[Hotrodjohn71]

I have a Rochester 2GC carburetor on my 1965 Pontiac engine.
This type of 2GC requires a check ball approximately .156" in diameter to go in a recessed check ball hole in the bottom of the accelerator pump well.
All of the research I have done regarding the check ball (that is in the accelerator pump well) says that the ball should be made out of aluminum.
The aluminum is lighter and allows the fuel to enter the pump well easier than a stainless steel ball.
The kit that I got appears to have a stainless steel ball for the pump well as it is magnetic. I am wondering if this ball is meant to be stainless steel in some models and aluminum in others?
I do know that these carburetors can have two or even three check balls. I have the other check balls in their appropriate positions in the carburetor. I am only specifically asking about this check ball for the accelerator pump well.
There is actually a carburetor shop nearby where I can get the aluminum ball, but I'm wondering if since the kit I got has stainless steel if anyone else has experienced this also.

[mgarblik]

That year 2-Jet uses 2 check balls. They are clearly different diameters. The small one is the inlet check ball for the accelerator pump as you mentioned and goes in the pump well. All the ones I have worked with have been aluminum. It is extremely important that the SMALL check ball go in that location. The big one will go in there and get stuck and can be very difficult to remove. The large check ball goes in the outlet check first followed by a small light gauge spring and a T-pin sheet metal retainer to hold the whole thing together. They are made of steel in all the kits I have. I don't know if a correct size steel ball would be an issue or not. I have several aluminum ones here and can send you one if you need it. PM me if you want me to mail you one.

[Hotrodjohn71]

Thank you for the reply and the offer but that wont be necessary. We have a carburetor repair shop nearby that has the aluminum small balls that I can get on Monday, but I just wanted to see if anyone had the steel one like I have.
It came in a kit from Tomco, 5114A from Carburetors Unlimited.
I havent found anywhere anyone talking about steel so it might be a fluke.

[Kenth]

Rochester uses the #7002120 aluminium pump inlet check ball for 2G´s.

Some 2G´s, e.g. most Chevy applications don´t use this check ball, instead these uses an extended slot letting the fuel into the bore.

Aftermarket kits can contain all sorts of odd stuff, like steel balls instead of alu and goofy inlet valves.

[carbking]

I really dislike the words "every" or "always"; but to date, every Rochester 2G for which we have produced a kit uses the 7002120 aluminum ball in the pump well if a ball was used.

As Kenth mentioned, some applications use a slotted pump well instead of a ball.

A more serious concern in the Tomco kit than the incorrect ball, is the wafer fuel valve they used to use. Hopefully, by now these have been eliminated.

Jon

[Hotrodjohn71]

Thank you fellas. Greatly appreciated.