Smog Pump on 68's?

[Dave K.]

Would a 68 have had the smog pump and related plumbing in the exhaust manifolds and such? If so anyone have any good pics of this set-up? 307 V8 by the way.

Thanks, Dave.

[cdowns]

I don't hink so as they were a few years later in mid to late 70's

[mike16]

dont know about trucks but I do know that A.I.R. systems were installed on cars in California since 66. Kinda rare if you can find them complete too.

[68Gold/white]

My 68 396 had an air pump on it, the under hood decal was still somewhat intact when I bought the pickup in 1980, not now though.
The air pump and associated parts were long gone when I bought it.
Not sure when and why air pumps wee installed on pickups...have not seen many pre 72's with them, though...

[WorkinLonghorn]

Don't know about your state and 1969 might have been different anyway but the 1/2 ton trucks in Calif. had pumps but the 3/4 ton did not have anything other than PVC.

[Dave K.]

Thanks guys, looks like mine had the stuff at one time. I found a 72 locally which has all of it so perhaps I'll grab it just to save it for the future...

['68OrangeSunshine]

Yes. California vehicles had the A.I.R. smog pump system for mdl.yr. 1968. My '68 C/10 Stepside with L6 292 had a smog pump and connecting lines into the cylinder head.
I have deleted the AIR stuff and used brass plugs to fill the AIR holes in the head. Truck was Fremont built, and originally sold in L.A.
I guess on the V8s, the AIR inputs were in the exhaust manifolds. I would advise you against re-installing an AIR system. They didn't do much for air quality in reality, and were a big performance drain, and also prone to manifold leaks. Mostly a political solution.
A well-tuned engine will pass emissions without the AIR installed. Most states don't even smog test vehicles this old. Arizona does, but they don't check to see if I still have obsolete gear under the hood.

[RedRoad]

My brothers all original 69 C20 with 350 had a smog pump. SPID showed CA emission so it was from the factory.

[davischevy]

My dad bought a 68 new here in Arkansas, and it had a smog pump.

He went back and traded for a new 69 and it did not have a smog pump.

[FirstOwner69]

Originally Posted by RedRoad

My brothers all original 69 C20 with 350 had a smog pump. SPID showed CA emission so it was from the factory.

Interesting. My 69 3/4 ton, built at Fremont and sold to me in southern California did not have any emissions other than a PVC as mentioned in WorkinLonghorn's post above. My take was, as he said, that the 1/2 tons had different emissions requirements than the 3/4 tons. I always figured the emissions were driven by the GVWR. Mine's also a 350.

In response to the OP's original question. The 68 service manual has a section (6T) devoted to the Air Injection Reactor. It shows both I6 and V8 applications but does not state when it was required.

[RedRoad]

Originally Posted by FirstOwner69

Interesting. My 69 3/4 ton, built at Fremont and sold to me in southern California did not have any emissions other than a PVC as mentioned in WorkinLonghorn's post above. My take was, as he said, that the 1/2 tons had different emissions requirements than the 3/4 tons. I always figured the emissions were driven by the GVWR. Mine's also a 350.

In response to the OP's original question. The 68 service manual has a section (6T) devoted to the Air Injection Reactor. It shows both I6 and V8 applications but does not state when it was required.

Does your SPID show emission line item?

[FirstOwner69]

Originally Posted by RedRoad

Does your SPID show emission line item?

No. The engine is original (stored in my garage now). The truck was made in Dec., 1968. I bought it at Barton's Chevrolet (now defunct) in Yorba Linda.

[Dave K.]

Here's why I was asking--I think the truck is a 71.

[RedRoad]

Originally Posted by FirstOwner69

No. The engine is original (stored in my garage now). The truck was made in Dec., 1968. I bought it at Barton's Chevrolet (now defunct) in Yorba Linda.

My brothers truck was purchased in Newhall, CA. Next time I go over Ill take a look at the door tag to see the production date and see what the dealer plate frame is.

[FirstOwner69]

Originally Posted by Dave K.

Here's why I was asking--I think the truck is a 71.

What in that picture makes you think 1971? The installation picture in the 1968 service manual looks just like that. Here's a link to a thread with links to the manuals. Look at section 6T.

http://67-72chevytrucks.com/vboard/s...d.php?t=558016

[FirstOwner69]

Originally Posted by RedRoad

My brothers truck was purchased in Newhall, CA. Next time I go over Ill take a look at the door tag to see the production date and see what the dealer plate frame is.

69s did not have door tags with production date info.

[RedRoad]

Originally Posted by FirstOwner69

69s did not have door tags with production date info.

Good to know, is there a way to figure out production month info?

[FirstOwner69]

Originally Posted by RedRoad

Good to know, is there a way to figure out production month info?

Not that I know of without the build sheet. The VIN would at least enable a comparison with mine and help estimate earlier or later production.

[mike16]

No air pumps in California cars in 66?Hmm?