Lady72nRob71

The other day I was checking out my 72's carburetor, trying to figure out why the secondaries will not open. There is no distinct howl when I stomp on it, even with an open air cleaner. Performance is okay, but could be quicker (of course!) My 307 in the 86 gets loud when the secondaries open...

Anyway, during my carb adjustment procedure I had to find my carb model number. According to the manuals, the carb it ~should~ have is # 7042250.

However, my carb has these numbers, where the *'s are small dots. Never mind the _'s, I did that to line up the numbers.
*17054937*
___*2183*

That is all there is. What is this??
From what I researched, this is supposibly a 1974 model carb for a motor with an EGR valve (and may not be calibrated for my 72's 350. (Won't help the 4bbl issue though.))
I got concerned about having a non-original motor, but the VIN on the block matched the body, so i was happy there.

So how can I correctly decipher this carb number? I used several web sites to try to figure it out, but most made no sense, like a 75 Caddy with a manual tranny...
Is there an accurate site out there?
I eventually need to rebuild this carb out of PM, and need to know how to rebuild and adjust it right. Can this be calibrated to work with my non-EGR 350?
Any help will be appreciated!

J-(Chicago)

17054937*
___*2183

170=Rochester

5=1980's carb (are you sure it's a 5?)
If it was a 4 its a 70's carb and if a 3 its a 60's carb

4=1984 carb

The place where you have a 9 typed is usually a 2 or a 5....9 seems weird.

(usually)Carb ID
2 = 49 state Q-jet
5 = California and high altitude Q-jet

The next 3 in your carb number makes it a Cadillac carb.
Oldsmobiles have a 5 there.

The last 7 is also very weird. That's the transmission ID. Even's are automatic, and odds are usually manual trans.
7 is an odd number, but I've never seen manual trans caddys

The 2 letters are a plant ID


2183= Manufactured on the 218th day of 1983

J-(Chicago)

Sounds like you have a computer controlled carb No wonder it isn't working right.
I wonder if there's a computer hidden in the car somewhere and a Cadillac 307 distributor in your motor

BILL DEMMER

17054937*
___*2183

170 Rochester model number prefix. 70 is '65-'75, 170 is '75 and up. this is where it starts to get messed up.
..... 702 is '65-'69
..... 703 is usually a service carb. for the 702-series, with exceptions.
..... 704 is '70-'75 (with exceptions) some service carbs. for prior years.
..... 1705 is '75-'79 (with exceptions) some service carbs. for years prior to '75.
..... 1708 is '80-'89 (no exceptions)

5 1970's carb
...8 is 1980's
...6, 7, or 9 is usually used for service carbs. released after 01/01/1980.

4 1974 model year carb. or service carb. model year.

9 emissions designator digit. special emissions certification/non-vehicle application/service carb.
... 2 = 49 state Q-jet.
... 5 = California and high altitude Q-jet.
... 1 is also found here for '65-'67 applications.
... 8 = usually a marine application.

3 generally denotes a cadillac division application or use on a cadillac engine for an external application. it could also be a service carb. number, as those don't follow the general rules.

7 application specification, it isn't always a transmission identifier.

2183= production date code, manufactured on the 218th day of 1973.

with the above stated as only a vague rule, you have a service carb. for a '71-'72 olds 350-455 f-85 and olds excluding toronado. in other words, a one-size fits almost all, service carb. for '71-'72 olds, excluding toronado, released during the 1974 model year.

just in case you're wondering where my info comes from:




bill

J-(Chicago)

Thanks for the clarification Bill!!!

That one was making me dizzy

J-(Chicago)

Bill's bible there should have all correct needles and hangers listed in it to make yours correct.

The carb you have may have been rebuilt by a bread and butter company for a big parts store chain, and may or may not have the correct internal parts.

Bluevista

Why not just get the right number carb that hasn't been messed with and rebuild that? Who knows what they did to that one rebuilding it. You can sell the old one once you know the rebuilt one works or the carb gremlins will get you for being too sure of yourself every time.

I have parts catalog envy.

Allan

Lady72nRob71

J, you freaked me out big time! The 3 beers before reading did not help either...
Glad Bill unfreaked me, at least a little bit. As a sanity check, I double checked the #s and they were right.
Sounds like this may not be what it should be.
I will soon find out about the disty, as I will put in the electronic conversion kit later on. There is NO computer on board, thank God!

Anyone reckon if a rebuild kit for a 7042250 would work in it? I heard the 170 rods may be different...

Anyone got a rebuildable one?? I would feel better this way. Hit me off list if you do.

Thanks to all for helping to clear this up!!

BILL DEMMER

it's a factory service carb. for your application(and a few others). there's no real reason to replace it-if it's working properly. the kits are the same between the two.
however,
7042250 is set up as follows:
.069" primary jets
50B primary rods
7036019 power piston spring
CG secondary rods

17054937 is set up as follows:
.070" pri. jets
50B pri. rods
7036019 power piston spring
CH sec. rods

the differences are very minor compared to the original carb; 1705937 is slightly richer overall by about 8%. this will probably yield slightly better performance.

there are minor differences in the adjustment specs. too, use the 17054937's adjustment specs.


bill

Lady72nRob71

Thanks for the clarification Bill - having that big Rochester Bible must be nice.
Does it happen to list the 17054937's adjustment specs? Is there someplace else I can find them?

For now i will leave it on there, and hopefully I will figure out why the secondaries do not want to open (no physical obstructions).
I do like the slightly richer part...

When it does needs rebuilding, i will determine its fate then. Maybe I will run across the correct carb in between times so everything will be "right".
Thanks again!

BILL DEMMER

the specs. are included in the kit.

does the choke open fully? when the choke is open fully, does the lockout on the secondary air valves disengage? the lockout is located behind the rear of the air horn choke wall, directly in front of the passenger side secondary air valve. when the choke is open fully, there should be .015"-.020" clearance between the lock out tang and the front edge of the secondary air valve.
i can post specific specs; if need be.






bill

Lady72nRob71

Thanks Bill...
So when I buy a carb kit, do I ask for a kit for a 72 Olds with a 350 as if the carb was 'original'?
If so, then i assume I also need to buy the parts mentioned below that are different.

My carb does not have the lockout lever. The pivot hole is there though. My service manual showed this lever also. The choke does open fully when hot.
I also adjusted the air valve spring tension to 1/2 turn like for the original carb, as posted in the SM; no change...

I've started wondering if my throttle cable is even opening the secondaries; I need to check how far the pedal actually opens it...
There are two sets of crappy carpeting in there that will be replaced next month...

BTW, that carb in the picture would look SOOOOO nice atop my 350!

BILL DEMMER

you can ask for a kit for either number-they're the same kit number.
i'd go with the carb. number you're working on(this is for others working on their own carbs.)

make sure you have full linkage travel(pedal to carb.).
it never ceases to amaze me why people start removing parts they apparently don't understand the function of. <<<not directed at you, rob.

the pictured carb. is correct for a '70 cobra jet-so it wouldn't work so well for you. it was just a pic i heisted for illustration purposes.

can you post any pix of your carb?-it might be helpful


bill

Lady72nRob71

Thanks for the help Bill...
Here are a couple pictures of my nasty looking carb...

In second picture, note the idle screw has no real function either (even when fast idle is off.)
I think it has been pretty well monkied up in the past as you implied...

So are all of these rebuild kits the same quality or is there a preferred brand to look for?
I did not think the parts houses would even sell Jjet kits based on carb number, just year make and model. It has been a LONG time since I rebuild a carb, and never a Qjet...

I had been thinking about sending it to a rebuilder so everything will be refurbished, including replating. However, since it is not original, I may just do it myself and clean it up good and call it done...

BILL DEMMER

rob,

since there are issues with this carb. it might be a better idea to send it out. tackling an already fubar-ed qj, can be quite an undertaking. if you had done a few qj's prior, i would say go for it. but, it takes an experienced qj guy to put one back to the way it should be. also, your qj may very well have worn throttle shaft bushings. after you go through it-it still may not work properly.
just a little advice from someone who has un-fugged many a qj.

if you do tackle it yourself- can give you some help.


bill

pizza442

Sorry to resurrect an old thread but a google search for my carb number pulled this thread up so I, too, have the same carb number as Rob: 17054937. My car is also a 72 Cutlass Sup.(coupe) It is a factory 455 car out of Fremont. I have owned it since '94 with 86k orig miles then. I was just pulling it out of the garage to send to Sparky when I noticed the wacky number. (I had swapped it out a few years back and installed an NOS(?) reman by Delco.) So now i'd need to pop the hood tomorrow and see what number is on that one, too. If the numbers are correct as orig and not another service replacement, I'll send that one to Sparky. Silly carbs..
Oh and the four dig code below (manuf. date?) on mine is 2528 so how does that figure?

waterzap

http://www.carburetion.com/CarbNumber.asp

Just plug in your carb number, comes up with all the specs

61reoldsman

I bought a carb off ebay from Johnson's Speed Shop in Lansing ,was a rebuilt one for a 73
Olds but it was way better than the Chevy Carb I had on there !I installed 70 jets ,44 primary metering rods in pace of the 50's ,it was like night and day the difference it made
I don't have an electric choke on there yet but it'll idle nicely after a couple minutes.Sorry didn't read all the way down

Lady72nRob71

Wow - just saw this! The same wacky number, eh?
Maybe it was a run of replacement carbs that were numbered oddly to reflect that...
Mine is still okay, but the accelerator pump dries out and functions poorly if the car is not driven every 3 weeks or so.