Dear volvo426,

Hope you're well. Per your description, the accessory drive belts are installed correctly. The air-conditioning compressor drive belt (outer-most, i.e., closest to the radiator) and alternator drive belt (in the middle) are separately-driven. Each has its own belt. The third belt (closest to the engine block) drives the water pump and power steering pump.

Keep the belts properly tensioned. To determine proper tension, use an index finger to press on the belt, midway between the crank pulley and the alternator, water pump, etc. You should be able to depress the belt by 3/16".

Once you've tensioned the belt and tightened the nut, that locks the tensioner, loosen the 10mm hex-head long bolt, that sets the tension. This prolongs the life of that bolt. To the same purpose, coat the long bolt's threads with anti-seize. Anti-seize helps to keep the tensioner's long bolt from becoming corrosion-bonded to the tensioner's lock bolt,

Further, inspect the rubber mounting bushings for the alternator and air-conditioning compressor. If a bushing's bolt hole is egg-shaped, it is time to replace the bushing. Another way to assess the bushings is to look at the belts from the side of the engine bay. Each belt should be parallel with the others, and also with the front of the engine. If a belt is skewed, i.e., is at an angle to the front of the engine, the mounting bushings likely need to be replaced.

Presume good quality drive belts have a service life of five years. A set of belts - made by Contitech - can be had from FCPGroton for about $25. When installing new belts, I write the month and year at several places on each belt, using a magic marker. That is a reminder as to when the belts should be replaced.

Hope this helps.

Happy Holidays and a Good, Healthy New Year!!

Yours faithfully,

Spook