V-belt chirp

[Hans Efde]

The drive belt on my Convertible chirps. It's like I have a birds nest under the bonnet! I hear it all the time, not just when accelerating. Tension was fine, but the sides were shiny. I put a few white marks on the waterpump pulley and belt and noticed some slip. I put a new one in, tensioned it properly but it's still chirping. By Googling I found out it can be misalignment. I'll check this evening by spraying water on it:
http://www.youtube.com/watch?v=X9qMtVVLXeY
and see it still chirps.

But has anyone experience with adjusting the pulleys of the generator or waterpump? I wouldn't now how to do that since there are no adjustment devices. Possibly I can shim the generator but that's it. Does anyone have experience with this complaint? Can it be something else? Without the belt the generator and waterpump run smoothly without play.

[manifold]

Hans your right. They are often out of line. you can shim the alternator and water pump pulleys with spacers.....make them yourself with ally and washers. only bottom pulley is generally fixed......unless you have a cooper S 2 piece/ fischer type damper.

[Hans Efde]

Pulleys look to be lined up properly. I checked it with a ruler. Next I tried the torque wrench test as described in the Haynes. The generator should start to slip with about 10 to 11 lbft clockwise. Mine starts to slip way earlier (I have to say 10 lbft is quite a bit for a drive belt to hold). I tensioned the drive belt as high as possible but still it slips below 10 lbft. I even can't get a reading on my torque wrench, even the lowest setting slips. Perhaps the pulley is a bit greasy or the drive belt too new. I let the car run for a while (although stationary it doesn't chirp) and sprayed brake cleaner on the pulleys. If it still chirps on the next drive I'll find some chalk powder to increase the grip.

[Hans Efde]

It's not the V-belt. The noise is present when the car moves. With the car moving and the engine in neutral it can be heard. It can also be heard with the car moving and the engine switched off (gearbox in neutral). Clutch in/out does not make a difference. So it must be the drivetrain, driveshafts, bearings, brakes etc. I checked the brakes and replaced the pads to be sure. Although the left brake has a slight noise at a certain point it's more a grinding noise than a high pitched whistle. Changing the pads didn't change it. Also when the car is moving and I press the brakes the sound doesn't change. I would expect that if it would be coming from the brakes. I am going to put the front of the car on stands and swing the wheels as fast as I can to see if I can replicate the noise. I would expect a problem with the diff or the hub bearings. Positive point of this complaint is that the birds start singing when I drive past.

[Geoff Butcher]

It's not the V-belt. The noise is present when the car moves. With the car moving and the engine in neutral it can be heard. It can also be heard with the car moving and the engine switched off (gearbox in neutral). Clutch in/out does not make a difference. So it must be the drivetrain, driveshafts, bearings, brakes etc. I checked the brakes and replaced the pads to be sure. Although the left brake has a slight noise at a certain point it's more a grinding noise than a high pitched whistle. Changing the pads didn't change it. Also when the car is moving and I press the brakes the sound doesn't change. I would expect that if it would be coming from the brakes. I am going to put the front of the car on stands and swing the wheels as fast as I can to see if I can replicate the noise. I would expect a problem with the diff or the hub bearings. Positive point of this complaint is that the birds start singing when I drive past.

That's just because they're excited to see a Midas!

[wolfie]

check neither of the back plates behind the discs is slightly touching and there's no crap trapped between these 2 things

[Hans Efde]

check neither of the back plates behind the discs is slightly touching and there's no crap trapped between these 2 things

I checked those. Yesterday put the car on stands and the wheels are spinning without any noise. This morning I thought if it could be the speedo cable. Indication is jittery and it is the only thing that keeps on turning together with the wheels when the engine is shut off.

[manifold]

if its doing it with engine switched of it might be worth checking the inner cv joints and the splines inside the hub...which can also cause this due to slight movement. one sign is slight metallic fragments next to the split washer near the hub nut.

Also is it a verto or preiverto clutch. The pre-verto release bearing can make this chirping noise if it needs backing off with the little return stop and/or the bearing is running dry...just before its about to let go..... all worth checking out just to eliminate.

[Hans Efde]

I found it. I disconnected the speedo cable from the engine and rotated it by hand. I got the chirp. I tried to poor oil in the cable but was only partially succesful. After connecting again I tested the car. Speedo indication was more stable but still the chirp. Then I pulled the cable from the instrument pod and all was quiet. So it seems to be coming from the speedo! It is a "new" one with km indication I recently installed, so possible it has been on the shelf for a few decades and it has dried out the mechanism inside. I''ll pull it apart coming friday and see.

[Hans Efde]

Last weekend I took the instruments apart and started oiling all moving parts. In the end I found it, a horizontal shaft that rotates in the housing, see screwdriver pointing:


I testdrove the car today and the good news was that the chirp was gone. The bad news was that I oiled something I shouldn't have oiled and the speedo went bazerk indicating at least 3 times the real speed. Luckily after about 20 miles it came back to normal values. Phew, almost ruined a good and rare speedo with KM indication.
Unfortunately I must have damaged the hazard warning switch during removal of the speedo, because that won't work now. I hate that thing anyway, so perhaps I am going to rewire it to a location on the dashboard.