I have come across a variety of pulley options on Y-Block Dampers and Accessories (alternator, fan, air compressor, and power steering). I tried searching the site to make sure this subject had not been previously addressed and did not find anything specific.  Do the dampers and accessories come in two widths (3/8" and 1/2")? I would assume the damper would determine what size pulleys should be used. In my search, I have seen some engines with both, which I would think could be a problem for belt wear. Some of the vendors for air compressors, alternators, and power steering pumps I have came across made no mention of an option when it comes to pulley size (width). I'm looking for some help to understand this. I do believe its possible to swap out any of the pulleys, damper being the most expensive.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

i'm no expert so you may have to confirm this

readily available pulleys appear to be 3/8     early stuff ie pre 56 may have been 1/2  some truck stuff was 1/2 and the water pump had a 3/4 shaft as opposed to car 5/8

stuey

Up through 1956, the belt sizes on the car dampers were ½”.  Starting 1957, the belt size at the damper downsized to 3/8”.

Lorena, Texas (South of Waco)

Thanks for this information. I have two double pulley dampners now so I should be covered to rebuild the 256 (54 Merc) and the 292 (63 Ford PU).

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's

How often do the 1/2 inch pulleys get crossed up with the 3/8 inch pulleys. My relative little exposure to these engines I have found quite a large number using them together. I felt going one way or the other would be better than mixing them on the same engine block.

Darrell Howard Whitefish, MT Outlaw 56 Ford F-100's