1948 f1 with a 226 h-block, multiple previews owners...

A previous owner of my truck installed one of the vintage air kits. That's all well and good except the fact that the belts are messed up. It looks like the crank and the fan are both the original pulleys, which as I understand it are for 7/8 width v-belts. The issue is that the (sanden?) AC compressor is a double pulley which then runs up to the alternator, but the double pulley is for half inch belts, so they're just running a narrow belt on the two original police (a 15430) That has the sad effect of bottoming out instead of riding on the sides, and I cannot get enough tension on it for it not to squeal horrifically about 40 miles an hour. So I'm left with the question of do I replace the crank and fan pulleys with narrow belt ones? Or do I swap the pulley on the compressor (and potentially the alternator - is there even a AC clutch pulley setup with one line and one narrow belt?) to run wide belts?

My initial quick searching has not found solutions for either of these directions. Obviously I can switch to an electric fan if that's a real issue, but I don't feel like that should be my real stopping point? And frankly I'm trying to keep as much original-ish as I can as long as possible, the more mechanical the more better.

 

I don't have this setup, but I would try a 3/4" belt over the ~1/2" belt you have now.

 

I don't think they had A/C back in 1948 so you are stepping away from stock original a lot. At least for some.
I'm using a different motor but this is how my belts lay out
closest to motor- crank and power steering
middle- crank, water pump, power steering, alternator
outside- crank, water pump, A/C
If I had space I could run the middle belt to the A/C as well but there is a rad hose in the way
Not sure but I would think you could get smaller width pullies.

 

There is a wide belt pulley Sanden compressor available for Flathead Ford V8's but it's only a single pulley. Maybe a wider belt like suggested by bmoran4? Have you tried contacting Vintage Air?

 

I for my own use would like to see how the a/c is mounted.

 

Simple solution: a lathe to machine a pulley / freshman class in high school.......

 

I had the same problem on my 40 Buick straight 8 and 52 f1 with early y block.The wide belt pulleys will never work with a narrow belt.Talked with an engineer from gates belts who told me the belt must have full contact with the pulley and ride flush with the outer rim of said pulley. I ended up cutting the crank pulley off the hub on both and buying and welding on a repro 64 Nova 283 crank pulley with the narrow belts. They can be had single or dual groove.No noises now.