I have a 1987 Coachman motorhome with a Chevy 30 one ton chassis. The motor is a 350V8. The air pump is missing the v-belt. There is a single pulley in line with the air pump right behind the fan blade that is also unused. The Haynes book seems to show the v-belt routing around the fan pulley, the air pump pulley and the alternator. However, the alternator is not in line with the other two and is powered currently by the surpentine belt. It would appear that the belt should be between the two current vacant pulleys. The problem remains that there is no apparent way to tension the belt as the air pump is hard-mounted in one position. I could use some help figuring the correct way to get the air pump working as I cant pass the smog test in it's current configuration.