[Joe37]

Looking for information about the metal cover over the bowl vent actuated by the accelerator pump. According to my Rochester Master information manual, the cover was not offered in '67, they started listing them in '68. This carb I'm working on didn't have one, it did come off an original low mileage car.

I see the covers on some '67 and others without. The service manual just has copies of the Rochester pictures, so no help there. This car is a non-A/C, 400 automatic, p/s. , no Ram Air or HO.

Also curious about the small bellows / boot over the accelerator pump rod that keeps dirt out, was that ever a standard piece?

Joe Hand

[unruhjonny]

Originally Posted by Joe37

Looking for information about the metal cover over the bowl vent actuated by the accelerator pump. ...

As I have understood it, this was not used on 1967 Pontiac Quadrajets.
I believe it was also absent on Chevrolet Quadrajets for other years (I am thinking they were present for 1970, but not 1969 or 1968) - so it was not a standard piece, but rather it's an item that often appears to be added by people "restoring" these carbs.

Originally Posted by Joe37

Also curious about the small bellows / boot over the accelerator pump rod that keeps dirt out, was that ever a standard piece?

Joe Hand

As I have understood, it was only a part used on 1968.5-1972 RAII/RAIII/RAIV, and 455HO application Qadrajets.
These first showed up (again, as I have understood it) on the 7028270/7028273 Quadrajets - but my gut says they were absent from the earliest units.

In essence, the airhorn needs to have been finish machined to accept the retaining lock washer - other airhorns didn't have this feature (this is from my personal observations).

[gto4ben]

According to the Firebird Rochester carburetor chart section and the Delco Carburetor Bulletin 9C-6001, idle vent shield 7035431 was first used on '68 quadrajets. The part was not listed on the '67s.

[Joe37]

That's just what the Rochester manual shows, just one less part I have to trck down. Thanks for the information,

Joe

[65 Lamnas]

It’s difficult to use the terms “always” and “never” when it comes to this stuff.

The 7028270 pictured is an NOS carb as far as I can tell. Not certain the story on it.

But it has the dust boot feature, plastic fast idle cam, vent cover and pick code. I haven’t seen many of these carbs and am not sure why the cam is green. Seems most Pontiacs were brown or tan.

[242177P]

Originally Posted by 65 Lamnas

It’s difficult to use the terms “always” and “never” when it comes to this stuff.

The 7028270 pictured is an NOS carb as far as I can tell.

Except NOS is hardly representative of what rolled
off the assembly line. Some of those are parts that
were made during the initial run. While other stuff
is merely service replacement parts. The difference
between the two can be massive. Explains why the
fast idle cam is the wrong color.

[Kenth]

I have found that the color of the fast idle cam changes from light green to tan/yellow after a some decades usage and thousands heat cycles, sitting right above the intake crossover channel.
Much like the silver-blue engine color changes to a greenish hue.

[60sstuff]

Originally Posted by Kenth

Much like the silver-blue engine color changes to a greenish hue.

Back in the day (70’s 80’s) you could purchase that factory correct greenish hue.

Love this color that started in 1966.
Not thrilled with that silver stuff.

[Kenth]

Yes, 1966-70 silver-blue metallic is one of the nicest, if not THE nicest, engine color when newly painted.
Unfortunately after some decades of using these cars this color turns greenish.

[Longs]

My '67 was built in June 1967 at the Pontiac plant, 335 HP automatic with air conditioning, original 7027262 Rochester Q-Jet. No cover over the bowl vent, no rubber boot on the accelerator pump shaft.