Identify Rochester 2 barrels

racinrod67 · November 16, 2006, 08:12:09 PM

What did this carb come from and what size is it? Casting # on the fuel bowl is 7009094. Atomizer/nozzle # is 7098. The top of the carb has a vent that is actuated by the linkage. Label on the top reads"GM RP 2 Jet Rochester"

enjenjo · November 17, 2006, 10:17:00 AM

what does the bolt pattern on the base measure? It sounds like a 2G, or 2GC. Typically used on 283 or 307. about 300 cfm, though Rocester never rated them that way. There should be a tag on one of the float bowl screws, that would identify it for sure.

Arnold · November 17, 2006, 09:47:43 PM

Quote from: "racinrod67"What did this carb come from and what size is it? Casting # on the fuel bowl is 7009094. Atomizer/nozzle # is 7098. The top of the carb has a vent that is actuated by the linkage. Label on the top reads"GM RP 2 Jet Rochester"

The numbers that are CAST #'s on Rochesters,and their parts are really pretty meaningless. I know of NO cross reference/part relation..NOTHING at all to do with those. Oft. wish I had had some info! There must be something,someone.. somewhere that knows about them? Some authority/expert. These are the casting #'s. They are not part #'s Numbers that are actually cast. Raised numbers. I have gone on wild goose chases for those before.They often get confused with the numbers that are stamped on the actual parts,castings.
PART numbers that are stamped are a whole other story. There should be a number stamped into the float bowl somewhere. Probablly vertically.
As has been mentioned..there should be a metal tag with a number on it. These are often so rusted that the #'s..some of them are really impossible to decipher.It is also very nice..haha..when rebuilders don't use the same tag..or one of their own..or a service package or a reman. unit.
The number you gave us here sounds to me like a casting number.? Rochester casting numbers..especially air horns seem to have casting #'s that length with the 0's and are not of even the newer..02/or 04 series of carbs.I could be wrong..but I can check it out for you..or another # Probablly a circular type # cast somewhere. There IS some sort of a code to break these numbers down to a certain point. But that is it. I don't even know where that info is?

I do have a Rochester line manual(9C)...AND the master carb # cross reference from about 1940-1987..that can take me right from a carb.number to a sheet in the manual listing ALL the parts,#'s,Most of the jet/rod.hanger sizes,pictures,applications,years,models,transmissions,engines,kits,updates associated with that # for most carb.s, vehicles. I can help anyone out with that information! I can also go backwards with it to some degree and come very close to finding what carb #/parts,jets,rods etc, should go..or can be built for a specific model/engine.This is not right here..I will be where that info is in a couple of days if you can wait.

reborn55 · November 17, 2006, 11:18:55 PM

I have looked at numerous Rochester sites and could not find that number but numbers in that sequence appear to be from the late 50's

Arnold · November 18, 2006, 11:02:16 AM

Quote from: "Arnold"
Quote from: "racinrod67"What did this carb come from and what size is it? Casting # on the fuel bowl is 7009094. Atomizer/nozzle # is 7098. The top of the carb has a vent that is actuated by the linkage. Label on the top reads"GM RP 2 Jet Rochester"

The numbers that are CAST #'s on Rochesters,and their parts are really pretty meaningless. I know of NO cross reference/part relation..NOTHING at all to do with those. Oft. wish I had had some info! There must be something,someone.. somewhere that knows about them? Some authority/expert. These are the casting #'s. They are not part #'s Numbers that are actually cast. Raised numbers. I have gone on wild goose chases for those before.They often get confused with the numbers that are stamped on the actual parts,castings.
PART numbers that are stamped are a whole other story. There should be a number stamped into the float bowl somewhere. Probablly vertically.
As has been mentioned..there should be a metal tag with a number on it. These are often so rusted that the #'s..some of them are really impossible to decipher.It is also very nice..haha..when rebuilders don't use the same tag..or one of their own..or a service package or a reman. unit.
The number you gave us here sounds to me like a casting number.? Rochester casting numbers..especially air horns seem to have casting #'s that length with the 0's and are not of even the newer..02/or 04 series of carbs.I could be wrong..but I can check it out for you..or another # Probablly a circular type # cast somewhere. There IS some sort of a code to break these numbers down to a certain point. But that is it. I don't even know where that info is?

I do have a Rochester line manual(9C)...AND the master carb # cross reference from about 1940-1987..that can take me right from a carb.number to a sheet in the manual listing ALL the parts,#'s,Most of the jet/rod.hanger sizes,pictures,applications,years,models,transmissions,engines,kits,updates associated with that # for most carb.s, vehicles. I can help anyone out with that information! I can also go backwards with it to some degree and come very close to finding what carb #/parts,jets,rods etc, should go..or can be built for a specific model/engine.This is not right here..I will be where that info is in a couple of days if you can wait.

I just did a Google for ya..someone says they are centre tri-power J2,Ponch.. from around 1957/8/9 floatbowl castings #'s.If they are casting #'s then I dunno where we can go with that?
I will take a look in my info either today or tomorrow

Arnold · November 18, 2006, 04:39:52 PM

Quote from: "Arnold"
Quote from: "Arnold"
Quote from: "racinrod67"What did this carb come from and what size is it? Casting # on the fuel bowl is 7009094. Atomizer/nozzle # is 7098. The top of the carb has a vent that is actuated by the linkage. Label on the top reads"GM RP 2 Jet Rochester"

The numbers that are CAST #'s on Rochesters,and their parts are really pretty meaningless. I know of NO cross reference/part relation..NOTHING at all to do with those. Oft. wish I had had some info! There must be something,someone.. somewhere that knows about them? Some authority/expert. These are the casting #'s. They are not part #'s Numbers that are actually cast. Raised numbers. I have gone on wild goose chases for those before.They often get confused with the numbers that are stamped on the actual parts,castings.
PART numbers that are stamped are a whole other story. There should be a number stamped into the float bowl somewhere. Probablly vertically.
As has been mentioned..there should be a metal tag with a number on it. These are often so rusted that the #'s..some of them are really impossible to decipher.It is also very nice..haha..when rebuilders don't use the same tag..or one of their own..or a service package or a reman. unit.
The number you gave us here sounds to me like a casting number.? Rochester casting numbers..especially air horns seem to have casting #'s that length with the 0's and are not of even the newer..02/or 04 series of carbs.I could be wrong..but I can check it out for you..or another # Probablly a circular type # cast somewhere. There IS some sort of a code to break these numbers down to a certain point. But that is it. I don't even know where that info is?

I do have a Rochester line manual(9C)...AND the master carb # cross reference from about 1940-1987..that can take me right from a carb.number to a sheet in the manual listing ALL the parts,#'s,Most of the jet/rod.hanger sizes,pictures,applications,years,models,transmissions,engines,kits,updates associated with that # for most carb.s, vehicles. I can help anyone out with that information! I can also go backwards with it to some degree and come very close to finding what carb #/parts,jets,rods etc, should go..or can be built for a specific model/engine.This is not right here..I will be where that info is in a couple of days if you can wait.

I just did a Google for ya..someone says they are centre tri-power J2,Ponch.. from around 1957/8/9 floatbowl castings #'s.If they are casting #'s then I dunno where we can go with that?
I will take a look in my info either today or tomorrow

I just looked for ya..and there is nothing on that #

racinrod67 · November 23, 2006, 09:55:18 AM

Quote from: "enjenjo"what does the bolt pattern on the base measure? It sounds like a 2G, or 2GC. Typically used on 283 or 307. about 300 cfm, though Rocester never rated them that way. There should be a tag on one of the float bowl screws, that would identify it for sure.

Bolt pattern is 1 7/8" x 3 1/4". Butterfly diameter is 1 7/16". No tags left on any of the four carbs. They are mounted on a Man-A-Fre intake. Trying to determine if they are period correct, what size they are, and if they are Pontiac or Olds, like stated in the sales info.

racinrod67 · November 23, 2006, 10:09:54 AM

Quote from: "Arnold"
Quote from: "Arnold"
Quote from: "Arnold"
Quote from: "racinrod67"What did this carb come from and what size is it? Casting # on the fuel bowl is 7009094. Atomizer/nozzle # is 7098. The top of the carb has a vent that is actuated by the linkage. Label on the top reads"GM RP 2 Jet Rochester"

The numbers that are CAST #'s on Rochesters,and their parts are really pretty meaningless. I know of NO cross reference/part relation..NOTHING at all to do with those. Oft. wish I had had some info! There must be something,someone.. somewhere that knows about them? Some authority/expert. These are the casting #'s. They are not part #'s Numbers that are actually cast. Raised numbers. I have gone on wild goose chases for those before.They often get confused with the numbers that are stamped on the actual parts,castings.
PART numbers that are stamped are a whole other story. There should be a number stamped into the float bowl somewhere. Probablly vertically.
As has been mentioned..there should be a metal tag with a number on it. These are often so rusted that the #'s..some of them are really impossible to decipher.It is also very nice..haha..when rebuilders don't use the same tag..or one of their own..or a service package or a reman. unit.
The number you gave us here sounds to me like a casting number.? Rochester casting numbers..especially air horns seem to have casting #'s that length with the 0's and are not of even the newer..02/or 04 series of carbs.I could be wrong..but I can check it out for you..or another # Probablly a circular type # cast somewhere. There IS some sort of a code to break these numbers down to a certain point. But that is it. I don't even know where that info is?

I do have a Rochester line manual(9C)...AND the master carb # cross reference from about 1940-1987..that can take me right from a carb.number to a sheet in the manual listing ALL the parts,#'s,Most of the jet/rod.hanger sizes,pictures,applications,years,models,transmissions,engines,kits,updates associated with that # for most carb.s, vehicles. I can help anyone out with that information! I can also go backwards with it to some degree and come very close to finding what carb #/parts,jets,rods etc, should go..or can be built for a specific model/engine.This is not right here..I will be where that info is in a couple of days if you can wait.

I just did a Google for ya..someone says they are centre tri-power J2,Ponch.. from around 1957/8/9 floatbowl castings #'s.If they are casting #'s then I dunno where we can go with that?
I will take a look in my info either today or tomorrow

I just looked for ya..and there is nothing on that #

Thanks for the info. I took a closer look and found an actual number stamped in the base, which looks to be cast iron, not aluminum like the rest of the carb body. Three of the four carbs have 2023 stamped just above the large threaded vacuum port. The fourth carb has a number stamped in the same location but too dificult to make out. As I mentioned before there is a number 7098 cast into the sprayer visible from inside the airhorn. After I removed the top of the carb, there is another number visible on the sprayer - #53. Probably meaningless, but that I would mention it. I have looked the carb over pretty closely and see no other casting or stamped numbers. Would attaching a photo help?

enjenjo · November 23, 2006, 10:32:47 AM

They are small base Rochester 2Gor 2GC. as long as they are all the same size, they should work fine. The Pontiac/Olds carbs flowed a bit more, but the Chevy carbs will work too.

GPster · November 23, 2006, 11:42:07 AM

Just an idea but they might have been selected as the right combination of carbs for a multi-carb set-up. With the carb base numbers being differant the three could not have distrbutor vacuum ports and the odd number being the one for vacuum advance. But I've been wrong before. GPster

racinrod67 · November 23, 2006, 11:15:10 PM

Quote from: "enjenjo"They are small base Rochester 2Gor 2GC. as long as they are all the same size, they should work fine. The Pontiac/Olds carbs flowed a bit more, but the Chevy carbs will work too.

That is what I was trying to determine. The original manufacturer's sales brochure states that either Olds or Pontiac 2GC carbs could be ordered with the manifold. The 2GC was suppose to be the "ultimate in power" providing 14 square inches of induction. I am not sure how this would equate to a total CFM rating. Are these carbs common enough that rebuild kits are readily available?

racinrod67 · November 23, 2006, 11:17:59 PM

Quote from: "GPster"Just an idea but they might have been selected as the right combination of carbs for a multi-carb set-up. With the carb base numbers being differant the three could not have distrbutor vacuum ports and the odd number being the one for vacuum advance. But I've been wrong before. GPster

These are part of a multi-carb Man-A-Fre set up. I just checked, all four carbs have the same style base with a threaded vacuum port.

enjenjo · November 24, 2006, 02:12:44 PM

you can get kits from the local auto parts store. The were used from 55 until 70 or 71 by most GM cars.

Arnold · November 24, 2006, 03:58:29 PM

Quote from: "racinrod67"
Quote from: "enjenjo"They are small base Rochester 2Gor 2GC. as long as they are all the same size, they should work fine. The Pontiac/Olds carbs flowed a bit more, but the Chevy carbs will work too.

That is what I was trying to determine. The original manufacturer's sales brochure states that either Olds or Pontiac 2GC carbs could be ordered with the manifold. The 2GC was suppose to be the "ultimate in power" providing 14 square inches of induction. I am not sure how this would equate to a total CFM rating. Are these carbs common enough that rebuild kits are readily available?

Be careful in disassembling these. I would give these a good spray..especially the area around the gasket surfaces,linkages,valves etc., with penetrating oil..as well as the screw areas. Then I would loosen the screws a bit..spray some more..maybe try and get them a part a tiny bit..and spray some more.The idea here is to minimize damage..aluminum does rot/corrode. Ideally you want to keep the gaskets intact so you can match them up. I would go..to a carb rebuilder and get them.

racinrod67 · November 26, 2006, 01:16:30 AM

Quote from: "Arnold"
Quote from: "racinrod67"
Quote from: "enjenjo"They are small base Rochester 2Gor 2GC. as long as they are all the same size, they should work fine. The Pontiac/Olds carbs flowed a bit more, but the Chevy carbs will work too.

That is what I was trying to determine. The original manufacturer's sales brochure states that either Olds or Pontiac 2GC carbs could be ordered with the manifold. The 2GC was suppose to be the "ultimate in power" providing 14 square inches of induction. I am not sure how this would equate to a total CFM rating. Are these carbs common enough that rebuild kits are readily available?

Be careful in disassembling these. I would give these a good spray..especially the area around the gasket surfaces,linkages,valves etc., with penetrating oil..as well as the screw areas. Then I would loosen the screws a bit..spray some more..maybe try and get them a part a tiny bit..and spray some more.The idea here is to minimize damage..aluminum does rot/corrode. Ideally you want to keep the gaskets intact so you can match them up. I would go..to a carb rebuilder and get them.

I've already disassembled one to find numbers and check jet size. It came apart pretty easily and was surprisingly very clean inside. absolutely no old gas/varnish buid-up. I guess you get lucky every once in a while! What purpose does the vent provide on the top of the fuel bowl? Looks like the linkage opens it when carb is at idle.