Hello Again;
Well...I was going to remove my AIR System...but decided to possibly put it back together. Now I'm "stonewalled" because no one can determine the correct belt (the belt was missing when I bought it). NAPA say's that I need the "fan to pump" belt (Gates 7315, which they no longer stock). As I gaze wistfully into my engine department...the only pullies that line up are "crank to power steering to air pump" The "fan to pump" do not line up. "Crank to pump" will not work because of the fan. So.... all you motor heads out there...I need a "block of instruction" please... What do I do?
Thanks again
Fat Freddie

Look at some older model years for the belt. It may list it that way. The engine is the same, and the pullies the same for many years. If that fails or you want a rough guess, use a 3/8 rope and wrap it around the pullies and get a length measurement. This may be right on, or just a good starting point. You may need to go up or down an inch or two.

Ken Styer

Scratch, are you missing a pulley on the water pump. I believe there should be 3 grooves, the AIR belt having it's own pulley to the very front. I remember removing the one pulley when I removed my smog stuff on my 79. That's probably why it looks like it lines up with the power steering and crank. It should be the front belt of 3 on the water pump directly to the AIR pump. I can check for both a pulley part no. and a belt length or no. if you like. Mike

Thank you Mike for your "reply". If it wouldn't be too much trouble, I would appreciate the help with belt and pully number. But you know...looking at my set-up... it doesn't look like the pully has been replaced. The 2-belt pully on there looks the same age as everything else. And why...would a person go through all the trouble of changing out the pully...and leave everything else. The only thing missing is the belt (and/or pully). If I install an additional pully, will that effect the length of the fan shaft and fan? Frumphhh... Mebbe I'll just find someone with a portable welder (I was in the middle of changing out the plugs and wires when I decided to do something with the AIR system)...get a dremmil tool and cut/weld the tubes shut and strip the rest.
Thanks again
Fred

There were many samll block chevys with a power steering belt that did not go around the fan pulley. Just the crank and power steering pump. Look at AutoZone and have the counter man print belt diagrams of several different chevys, Caprice, Nova etc. Go up or down several model years. Look at 283, 327, 350, 400, any of these combinations may, or may not, work. It will take some research, but can be found. NAPA or someone might have a belt routing book, with printed pictures. Much easier.

Ken Styer

Thank you Ken for the reply. If I can't get this sorted out, I may have to do the "3/8" rope thing. I was hoping that someone out there would be able to look at their "81" and say "this is what it is". Mike may be correct with his assumptions about the "pully". In which case... I'll have to do some changing around. Good thing I'm not in too much of a hurry to get her back on the road. Well...not too much anyway.
Thanks again
Fred

Thats the way it is now Ken...power steering to crank. But when you "sight" the pullies...air pump. crank and power steering match. But you can't use air pump to crank, or air pump to power steering because of the fan mount. it has to go around the crank. Right now I have:
crank to power steering (new belt)
crank to fan to alternator
fan to air con
one empty pully on crank
I'm getting confused

Scratch, the AIR pulley is a seperate single pulley that stacks on top of the existing pulley. It's just a single add on pulley. It will line up with the power steering pump pulley but the AIR belt DOES NOT go to the crank or PS pump. It goes direct - AIR pulley to 3rd water pump pulley that you are probably missing. I will get the part no and belt length by this evening. Have to look through some newspaper wrapped parts in the shop. Mike

Scratch, manual shows: first belt from motor- alternater, water pump, crank. Second belt- AC, water pump, crank. There would be 2 "third" belts-one of them goes crank to power steering pump. Other "third" belt goes AIR pump to water pump. These two belts line up together. Mike

OK Scratch, I'm back. The pulley for the AIR pump that goes on the water pump is a 6" X 1 1/8" neg offset pulley, GM p.n. 3991425BX. The belt is GM p.n. 9433616. It is a .380X33 Dayco belt. Very small, about the size of a dinner plate. If the previous owner ever changed the water pump or fan clutch, I wouldn't be surprised if he left the pulley off if he wasn't using the AIR system. You say the AC goes only to the water pump. I think that belt is wrong and should go to the crank also, you say you have an empty groove. Does it line up with the AC? Mike