Smog Pump Decoding.

[Nasblu]

When decoding a smog pump is there any numbers that link it to a specific model of car? I know the casting number and date on the rear cover and The Julian date on the side of the main case. And the various pulleys that are numbered? I have one stamped 008141S I am decoding this as the Jan 8, 1971? What does the 41 stand for? The rear case casting# is 7801149 what looks to be D59 casting date. With a 3927116AU Pulley. Is it possible for a early 1971 smog pump to have a April 5, 1969 casted case? The pump looks to never been apart. Just trying to learn more about smog pump numbers.

[cook_dw]

Going off of memory and I could be waaaaay off but this is what I get

008141S
0081 - 81st day
4 - 1974
1 - shift
S - without pressure relief valve

What color is the fan?

[the427king]

Too many numbers....81st day is 081 not 0081

[Nasblu]

The fan is Black. You think it was an error when originally stamped?

[cook_dw]

White fans were from 68-72ish. after that they were black. Please realize that I am going off of memory and my dates may not be 100% accurate.

[Kurt S]

http://www.camaros.org/emissions.shtml#pumps

[jl8z28]

Take the fan off and it will have a year on the front