924Board.org

[cliff kent]

I have a 1985 924 lux and it has started to devour fan belts. Under normal conditions all is OK but if I load the electrical system eg, lights, wipers, rear window demist and heater fan the volt meter drops and the fan belt starts to skid on the alternator pulley. I understand that the alternator is under load at this point but I don't think it should cause this problem. Any ideas ?
Also when I bought my first replacement belt (from Porsche dealer) I was given an 888 belt ( the original was also an 888) but on trying to fit this it was impossible as there was not enough adjustment in the alternator eventually I found a slightly longer belt that would fit any ideas why the 888 wouldn't

[ This Message was edited by: cliff kent on 2001-10-07 01:45 ]

[Guest]

My fisrt reation is that the battery is getting weak and when under a load tries to get power from the alt. In theory your battery should be able to run all the accesories for quite some time on it's own. Try putting a volt meter on the battery and run heater fan or another accesory. If the battery drains quickly below 12V this is a good indication your battery needs replacing. This is only one of many possibilities.

[924RACR]

I always have to remove the water pump pulley to change belts, it won't slip on otherwise.

However, I don't think not using the 888 belt is your problem; most likely the pulley on the alternator is worn smooth from the belt slipping too much. I recommend you use sandpaper on the frictional surfaces of the pulley to improve the grip. I also recommend you make sure you have new alternator bushings - you will not be able to tension the belt properly if they're worn and flex. Trust me I know - I've DNF'd races because of this.

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype