Yellow marking on smog pump

[hihorse]

There is a yellow paint mark on this survivor smog pump assembly, do you think it is a factory mark?
Also the pump (dated 20081Y) has a relief valve and all the clamps are dated 1 69, no wire on diverter(29297), is this original for an early car?

[KurtS]

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

No 69 Camaro pump had that relief valve installed.

[Jerry@CHP]

I doubt that paint daub is an original factory marking.

Jerry

[hihorse]

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

No 69 Camaro pump had that relief valve installed.

Would some early cars have the valve as the 1969 Camaro AIM shows a relief valve for L78, page 311, 312.

[Steve Shauger]

I have looked at many cars both big block and small block built first week of production of 69 and none have had the relief valve.

[hihorse]

Which Chev model would this setup belong to?

[Jerry@CHP]

Solid lifter cars in 1968.  Z28 and L78.

Jerry

[hihorse]

although the date on the pump reads July 18,1968, and could be originally on a very late 1968 Camaro, my guess would be more likely the complete setup pictured (pulley is 458DA) was on a early 1969 model year.

[KurtS]

although the date on the pump reads July 18,1968, and could be originally on a very late 1968 Camaro, my guess would be more likely the complete setup pictured (pulley is 458DA) was on a early 1969 model year.

Well if you disregard what Jerry, Steve, and I say, you could assume that.
I think that all 3 of us will still say that pump was not used in 69.

Additionally, the fact that there's extra markings that are not factory on it suggests the pump is not in its original configuration.

[hihorse]

You may be correct about the configuration.  Nobody has offered an understanding on the discrepancy in the 1969  Camaro AIM. The 1969 Corvette AIM pictures the relief valve for the L71 and in Dobbins book the 1969 L71 and L88 has the relief valve pictured. So in 1969 Chevy used the relief valve on some solid lifter cars but not on the solid lifter Camaros. I wonder why?

[KurtS]

Nobody has offered an understanding on the discrepancy in the 1969  Camaro AIM.

Cause the 69 AIM was based on the 68 AIM and not all drawings were redrawn completely. The 68 dash is still shown too.....

[hihorse]

I could be wrong but the drawings on page 311 and 312 of the 1969 Camaro AIM appear to have been redrawn as they have the different configuration from the 1968 L78.

[JohnZ]

I could be wrong but the drawings on page 311 and 312 of the 1969 Camaro AIM appear to have been redrawn as they have the different configuration from the 1968 L78.

The A.I.R. pump isn't the subject of those pages - it's just background. All 1968 applications that used the relief valve on the A.I.R. pump (L35, L78, Z28, etc.) show the valve separately as an assembly plant-installed item; in 1969, no relief valve was used, and it's not called out in the 1969 A.I.M. for installation for any application. Those pages were re-drawn (rather than carrying over the illustrations from '68) due to the completely new 1969 accessory drive system which relocated the alternator and A.I.R. pump from their previous 1968 locations.

If you look in L78, sheet A2, under 6T (which is the A.I.R. pump), it says "assembles same as RPO L35; if you go to L35, sheet A2, under 6T, it says "assembles same as production". If you go to UPC 6, sheet A6 (the production A.I.R. pump installation), there's no callout for installation of the relief valve, as none was used in '69 (although the background illustration shows it on the pump). Some component illustrations are more accurate than others - depends which illustrator drew it; their focus was installation and fasteners, not detail appearance of the part.

Observation of hundreds of known-original cars has confirmed that the relief valve wasn't used in 1969 (although it's present on some Service replacement pumps, which cover a number of different applications).

[hihorse]

Thanks, excellent analysis

[69 Z11]

Well if you disregard what Jerry, Steve, and I say, you could assume that.

Now that's funny, I don't care who you are.