Smog Pump Date Code

[John F.]

I have a Smog Pump with date code stamped into the side

00511S

Can anyone help me decipher it?

[Joe L.]

Re: Smog Pump Date Code

I have a Smog Pump with date code stamped into the side

00511S

Can anyone help me decipher it?

John-----


It decodes to the 5th day (005) of 1971 (1) (or, possibly, 1981). The plant identifier code is the second "1". The "S" is the pump model. Virtually all, if not all, 1968-75 Corvette AIR pumps were model "S". These were also used on most other GM cars of the period.

[John F.]

Re: Smog Pump Date Code

Thanks Joe. You're the best!

[Loren L.]

Re: Smog Pump Date Code

Are we sure that the second "1" designates a "assembly plant" and not a "shift" designation, such as on T-10 Transmissions? I also have a pump on hand that is stamped "30251A" that I was told =s 302nd day of 1965, lst shift and that A =s an assembly plant (although my source could NOT
ID what "A" meant). Why would you need a "model" designator when you already have a part # that designates what model it is?
Clarification?

[Joe L.]

Re: Smog Pump Date Code

Are we sure that the second "1" designates a "assembly plant" and not a "shift" designation, such as on T-10 Transmissions? I also have a pump on hand that is stamped "30251A" that I was told =s 302nd day of 1965, lst shift and that A =s an assembly plant (although my source could NOT
ID what "A" meant). Why would you need a "model" designator when you already have a part # that designates what model it is?
Clarification?

Loren------

Who has the pump part number? It's nowhere to be found on any of these pumps.

As far as the second "1" is concerned, it's always been my understanding this represents the plant code. Could it actually represent the shift? Yes, I suppose it could. However, either way it's rather academic and a moot point as far as I'm concerned. I might add that I've never seen anything but a "1", so if it represents a shift, then every pump I've seen was manufactured on the shift represented by "1". Seems unlikely since by 1968, these pumps were being used on just about all GM cars and trucks and they must have been making them by the millions.

All of the 1966-67 pumps I've seen have an "A" suffix code. As far as I know, this is the pump model. The 1966-67 AIR pumps were of a different model than the 1968 and later pumps. As far as I know, the "S" represents the pump model. Could it actually represent a plant code? I suppose it could but, once again, it's a rather moot point. I've never seen a 1968-79 pump with other than an "S" suffix code.

[John F.]

Re: Smog Pump Date Code

What's a mint pump like this go for? I'm selling for my father.
2 Check Valves 5361992
Diverter Valve (GL)
Diverter Valve Extension 3942533
Hose Set
1 3932476 GM RC KV
1 3947740
1 Vacuum Hose with White Strip
4 Tower Clamps Dated 4 70
1 T Style Wire Tie

Pulley 3917234
Orange Mgt Bracket 3923214
Pump 00511S
Rear pump Cover 7801149 D51

[John F.]

Re: Smog Pump Date Code

here is a pic. thanks fellas!

HNY!

IMG_4156.jpg

[Loren L.]

Re: Smog Pump Date Code

Joe, you're going to force me out into the garage to try and physically put my hands on the two pumps - I took the info from a paper listing. But I'm still glad that I asked, because it seems to me that you've now gone from an absolute declaration of what the codes mean to something less than that. "1" as a "shift" could still mean that, even if GM never ran 3 shifts. Unfortunately my source's name is now preceded by the phrase "the late", so I cannot get further clarification from him. I'll try and find the pumps.

[Joe L.]

Re: Smog Pump Date Code

Joe, you're going to force me out into the garage to try and physically put my hands on the two pumps - I took the info from a paper listing. But I'm still glad that I asked, because it seems to me that you've now gone from an absolute declaration of what the codes mean to something less than that. "1" as a "shift" could still mean that, even if GM never ran 3 shifts. Unfortunately my source's name is now preceded by the phrase "the late", so I cannot get further clarification from him. I'll try and find the pumps.

Loren------

I did not make any "absolute declaration" of what the codes denote. I expressed my belief of what they denote. I don't always prefix my comments with the qualifier "I believe...". However, whether I state it or not, it's to be considered there.

[Loren L.]

Re: Smog Pump Date Code

In any case, I found the 2 pumps - no small degree of luck there. The first carries an assembly stamping of 30251A; the case does carry a number of 5696211 and a stylized "S" in a box - Saginaw? - but rather than a number for the pump, it seems more likely that it the case's part number; the "cover" has a casting #5696132 and 2 separate casting marks of "D5" and "172"; I would speculate that indicates something about when the cover was cast, but I can't squeeze the 172nd day into April (D), no matter how hard I try. I BELIEVE that the source of this pump is my 66 ElC, 396, auto, A/C, PB, PS.
The 2nd pump is assembled 07671S with NO markings on the case except "DO NOT CLAMP IN VICE" - yes, vice (SIC) - and the cover is cast as
7817872.

[Joe L.]

Re: Smog Pump Date Code

In any case, I found the 2 pumps - no small degree of luck there. The first carries an assembly stamping of 30251A; the case does carry a number of 5696211 and a stylized "S" in a box - Saginaw? - but rather than a number for the pump, it seems more likely that it the case's part number; the "cover" has a casting #5696132 and 2 separate casting marks of "D5" and "172"; I would speculate that indicates something about when the cover was cast, but I can't squeeze the 172nd day into April (D), no matter how hard I try. I BELIEVE that the source of this pump is my 66 ElC, 396, auto, A/C, PB, PS.
The 2nd pump is assembled 07671S with NO markings on the case except "DO NOT CLAMP IN VICE" - yes, vice (SIC) - and the cover is cast as
7817872.

Loren-------

Yes, the 5696211 and 5696132 are casting numbers for the body and rear plate of the pump. They are not part numbers for the pump assembly. The stylized "S" does represent Saginaw, the GM division that manufactured the pumps. You will note this is the same stylized "S" as seen on 63-82 Corvette steering gear assemblies, also manufactured by Saginaw. This is a 1966-67 style pump.

The "D5" denotes Danville, IL foundry and pattern #5. 172 may be the julian date code of the casting without reference to year. Danville did this commonly.

The 2nd pump is a C3 era pump manufactured on the 76th day of 1967 or 1977. March, 1967 seems too early for a C3 pump but it's possible some were made this early. With a photo of the pump I might be better able to ID it.