Rebuilding an A.I.R. (Smog) Pump

[rsd9699]

Hi All,

I have looked on the net for a series of pictures on how to rebuild your smog pump. I have have found a few pictures where the end was removed showing the internal parts but not a exploded view of the unit or any instructions to how to do it beyond just looking.

I have one that is good shape but the grease is dried out after 40 years. I have removed the end and it is fairly simple device and requires removing (pulling out) a plate that is pressed into the drum to get the parts out.

What concerns me is the drive end. Once you remove the pulley and fan (filter) you can clean things around the hub. There appears to be two plastic screws or rods once things are clean that are 180 degrees apart from each other. Before I make a mistake and press the hub and drum assembly out of the aluminum housing, I have a few questions.

Is the hub threaded onto stub shaft with left hand threads?
What are the plastic screws or rods attached to?
Will the hub press thought the hole there the bearing fits (it looks rather tight)?

Any real life experiences, photos, or exploded diagrams available?

Thanks
Ron

[Dave@Moon]

I'm sure your questions would vary depending on which manufacturer you're talking about. If you are rebuilding an air pump from a GM vehicle they published a "Component Manual" for each model year where rebuild procedures are listed for almost all components. These air pumps I'm nearly certain are included. I believe other brands had similar published works, or else the suppliers did.

[rocketraider]

Ron, teardown/rebuild procedures should be in the factory-issued chassis service manual for your car.

Makes me glad Oldsmobile rarely used them. One less thing to have to worry with restoring and keeping operable.

My dad bought a 1968 ElCamino new. 307 2-bbl, 3-speed, and a smog pump. One of the injection manifold check valves failed and allowed exhaust gas back into the pump and locked it up. That burning plastic was a smell I will never forget. And naturally it did it while I had the truck running errands for him, so I got blamed for a mechanical failure I had absolutely no control over and that had probably been building for some time.

[rsd9699]

Yikes!

I did forget the car info!

1973 Cadillac engine - the pump fits 1969 through 1974.

I do not have pictures of mine just yet but using one supplied that shows the major parts. I marked with an arrow, did you press this part out of the housing to lube the bearing that is behind the hub (the plastic fan comes off easily and I need to get a replacement for mine)?

Your diverter valve mounts on the rear of your pump and on the side of my pump. What did you do to clean the aluminum housing so nicely. I have used lots of elbow grease on mine and it needs a little more to match yours?

There are five needle bearings that I can see on mine and I am guessing that the front bearing is a standard 203 double sealed ball bearing. The vane bearings are small and ride on the shaft of the rear cast iron housing that is hidden in this picture. Then a large needle bearing for the rear of the vane drum that the race is pressed onto the rear housing.

Since Cadillac offered no service parts for the pump proper, I doubt that the service manual discusses it at all. The 1980 Cadillac manual that I do have does not tell you anything other than remove and replace procedures.

I had a Father-in-law that had a truck. He NEVER did anything to the truck service wise. Nearly every time I used it - something broke. Or it broke with him after I had used it and I got to fix it and receive the blame. I got smarted and did not borrow his truck. It still broke and I still fixed it for him but I got to point to him and say "You busted it royally this time!". Ha Ha - great when the worm turns!

Thanks
Ron

[rsd9699]

Once again - many thanks for the comments!

I took a bunch of pictures of the primary parts that I have disassembled and fairly clean. I will take more and post them when I get to the reassembly stage.

I would like to see a picture of the puller you used to pull the hub with, I may need to get one like it to do my task at hand.

What kind of hi-temp paint are you in reference to? I see the black on the end part and I will paint mine black as well. It was originally black after I got most of the gunk off.

On the casing, is that clear coated? Do they make a hi-temp clear?

Here a a few pictures with my trusty screw driver pointing out things of interest to me.

Maybe your helper can help you take some more picture? At that age, I guess that with the holidazy at hand, it must be tough to stay focused (great age to be five and it be December!).

I wonder if the vane shaft is pressed into the cast iron end tightly?
I think I have to pull the retainer that the rear bearing is pressed into to remove the vanes inside of the drum?
What are the plastic parts going to on the front?
Is there a vacuum diaphragm in the diverter valve or a piston? Mine moves but does not hold vacuum making me think it is a piston.


Enjoy!

Ron

[rsd9699]

If you look at the front of my pump, would the legs of the puller you have used, fit under the hub and between the pump housing?

Cadillac injection is via the passages made into the head. I am planning on complete functionality just to make your government happy.

I will check the auto parts store for the clear satin hi-temp paint. I am sure I have seen it but never really gave it a second thought. But with aluminum, you got to do something with it or it will dull, pit and attracts all kinds of junk in a hurry.

I have been thinking of getting a small blaster. But I figure if I do, then I will use it and have to get a bigger one and then a bigger one....

I am not far from any parts places but the Dallas traffic makes a 15 minute run turn into a 3 hour hassle.

Thanks for the tips!

Have a good holiday!!!!!!!!!!!!!!!!!!

Ron