turbo510

I recently wrote that I prefered to err on the side of looseness when tensioning the 2.8 12V's timing belt. I found that this isn't a good idea, because once the new belt's teeth smoothed out and settled into the sprockets, the belt slacked up. The 12V doesn't have an active tensioner, so it doesn't compensate for wear or stretch. My engine had a chatter at idle and low rpms when cold, which became quieter when hot. I thought this could a defective water pump, but then I noticed how much the belt was flopping, and the polish marks inside the belt covers where the belt was touching. Instead of 90 degree twist, the belt could be turned about 120 degrees! I reset it last night, and the motor is now quiet like it should be.

old96A4

I think on the down side of tighting the timing belt is if to tight wears out water pumps to soon. Happened twice to me now, unless these water pumps are defective. I had one go at 50K miles and the last one go at 26K miles. bearing the first time and the last time it was the seal.. Maybe this stuff is junk now, but still both made in Germany...