A.I.R. Pumps

[Loren L.]

I'm chasing correct information on the A.I.R. setup for a '66 El Camino 396 with A/C. (Lucky me, a CA ElC! And it has to go on the car because it's an original engine and the last letter of the code changes for A.I.R.) The case of the pump that came WITH, but not ON, has the number 5696211 on it. There is also a circle marking with "65" in the center and a couple of others in the "cuts of the pie" sections of the circle. I'll be able to read those as soon as my electron microscope comes back from the lab.
In hopes that the General made the pumps fit as many cars as possible, I checked an Oct 67 & Oct 68 Chev/Corvette Pts Bks. No list of Chevelles, but both books show "5697255" for the 1966 Corvette, both SB & BB. My version of the JM calls out "7800308" for SB & BB.
Are the "56XXXXX"'s just castings for the case and NOT part #s?
Thanks

[Joe L.]

Re: A.I.R. Pumps

I'm chasing correct information on the A.I.R. setup for a '66 El Camino 396 with A/C. (Lucky me, a CA ElC! And it has to go on the car because it's an original engine and the last letter of the code changes for A.I.R.) The case of the pump that came WITH, but not ON, has the number 5696211 on it. There is also a circle marking with "65" in the center and a couple of others in the "cuts of the pie" sections of the circle. I'll be able to read those as soon as my electron microscope comes back from the lab.
In hopes that the General made the pumps fit as many cars as possible, I checked an Oct 67 & Oct 68 Chev/Corvette Pts Bks. No list of Chevelles, but both books show "5697255" for the 1966 Corvette, both SB & BB. My version of the JM calls out "7800308" for SB & BB.
Are the "56XXXXX"'s just castings for the case and NOT part #s?
Thanks

Loren-----


Any on-pump numbers that you find on an AIR pump will be casting numbers for that component of the assembly. They will not be a part number for the complete assembly. The part number for the complete assembly is, unfortunately, virtually never found on the pump assembly. In PRODUCTION, it was on the bins the pumps were supplied in and in SERVICE it's on the box the pump is supplied in. That's it.

The original AIR pump used for 1966 Chevelle with 396 (325 and 360 hp) was GM #5696468. Like I say, though, that number is virtually useless to you since it usually won't be found anywhere on the pump. This same pump was also used for many 1966 full size passenger cars with 4 barrel carbs and MANY other applications. It's very likely the pump you have is the correct one. My recollection is that this pump has one large nipple on the backing plate (for air intake) and one or two smaller nipples (for outlet air to manifolds). I just don't recall if there was one or two. The configuration of the inlets and outlets on the backing plate was the main way that 1966-67 pumps differed among applications---the rest of the unit was pretty much the same. If you have a good diagram available of the 66 396 AIR system, it will tell you if the pump should have had one or two outlet fittings on the back. Most 6 cylinder pumps have only 1 outlet, but some 66-67 8 cylinder applications also used 1 outlet from the pump if both manifold trees were fed from a "Y" connection. However, I believe that most 66-67 8 cylinder applications used the two outlet backing plate.

By the way, the 1966-67 Corvette AIR pumps were unique to Corvette applications. They used NO outlets off the backing plate; just the one large inlet nipple. The outlet bosses on the backing plate were either not machined or they were machined and were plugged with soft plugs. The outlets for the Corvette-only pumps were on a "T" that attached to the lower part of the aluminum pump case. So, it's easy to ID a Corvette-only pump.

[Mike M.]

Re: A.I.R. Pumps

66 and 67 corvette AIR pump backing plates wweren't machined. nor was it machined and pluigged with a soft plug. mike

[Joe L.]

Re: A.I.R. Pumps

66 and 67 corvette AIR pump backing plates wweren't machined. nor was it machined and pluigged with a soft plug. mike

Mike-----


As far as I know, only Corvette AIR pumps used the "T" off the main body of the pump for outlets. In any event, I have seen known-original 66-67 Corvette pumps that had the the rear plate outlet fittings machined for nipples, but plugged with soft plugs. I do not know if this configuration was common but I'm 100% certain that it was used. I've only seen 2 or 3 of these, but I'm certain that they were Corvette pumps. Perhaps I saw the only 2 or 3 that ever existed.

It is a possibility that these were originally SERVICE pumps rather than those used in PRODUCTION. However, the "fly in that ointment" is that I would not expect that too may SERVICE AIR pumps were ever installed on Corvettes during the time the GM piece was available in SERVICE. During that period, a VAST number of pumps CAME OFF, but few were installed for SERVICE replacement.

[Loren L.]

Re: A.I.R. Pumps

Loren-----


Any on-pump numbers that you find on an AIR pump will be casting numbers for that component of the assembly. They will not be a part number for the complete assembly. The part number for the complete assembly is, unfortunately, virtually never found on the pump assembly. In PRODUCTION, it was on the bins the pumps were supplied in and in SERVICE it's on the box the pump is supplied in. That's it.

The original AIR pump used for 1966 Chevelle with 396 (325 and 360 hp) was GM #5696468. Like I say, though, that number is virtually useless to you since it usually won't be found anywhere on the pump. This same pump was also used for many 1966 full size passenger cars with 4 barrel carbs and MANY other applications. It's very likely the pump you have is the correct one. My recollection is that this pump has one large nipple on the backing plate (for air intake) and one or two smaller nipples (for outlet air to manifolds). I just don't recall if there was one or two. The configuration of the inlets and outlets on the backing plate was the main way that 1966-67 pumps differed among applications---the rest of the unit was pretty much the same. If you have a good diagram available of the 66 396 AIR system, it will tell you if the pump should have had one or two outlet fittings on the back. Most 6 cylinder pumps have only 1 outlet, but some 66-67 8 cylinder applications also used 1 outlet from the pump if both manifold trees were fed from a "Y" connection. However, I believe that most 66-67 8 cylinder applications used the two outlet backing plate.

By the way, the 1966-67 Corvette AIR pumps were unique to Corvette applications. They used NO outlets off the backing plate; just the one large inlet nipple. The outlet bosses on the backing plate were either not machined or they were machined and were plugged with soft plugs. The outlets for the Corvette-only pumps were on a "T" that attached to the lower part of the aluminum pump case. So, it's easy to ID a Corvette-only pump.

Then how do you explain that the Oct 67 and the Oct 68 parts books list the 5696468 pumps as ONLY for 66-7 passenger cars?

[Joe L.]

Re: A.I.R. Pumps

Then how do you explain that the Oct 67 and the Oct 68 parts books list the 5696468 pumps as ONLY for 66-7 passenger cars?

Loren------


Simple. I expect that you are using a version of the P&A Catalog that does not include Chevelles, Chevy II, or Camaros. If it's a version which includes Corvette, then it's also a version which does not include the aforementioned models. The version which includes the aforementioned models also includes full size passenger. The version which includes Corvette also includes full size passenger and light trucks. So, full size passenger is common to both versions but it's the only model that's common to both versions. Just because a part is included in one of the versions for, say, full size passenger car does not mean that it's not included in the other version for other models.