Bothersome belt
u The owner of this 2003 Citroën Relay van was a plant maintenance engineer and so not afraid to get his hands dirty. He had heard the auxiliary drive belt whining and was intending to replace it soon, but while driving around he saw the red ignition light glowing. Pulling over he realised that the auxiliary drive belt had popped off. Fitting it back on again he made a detour to pick-up a new belt and carried on intending to fit the new belt later in the day. It was only a few miles further along his journey when the belt once again popped off.
This time he fitted the new belt and went about his business. That was not the end of the story though as once again after a few miles the new belt came off. This time he asked me to have a look to diagnose why the belt kept flying off.
The problem turned out to be a worn tensioner bearing, which was allowing the tensioner pulley to kink over to one side allowing the belt to slide off as it went around. At just over £80 for the new tensioner it was a bit more expensive than the belt he was expecting, but at least this time the belt stayed in place.