Got an old Factory redone carb,,Its a GM 2 bbl,,has one big ( what looks like idle screw ) in the front center and the only #s I can find are 700 on bottom of bowl and 2539 under the base. Is the 2539 the base part # or the carb # ?
It looks like a Rochester 2-jet to me. And I see two idle mixture screws in the 2nd and 3rd pictures. The large single thing you're talking about is probably a plug for a vacuum outlet at the back of the carb.
By the way, the part with the fuel inlet is the front of the carb, and the idle mixture screws are also on the front.
well the 1 big screw is just that and has a spring under it does'nt look like a plug thats what im trying to find out
That big knob thing's a mystery to me. Maybe it's a more modern version of a 2-jet for a smog controlled engine. I've never seen that big knob thing on the various exploded view drawings of the older 2-jets that I've seen. Could be from the '70s or something. If you look in a "Motors" or "Chiltons" book from the '70s or '80s, maybe they'll have an exploded view drawing that shows one like that or maybe a written description of what that thing is for. I kind of doubt that's a center carb for a tri-power because I don't think the carb would fit in the middle position with that big thing hanging out the back. The tri-power carbs sit pretty close together. It's probably for some normal 2bbl single carb setup from some smog controlled engine. Probably some lower powered smallblock GM car, pickup, or van. Also, a lot of the tripower carbs have side-mounted fuel fittings. That one's on the front. But who knows. It's a Rochester "2GC" or a "2-Jet" I'm pretty sure. But who knows what it was meant to fit. I'd guess something from the '70s or '80s. It's worth some dough to somebody. The choke alone is worth something.
that big thing on the back looks like an air bleed. But I cant remeber seeing one a 2 jet before. also it does not have an internal filter which led me to the tri power ***umption. it also apears to be a small base which would put it on a small motor or a tri power. also on engines other than the SBC tri powers are not so crammed together. ever look at the **** hanging off the back of a Pontiac tri power center carb. that ****s gotta be 3" long Buick liked using air bleeds. Im thinking Buick or Olds early 60's Edit: notice fuel inlet on the pontiac
This really had me stumped for a little while, so I went out to the garage to investigate. I rebuild quite a few of these carbs and I never saw one of those screws before. I try and buy these carbs at swap meets if I can get them for the right price. I bought 2 last spring as rebuildable cores. Took them home and threw them on a shelf. I looked at them and sure enough one of them had this adjuster on it, at least the tapped hole was there. The actual adjuster and tension spring were gone. I looked it up on a rebuild manual and they call it a ( by-p*** idle air adjusting screw). There should be a 7 digit number stamped on the body of the carb starting with 70****x, along with a couple of other #'s which would indicate the manufacturing date. If these aren't there, then it had a metal that had the #'s on it. I don't see the tag in your pics so I am ***uming that someone removed it. I'm going to investigate this some more and when I find more info I will get back to you. I hope this helps a little. Chuck
Thank you ,,It is a Reman. carb still has the sticker on front so maybe if it had a tag thats where it got missing
I am entering my official guess #7013060 59' pontiac 389 2bbl.. Not tripower....Best I can tell is is it is exact right down to the air bleed
Well, it's definitely not a later model smog 2GC. I have one from a '71 Monte Carlo, and there's a hole on the rear for such a valve, but the carb overall is very different. One big indicator as to its vintage is the choke. hard to believe it doesn't have a number on the side of the fuel bowl housing like this:
Pretty sure this guy knows: http://www.carburetor.ca/ Manual for '58 Tri-power setup-- cool stuff!!: http://chevy.oldcarmanualproject.com/booklets/5802top00.htm
I believe Zbuickman and Heathen have got it right. From what I have found out, it's pre 68 not off a Chevy. There have been some some references to 59/60 Ponchos.
Carb is for a late fifties,early sixties Pontiac or Olds.The large screw is to raise and lower the idle. It's not a tri power carb, the tag is missing and those are the identifying numbers the rest are just casting #s.
Here is a link that will help decipher Rochester carb numbers. I have found this pretty handy. -Joe http://www.oldengine.org/unfaq/leadfoot/qjet1.htm
The number you need is on a triangle metal tag.... There is no way to positivly identifi a carb by casting numbers alone. in 68' they started stamping the carb # on the fuel bowl. Soo with out the tag you can get close, close enough for a kit. For now im sticking to my guess
I have one of those in my hand, also no number, says '59-'63 H.T. Came from the estate of a Pontiac Guy, I don't know what HT means? Anybody want it? I'm S****pen it so speak quick or forever hold your peace..
You must not have noticed that this is a 4 year old thread. OOPS! But since you posted, I will too. H.T. probably means hydra-matic transmission.
4 years ago or last week, when U get as old as I am it doesn't much mater any more, Drive the same hot rod, interested in the same stuff.
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