My '82 Airstream 28 footer needed its smog pump (A.I.R.) replaced/hooked up so that I can get the MH smogged in Calif. Years ago, my late father (previous owner) had removed the pulley from the smog pump, since there are no smog inspections in Oregon. So my adventure started with trying to replace the smog pump pulley and belt.
I will make a long story short. First, it was an interesting experience in finding/getting all the necessary parts. Originally I thought that I could just replace the pulley and belt. It turned out that the pump was shot or more likely burned out. I eventually got most of the parts from Napa (not really my favorite parts house, but that's another story).
The best advice that I can give to anyone that is replacing a smog pump is to replace ALL related parts. One of the reasons for smog pump failure is that the exhaust check valves have failed and hot exhaust is fed back into the smog pump. If the check valves are shot, you will just burn up the smog pump from hot exhaust gases. After taking the old check values off, yes one of them was completely shot.
Smog pump ($90)
Air Control Value ($260) mounts directly to smog pump
Exhaust Check Valves (2 required) ($17 ea)
Smog Pump Pulley ($10)
Pulley bolts (3 required)
I'm reusing the hoses that connect the whole system together, but I did replace a few of the hose clamps.
The old pulley and bolts were missing so I had to hunt them down as well. You can easily buy the pulley, but the bolts were my biggest headache. No one knows what they are and it just happens that they are metric. Yes, metric! If fact the two mounting bolts for the smog pump are also metric, so get out those metric wrenches.
Do not mount the pulley on the pump before mounting the pump on the engine...you won't be able to get the large pump mounting bolts in with the pulley on. To R&R the pump, you need to have access from the top via the front of the dog house cover. You don't have to remove the dog house just the front top panel that the dog house hinge mounts to. Access is also required through the right side front wheel well. Jack up the front of the MH to get better access or remove the front tire. Always place a jack stand under the frame. Don't just rely on your front leveling jacks to hold the front end up. I had the leveling jacks deployed once and when I started the engine, the front jack released about 2 inches!
Liquid wrench or similar will be your best friend in removing the pump, check valves, etc. You do not want to twist the air tubes that mount to the exhaust manifolds.
With the smog pump pulley re-installed, I had to replace the belt with the correct belt. The Napa part# is 15495 for the Chevy P30 454 with A/C. This correct belt fits around the crank, water pump, alternator and smog pump.
I started the engine and all ran good. No belt squeeks! The only thing left to do is to attach a vacuum hose from the engine/carberator to the smog pump air control valve. If anyone knows or could look to see where this vacuum hose connects to the engine, I would really appreciated it!
Well, I'm now one step closer to getting the MH smogged.