
I am quite worried about this, so i started a thread of its own, rather then burried in my build thread. Admin - i hope that this is ok?

I noticed a strange noise from the belt area on my car today. You might recall that i bought it in February and have not started it for a month or so.

I noticed a high pitch sound and video'd it to try and capture the sound.

http://s123.photobucket.com/user/rsb377/media/NBZ%207920/VID_20160408_142209_zpspsiccn0n.mp4.html?o=0

Any ideas what this could be and how to fix?
Author:  Matt749 [ Fri Apr 08, 2016 8:29 pm ]
Post subject:  Re: Belt noise - Is this right?
Water pump? I'd get the belt cover off and have a good look around. If the double sided toothed, balance shaft belt is tensioned to spec it can whistle a bit but the sound your recording shows is not the same. Better check than be sorry later.
Author:  flt505 [ Fri Apr 08, 2016 8:51 pm ]
Post subject:  Re: Belt noise - Is this right?
That's a whirring and a whistle! (Sounds like mine when I bought it!). Replace all your belts, rollers and bearing wheels and water pump. Also, while you there, replace all of your ignition system - plugs, HTs, coil, rotor arm and cap - the difference is quite amazing! It is worth the expense.

Dave
CT
Author:  blackadder30 [ Fri Apr 08, 2016 10:21 pm ]
Post subject:  Re: Belt noise - Is this right?
Sounds like two different things at the same time.... A squeaky PS or Alternator belt and a whirring bearing? A stethoscope (or long screwdriver) can help pinpoint exactly where it's coming from....
Author:  PSH [ Fri Apr 08, 2016 10:27 pm ]
Post subject:  Re: Belt noise - Is this right?
what 'blackadder' said...:)

Pete
Author:  AlpineTurbo [ Sat Apr 09, 2016 8:50 am ]
Post subject:  Re: Belt noise - Is this right?
IMHO alot of people are getting ahead of themselves.

If you really want to see what is at fault get some 'belt squeak' or if you really want to be unpopular WD-40 but with a straw attachment and spray it onto the alternator belt (IMO it will be the belt that is making the noise). If it goes down you know for certain it is the auxilliary belt that is making that noise. Another way would be to remove the belt and run the car to see what happens.

My 106 GTi which runs the same belt arrangement as a 944 made the same noise, because the previous owner 'forgot' to put on a new belt and put a very old belt on ; maybe the belt was new to the car. After a belt swap it was fine :).
Author:  Endoman [ Sat Apr 09, 2016 7:44 pm ]
Post subject:  Re: Belt noise - Is this right?
New belts one idler roller replaced and it still sounds like a washing machine. I'd love to get rid of it but after 4 attempts by self, 2 indies and OPC (no really) still there. Can't hear it inside, the break squeal is something else though.
I wouldn't worry too much if the belts are newish and the rollers have no lateral play. By all means replace the lot for peace of mind but don't be surprised if it still sounds like a Bendix.
Author:  tr7v8 [ Sat Apr 09, 2016 8:10 pm ]
Post subject:  Re: Belt noise - Is this right?
I would drop the aux belts off and see if stops. We had a member on here with a car a few years ago. We told him to stop using the car as it was making a screeching noise. When I stripped the water pump off it was sha99ed. Spinning it it sounded like a cheap Chinese ratchet, the bearings were beyond shot.I suspect a few miles the pump would have seized and stripped the belt. He was very lucky :oops:
Author:  Waylander [ Sat Apr 09, 2016 9:14 pm ]
Post subject:  Re: Belt noise - Is this right?
As Jim suggests one belt at a time to see if the noise stops
Author:  flt505 [ Sun Apr 10, 2016 9:02 pm ]
Post subject:  Re: Belt noise - Is this right?
I have to humbly disagree with some of the advice given here. But I will be quick to suggest that all front belts, should be changed at the same time, or as in the recommended Porsche maintenance schedule. The belt rollers and their associated runner bearing wheels are not a service replacement item, unless deemed appropriate by a full-on mechanic. Therefore - taking off a aux belt to find a 'bad' roller etc and thus replace one problem, seems an odd way to go, as most of these items have the same attrition rate.

When I bought my 944S2 some years back, the engine sounded appalling (a tractor someone mentioned, standing next to it!) Subsequently soon after, all the belts, rollers etc were replaced - the whole lot were just knackered. Itemising the problem was not the issue - just replace the whole lot and no fiddling around...

Others here will comment obviously - but that was my way of sorting noisy belts...

Dave
CT S2
Author:  Waylander [ Mon Apr 11, 2016 9:43 am ]
Post subject:  Re: Belt noise - Is this right?
it was a suggestion to find out if it was an aux belt or associated accessory, Alternator or PAS pump.

if the noise continues after removing those then full belt and pump job is the order of the day
Author:  rav [ Mon Apr 11, 2016 11:46 am ]
Post subject:  Re: Belt noise - Is this right?
Thanks all.

I tried the WD40 on the belts I could see (not balance or cam) and the noise goes away for a short while, but comes back again within a few minutes. I had my daughter to video this, but at 1m15s I can find no easy way to upload it to here.

I checked the tension on the belts that I had sprayed with WD40 and they seemed fine to me, if anything - perhaps a little loose?

R
Author:  Waylander [ Mon Apr 11, 2016 11:57 am ]
Post subject:  Re: Belt noise - Is this right?
Now you have put petroleum based lubricant on a rubber belt, time to change the two belts, cheap as chips from euro car parts

Do them both but start the car in between, it could be that one is out of line, PAS pump can loose it's spacer and twist
Author:  AlpineTurbo [ Mon Apr 11, 2016 6:15 pm ]
Post subject:  Re: Belt noise - Is this right?
rav wrote:
Thanks all.

I tried the WD40 on the belts I could see (not balance or cam) and the noise goes away for a short while, but comes back again within a few minutes. I had my daughter to video this, but at 1m15s I can find no easy way to upload it to here.

I checked the tension on the belts that I had sprayed with WD40 and they seemed fine to me, if anything - perhaps a little loose?

R


IMHO I reckon you have your answer there :). However, just for insurance I would run the car without the PAS and alternator belt and see if the noise is gone. If it is happy days. The noise will always come back despite the WD-40 or Belt squeak stop, since the belt ultimately is either wrong or more likely, worn.

I have had loose aux belts on cars (my Escort was one of them; it came to me with the wrong belt) and if the belt is of good quality it should not squeal.

But, I would also check the alignment of the pulleys as Waylander pointed out.

If it's had the belts and rollers done why spend that cash to redo them again when they were never at fault? People must love burning cash. IME most garages will not change the auxiliary belts when a cambelt is except for three reasons :

[*]You ask them to do it
[*]They were noisy when the car went in
[*]The service schedule explicitly tells you to do it and there are repercussions of not following it ; The Clio 172 and 182 are a good example of this (if the aux belt breaks there is a high chance of it going into the cambelt with pretty obvious results).

My dad's Mondeo 2.5T (Volvo engine) had the cam belt changed by a specialist with the same aux belt. If I am honest, I think most of my cars were fitted with the old aux belt (Pug 306 GTi-6, Pug 106 GTi, Pug 205 GTi (previous owner), Ford Focus 1.6, Pug 306 1.9 TD, you get the idea).

On two cars I had pretty serious sounds where I thought it was game over. In most cases I was fine.
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