Fan Belt

[peter212693]

Hi all

the other night I posted about my RPM dropping when I have my electrics on Lights, radio, heated screen and blower enough to make the car shake a little. So i took it to a garage I know and they tested the battery from idle, 2000Rpm with electrics on etc and it was OK so he said the fan belt needed changing as it was quite old and slipping a little.

Now I have changed it and around 3000Rpm there is quite a loud whistling sound can anyone tell me what that is?

Also it hasn’t seemed to sort the RPM dropping problem out any other suggestions?

Thanks

 

[peter212693]

Still sounds to me like the battery is no good or the alternator is on it's last legs and isn't charging the battery. If the battery's not a sealed for life type, take the screw plugs out and see if you can get someone to drop-test it for you. If you see any of the cells fizzing or the voltage drops too low when it's drop-tested then it's new battery time. Also, to test the alternator, you could get a multimeter, put one probe on the volts output of the alternator and one on a grounding point. It should be at least 12v on tickover and should rise to 13ish volts when everything is switched on. If the voltage drops on the alternator output then you might be looking at a new brushpack (cheaper than an alternator complete)

I had the battery tested today and was perfect 13.5v when off and about 14v when engine running the guy said the battery was fine. The car is nearly 10 years old now could be the alternator

 

[peter212693]

If that is indeed the case then yep it sounds like the alternator, as you say.

How tight does the belt have to be on the alternator and any idea what the whistling sounds is it makes?