My 912e motor has two pulleys on the outer edge of the fan ~8" and a third (much smaller...3.5") that runs off a Rube Goldberg setup that bolts to the fan hub, brings the power out past the edge of the other two, has a bearing & holder arrangement then the pulley.
Only one is used to run the Alt. Which one runs the A/C? What is the third for?
Finally, could the A/C be powered directly from the crank hub in the space behind the air chambers?
TIA!

sounds like you have a pulley for the A/C, a pulley for the alt, and a pulley for the emissions air pump. if i remember correctly, the A/C pulley goes between the fan and the hub that mounts it to the crankshaft, the pulley for the alt is just the big groove that is the same diameter as the fan and the emissions pulley sticks out from the center of the fan.

at least on the 914 type IV motor, the A/C pulley is as described above. i would think that the 912E type IV mounting of the A/C would be the same as the 914.

The A/C pulley is behind the fan. You can't see it with the fan installed. Cars w/o A/C have a spacer instead of a pulley. The pulley on the extension bolted to the outside of the fan hub is for the air pump. The Cap'n

On a 912E the A/C unit is driven off the outer pulley the larger of the two

the inter pulley drives the smog pump. On a 912E the A/C unit is mounted

on top of the engine not on the side like a 914.