The Stovebolt Site Forums The Shop Area Engine Shop rochester rebuild review

Soooooooo....
Here's the thing. It's almost winter, and up in Vermont it's a little too cold for me to do any kind of outdoor bodywork stuff on my 1959 Apache (it lives outdoors for lack of a garage), and the engine is waiting a few weeks until a space opens up in my buddy's shop to be rebuilt, so I'm busy cleaning up and painting engine parts and such, and rebuilding the carb.
I have a few questions about the carb.
First of all, I don't know if its the stock carb or not....I have no reason to believe it's not, it's a Rochester B, you know, 1 barrel, man. choke, 10 parts...
First of all, the guys at the parts store couldn't match the number for the rebuild kit, and in the carb section in my old chilton's book, the number is skipped over. The number is 7004497 ummm...I think, I don't have it on hand, but I'm pretty sure that's it...maybe it's 7740097....but whatever it is, it ends with 97, and all the books only go up to 95, then skip up a bunch. The kit I wound up getting seemed to match all the parts, so I guess it's not a big deal. Anybody have any insights????
Next, and this is the big one...all the exploded diagrams I have show a spring holding a ball against the hole in the main well support assembly where the power piston runs into it, and it makes sense that there would be, but there wasn't a spring or a ball whan I cracked mine open. Should there be? It looks like it was rebuilt not too long ago, so maybe somebody forgot to put it in? Or is my carb a unique wierd design that just doesn't have this? There are a few different little balls and springs in the rebuild kit, and I put a ball and spring that seemed to fit nicely in , and they they push up pretty easily, so I don't know....
Any help would be great....I didn't tighten the screws too much yet, and it wan't be needed at least until the engine is built...but I'd love to solve this soon!
Any other advice on a first attempt at a carb rebuild?
Thanks, guys
vtapache

vtapache,

I'm looking at the diagram in the '59 Parts manual and it does show (from the top down), a ball, a spring, and a screw under the hole in the main jet and power valve support. The grouping of the ball, the spring and the screw is listed as the 'valve unit, carburetor power '

It appears that there are two holes in the bottom of the support. The smaller one holds the metering rod jet. The larger one holds the ball, the spring and a screw/jet. Can't tell from the diagram if the 'screw' has a hole in it or not.

The parts manual lists carb repair kits for 57-59 Ser. 3-4-6 (6 cyl.):

use w/carb. 7003526-3863-64-65-3968-4468-4475-76-77-78-4495-4620-4915-5140-5921-22-5982-
7172-7180-81-9253-54-55-7013029-3953

Which I think translates into the following carb numbers being used on 6 cylinder trucks from 57-59:

7003526, 7003863, 7003864, 7003865, 7003968, 7004468, 7004475, 7004476, 7004478,
7004495, 7004620, 7004915, 7005140, 7005921, 7005922, 7005982, 7007172, 7007180,
7007181, 7009253, 7009254, 7009255, 7013029, 7013953.

Don't worry about having the right kit, the same one is good for about 30 years, the only difference being the accelerator pump. Iirc, you should have the ball and spring in your B model.

vtapache,

The only other spring/ball combination in the carburetor is the accelerator pump discharge check valve.

The '61 service manual says to "drop the large ball into the pump discharge cavity of the bowl and then place the bronze colored spring on top of the ball. Index end of pump discharge guide into bronze spring and press down until guide is flush with bowl surface."

Got to agree. Rebuilt my Roch on my 261 thinking that it might have come from a 235 or from so other car. Bought two kits. One for a truck and one for a car. The truck one was right and even between the two kits there was very little difference. The number on my carb base wasn't found in the cross reference guide but the kit worked great.

If your carburetor is the same as mine, you will have two ball and spring pairs and they are different sizes. The one set is for the pump and without it the pump will not work. the other is inside the assembly which holds the power valve in place. This ball valve is pushed down off it's seat by the power piston under certain vacuum contions to allow greater fuel flow for more power, hence "power valve".

thanks guys, that helped a lot!
vtapache