Carter AFB question..

[bherder]

... OK, I'm to lazy to read back through 8,000,000 threads... :D

My buddy 'Tom Thumb' (A nick-name to a neighbor of mine who was in Viet Nam and got 7 fingers blown off ... One finger and two thumbs left) GAVE me a AFB off a 318 today. Throttle shafts still NICE and tight. Hell, it's still got the tag on it.
Question:
How do I find out (From numbers) what this carb was supposed to fit, AND if it'll work (Re-jetting I suppose) on a STOCK 360. I'm assuming I don't need anything over 500 cfm, (This is square-bore) .. It has the thermostatic choke and is mechanical secondaries...

(BTW ... Tom Thumb has a Jet-Black 69' Cuda with a MASSIVLY built 440 ... Runs 9 seconds, and is STREET LEGAL ... I'll get over to his shop one day with camera and take pics.. :D You guys would love it... :D )

[85_d250]

That cuda sound almost orgasmic if I don't say so myself...69 was just about the best year for any cay personally...

[volaredon]

post the numbers;

[Speed Dragon]

^ +1

Here's a list of the jet and rod sizes too, might help you.

http://cars.rasoenterprises.com/Carbs-CarterAFB_Jetting.htm

[bherder]

post the numbers;

4294S
J

It's been literally decades since I've taken one of these apart or messed with them ... So if I need to bump anything up in size, would it be jets and rods?

[bherder]

Well, I've found out this much about it...

Late 60's used on Hipo 273-318... Still trying to find out what CFM it is.

If its somewhere around 5-600 I would imagine the right jets/rods would make it very usable. Especially for a bone stock 360.

[Speed Dragon]

Probably a 600cfm. You can try just changing the rods, if it's not enough or doesn't work right then swap jets. Probably just need a rod swap though, or maybe nothing if it's still set for the Hi-Po engine. I'd say put it on and see how it does first.

[sgillett]

Not to be nit-pickey but if I remember correctly it was a 610 CFM
It looks like it is from a '67 273 with a manual trans.
My $.02

[moe7404]

moe in wichita ks i dont want to sound like iam braging , but i have done LOTS of AFBs. its not likely it came off a 60s 318. chrysler didnt make hi po 318 in the 60s. no mater what a rebuild kit says set the float level at 5/16, dont bother setting the float drop cause the float hits the floor of the float bowel before the tang touches. i dont have room to say all thats needed to say about jetting. just this DO NOT change the jet AND rod at the same time, change just one at a time. they had two styles long rod that goes with a domed cover and a tall jet, second style short rod, flat cover short jet, DONT MIX. each carb has one or the other. DONT take out the jets, if you have to take them out dont force them STOP before you strip them out, then call me i have a trick. if you are going to work on the carb on the engine, the first thing is to get 4 good rages. lay two under the carb one on each side, this keeps parts from falling in the open aera in the head. i will try to look up that number tomarow. ill give you my e-mail so we dont burn up to much of DTs server. and if needed i could talk to you on the phone. moe7404@att.net

[bherder]

OK, well from what you guys say/think it sounds like it's be usable on my rig.
General consensus seems to be it's 600 CFM (+-) .. I found a chart on the net about measuring the throttle plate bore and venturi dia. (How does one measure the venturi dia. with out taking it apart first?) But the combination's they listed for primaries/secondaries throttle plate bore don't match what I have.
Primaries are 1 7/16" - Secondaries are 1 9/16" ...
Going to order a rebuild kit for it. I took the choke pull-off off and it's sitting in some water-based degreaser right now just to get some of the crud off. When I rebuild it, it'll go in the 'good' stuff.

Anyway, I took the rods out (domed covers) but left the jets alone. The rods are # 16-403.
I'm temped to follow Speeds advice and see if it works 'As Is', but I'm guessing, it's going to be too lean. And if anything needs changed, yeah it make sense to only change one thing at a time.

But, like I say, it's been decades since I've messed with one of these, and I'm sure there are those of you who can rebuild one of these in your sleep (moe:D ) ... If I need to change rods or jets, and I don't wanna spend a ton of $$ on parts that may end up on the shelf forever unused, given that it's (we think) a 600-610 CFM carb, on a stock 360 ... What size jets/rods would you recommend as a 'starting point' should I need to change anything?

[sgillett]

I looked up the specs for a '66 383 (same size carb), it has .089 primary jets, .0689 secondaries and 16-404 rods.
I would think that would be a reasonable starting point. Maybe try .087 mains...
Good luck
Scott

[moe7404]

moe in wichita ks i havent got to my storage unit yet to get my carter books. i should get over there tomarow .
1.the last year for the 273 hi po was 1967, 1968 hi po engine was the 340 and used a avs carb. as i said be fore chrysler made no hi po 318 in the 60s, and i think( not sure ) none in the 70s. but i think they did in the 90s
2. if its off a 273 i would sell it and then buy a new e-brok. if its a 273 you should be able to get $400-500.
3. be warned the afbs from e-brok and the compatition carter sieres have rods that have to large of a step from the power to cruse step. if you look at the chrysler rods they used way less differance from the power step to the cruse step, this is what you want.
4. the parts price isnt to bad, you may have to go a real speed shop
5. warning this is a very advanced instrution set

[Speed Dragon]

They made a 318 4bbl in the '80s for cop cars and I think some trucks.

[moe7404]

moe in wichita ks i think 1984 was the last year for the thermoquad, i think 1985 used that quadrajunk from gm. its late stop keeping me up past my bed time LOL us old guys need our beauty sleep LOL

[moe7404]

moe in wichita ks i looked up 4294 carter. it is a 1967 273 manual trans. numbers starting with 42 were used only in 1967. i still havent got to my storage i should get over there tomarow.
if it was my carb i would sell it to someone that needs it, you should get $400-500 for it, and get an e-brok

[moe7404]

moe in wichita ks i finaly got to my storage shed, but i cant find my carter books. but i did find my org 1967 dart, coronet, charger service manual. hears what i found afb 4294s is for a stick shift trans, my guess is a 4 speed,throttle bore primary 1-7/16, secondary 1-9/16. main venturi primary 1-1/16(good for gas mileage), secondary 1-1/4.(my guess for cfm is 550). main jet primary .089 secondary .073. low speed jet #66-.033 (idle jet, dont change). step-up rod (2 stage) standard 16-403, 1 step lean 16-372, 2 steps lean 16-370. float setting 7/32, but i have found that 5/16 works better. idle screws 1-1/2 turns, if you have to set mixture screws more than 1/2 turn from 1-1/2, something is wrong

[moe7404]

moe in wichita ks speed dragon gave a site to help gauge changeing jets and rods. how ever that is a very inccuracte system, and convoluted way. i have a computer program that is not only easer to use but more accuracte. ill have to start a hunt for it, it may take sometime, i have lots of stuff to dig through. pardon my spelling.

[bherder]

Hey there moe, thanks for taking the time to look ... And you too Scott ;)
I'm just kinda leaning towards using what I have right now.. Low budget and all.
If it's a 550-600 CFM, I'm guessing it would work well on my bone-stock 360, with proper jetting/rods...
I'm not a 'carb' guy, although I've rebuilt my share... I've just never tinkered much with them as in 'setting them up' or modding one to fit from one app to another. (Especially engines where there is a 90 ci gap)
What I'm finding interesting is the numbers you have for a 273 ci engine, vs. what Scott has for a 383...
Given that (We're assuming ... uh-oh ;) ) that the CFM rating for the two carbs are the same (Or real close) ....

273 primary jets - .089
383 primary jets - .089
(OK, I can live with that :D )

273 Secondary jets - .073
383 secondary jets - .0689 (Or .069 rounded out)

273 metering rods - 16-403
383 metering rods - 16-404

Everything is sounding real close to each other as is.
OK, so is a 404 rod richer/leaner as compared to a 403 rod? And how much difference between the two will it really make?
And isn't a .0689 jet smaller than a .073 jet? Or am I getting it backwards? I'm wondering how you use a smaller jet on an engine that's over 100 ci inches bigger. Unless the 383 secondary bore/venturi is slightly smaller?

I'm real tempted, as Speed suggested, to just bolt it up and see what happens. But I also think when I order the rebuild kit to also order some 404 rods and a couple of sizes of jets between .069 and .073

[Speed Dragon]

Well, my 383 in the Coronet seems to run about right, maybe a hair rich, on .098 jets all round and 7342 rods (.073 idle step x .042 power step).

[moe7404]

moe in wichita ks i have about 15-20 factory service manuals. when i took up carb specs i find that jetting is more a fuction of venturi size than engine cubic inchs, so i recomend start with the jets and rods that are in it. heres an other trick, if you have extra rods you can take a file and file a flat spot in part of the rod that thats in the jet. however it cant be put back.

[bherder]

Mmmmm ..... I guess I'll rebuild it, bolt it up and see what happens...
Although, logic would tell me that a carb set up for a 273 is going to run too lean on a 360..

If I need to richen it up a bit, what would have more effect..(As in just doing one thing at a time) A change in rods or jets?
Does a 404 rod allow more, or less, fuel than a 403 rod?

[volaredon]

that would depend on how you use the 360; that 67 273 whether you know it or not had more HP than your 360 does (stock vs stock anyway) even if that carb is "only" a 400 CFM (I think it's rated around 500 actually from what I can remember) its bigger than the 2 bbl carbs that came on 360s. and the newer vehicles have gotten jetting has become leaner for emissions; (strangely until you get to EFI where they richened things way up and let catalytic converters clean up the mess; never understood that); a HP 273 in a Dart, vs a 360 in a truck/van, used as a work truck take a different tune; advance, jetting, etc; I think that "273 carb" will be fine on your 360; Ive seen 600s on 440s in heavy 1-tons and motorhomes used with good results. I'd definitely try it; I have a #9511, 500 CFM AFB with elec choke that I'd like to try on my 83 318.

[Speed Dragon]

Mmmmm ..... I guess I'll rebuild it, bolt it up and see what happens...
Although, logic would tell me that a carb set up for a 273 is going to run too lean on a 360..

I ran a BBD 2bbl off a 318 on a cammed 360 once for a while, it would still pull hard to 6200 ;)

[moe7404]

moe in wichita ks guess what, i found my carter books. carter jet and rod chart form 5460c rev dec 1967. shows a 403 rod is .069 x .065 and a 404 rod is .063 x .051. note how much diff there is on the 404 rods power step to the cruse step. my opinion is that a mild engine should not have to much diff. but thats just my .02. each engine is different. but i have ALWAYS found that if you stick close to how chrysler did it, thats a good starting point. iam going to try to get my son to wright a program to do the calculations for you, to cal the diff as a percentage, just plug in the dia. when he gets it done i will be able to distribute it. if you have any more numbers to look up just e-mail me moe7404@att.net i can copy the whole sheet and mail them to you. now that i have read my OLD notes, my saying to do the float level at 5/16 may be wrong. ill have to read a LOT of notes be fore i can say what level to set a afb to, but know i got better running with the level higher that carter says, but dont go to far, if fuel is pouring out the discharge nozzles its way to high

[bherder]

Well, this has been a fun afternoon...

Started taking the carb apart. Of course, EVERY little brass screw holding the throttle plates on the shafts and the choke plate to it's shaft.. the heads of the screws all broke off. So I got to drill/tap them all out, and de-burr everything, so the shafts would pull out.
Normally, I'd of left that stuff alone, but I wanted to inspect the shafts, and make sure the thermo-nuclear parts dip got in there and cleaned everything really good. On first fiddle-farting around they seem like they're still nice and tight though.

OK AFB Gurus .. (Moe ... Jeff .... Whoever else :D )
I took jets out to see what was in there .... And numbers we've been using throughout this thread ain't jivin' with what I got. OK each jet has a number stamped on both sides.

The primaries have the same number on both sides - 489
(Does the '4' designate something and the '89' mean .089?)
The secondaries have a different number on each side - 374 & 420
(What number do I believe? Does the '3' designate something and the '74' mean .074?)

OK... What do I have here? And what does it translate into what we've been going over? Is there a 'Carter to English' dictionary out there? :D
(Maybe I'm wrong, but when I see a 'jet size' listed as (Example) .089, I'm assuming the hole in the jet is 89 thousands? Am I right, or just being Joey?)
Normally, I would assume (There we go again) that what's supposed to be in there would be in there, but this carb is over 40 years old, so who knows who did what to it...

Don ... What you say makes perfect sense. Even a small 4 bbl, (Which will be living on top of an Edelbrock) would be an improvement over the stock 2 bbl, and the AFB was on an engine before all this emission/mpg happy-horse-shit, so it may end up working very well as is.. ;)

BTW, THANK YOU very much for all the help thus far guys... :D

[Speed Dragon]

I never take those butterflies off, it's unnecessary for anything but re-bushing.

[bherder]

I never take those butterflies off, it's unnecessary for anything but re-bushing.

Yeah, well, what's done is done.. ;)
I guess I'm just funny that way when I rebuild something ... I want to take EVERYthing apart and get it clean to the bare bones. Plus it would have bothered me not knowing if the shafts were perfectly straight..

Yeesh! I may be Ed's long-lost twin brother!! :D :D :D

[moe7404]

moe in wichita ks iam sorry , i should have said that the t-plate screws are staked, and you have to file the stake off to get the screws out, and you need to stake them when you put it together. and do NOT use lock-tite on them going back together. about the jets carter didnt always follow there own numbering rules on jets and sometimes even rods. any number starting with 4 should be over .1. my old chart shows 120-159 = .089 why cause 120-389 is .089 but its a tall jet, the 120-159 is a short jet. remember they have tall jets and short jets. a good way to check a carter jet for size is to see what size drill goes through with out forceing it, also NEVER drill a carter jet or a holley jet. back to sizes a 374 is .074 tall jet. right now i cant find a 420. in my factory service manual it shows the secondary jet as .073, but doesnt give a number. on my jet chart it shows a .073 jet as 12-175. see they didnt always falow there own system. i know it cant be a .02 jet cause they dont make any thing smaller than .0492. also jets starting with 4 are used in the competition series carbs, thats aftermarket. a carter to english, thats funny. just e-mail me you snailmail add and ill send copys of the charts iam looking at. moe7404@att.net

[fins2fuselage]

Well, this has been a fun afternoon...

Started taking the carb apart. Of course, EVERY little brass screw holding the throttle plates on the shafts and the choke plate to it's shaft.. the heads of the screws all broke off. So I got to drill/tap them all out, and de-burr everything, so the shafts would pull out.
Normally, I'd of left that stuff alone, but I wanted to inspect the shafts, and make sure the thermo-nuclear parts dip got in there and cleaned everything really good. On first fiddle-farting around they seem like they're still nice and tight though.

OK AFB Gurus .. (Moe ... Jeff .... Whoever else :D )
I took jets out to see what was in there .... And numbers we've been using throughout this thread ain't jivin' with what I got. OK each jet has a number stamped on both sides.

The primaries have the same number on both sides - 489
(Does the '4' designate something and the '89' mean .089?)
The secondaries have a different number on each side - 374 & 420
(What number do I believe? Does the '3' designate something and the '74' mean .074?)

OK... What do I have here? And what does it translate into what we've been going over? Is there a 'Carter to English' dictionary out there? :D
(Maybe I'm wrong, but when I see a 'jet size' listed as (Example) .089, I'm assuming the hole in the jet is 89 thousands? Am I right, or just being Joey?)
Normally, I would assume (There we go again) that what's supposed to be in there would be in there, but this carb is over 40 years old, so who knows who did what to it...

Don ... What you say makes perfect sense. Even a small 4 bbl, (Which will be living on top of an Edelbrock) would be an improvement over the stock 2 bbl, and the AFB was on an engine before all this emission/mpg happy-horse-shit, so it may end up working very well as is.. ;)

BTW, THANK YOU very much for all the help thus far guys... :D

B,

I'm so sorry that I didn't pay attention to this thread earlier . . . before you poohed the scrooch with the throttle plate screws. The way to remove them is to deburr them, either by drilling or filing away the burr which keeps them from falling out of the shaft and into the engine. Upon reassembly with new screws, I use red Loctite -- lots of it. Use only steel fillister slot head screws when you replace 'em -- fillisters are the only design which will fit the recess right, and there is less chance of wringing off a steel screw than a brass one.

And Speed is right: the only reason to take those screws out is for purposes of rebushing and/or bead blasting.

Now, the jets. For a 4294, the book says:

Primary = 120-489, .089"

Secondary = 120-374, .074"

Obviously, these particular jet numbers indicate the size but this is not typical of original equipment Carters. Some AFBs were indeed built with different size jets side-to-side in the secondaries but this is not one of them according to my book, so I believe that you are seeing two 120-374 jets and mistaking the "1" for a "4". Hence, it probably has the right jets. If you can find alternate rods, go ahead and play with them but I would not change the jets.

For the record, I agree with Moe that the 4294 should have been sold to an enthusiast with a '67 Barracuda or Dart GT, and then an Edelbrock performer 600 bought for your application. I don't know if you could have got a small fortune for it, but I'll bet it would have brought $150 - $200 on eBay. It would have been worth your while to then spend the extra bucks for an Eddy.

Jeff

P.S.

After you got the throttle shafts out, did you notice how their bores are relieved (i.e., not bushed) part of the way through? Factory "sabotage" -- they were made to wear out prematurely! We rebush 'em the rest of the way through with thin-wall brass tubing.

J.

[moe7404]

moe in wichita ks you should NOT have used Loctite of any kind, now to taked it apart you will have to put a tourch to them, heat will release Loctite. and dont put the jets very tight just two fingers on the screwdriover, they DO NOT try to come out.

[moe7404]

moe in wichita ks. i use a spot facer mounted on a drill rod, it by the pilot hole. and i go to a bearing supplier and get oil-lite bushings. just be carfull and dont break into the throttle bore, cause then youll have to push the bushing into the bore , and then file the bushing to match the bore. the most important part is getting the right oil-lite bushings. if you get the oil-lite bushings. i got the inch long cause it was the same price as a 1/2 long bushings. but you have to to cut the one inch to 1/2 inch. dont use a lathe, use a hobby razer saw by puting it on the drill rod to hold it

[fins2fuselage]

Moe,

That is what I like about my Loctite: no filing, just a little heat! Since the base is removed from the carb for this operation anyway, there is on fire danger. Of course, either method -- stake or Loctite -- works equally well.

You are exactly right about the hassle involved in contouring bushings to the curvature of the throttle bore -- it is a hassle. I find it is easier in the long run to drill straight through on a 1-bbl. and simply go ahead and contour, but with 2- and 4-bbls. it really is too much hassle. When I do have to contour the bushing, I do it prior to installation so that I don't risk gouging the throttle bore with the file.

I used to use bronze oilite bushings, but the thin-wall brass tubing I now use is so much easier to work with, especially when I go to finish the ends. It requires much less material removal from the throttle body, and it allows me to rebush bases which would otherwise have too little "meat" around the shaft to counterbore for the thicker oilite bushings.

Another advantage is that my brass tubing is available in a wider range of sizes so that I can do odd-sized shaft bores (such as 9/32" I.D.). I get it from Special Shapes, a division of K&S. You can contact them at 1-800-51-SHAPE if you should ever want/need to try the brass tubing.

For the novices out there, I would discourage you from trying this operation at home with any type of bushing material. It has taken guys like Moe and me much practice to perfect our techniques.

Jeff

[bherder]

so I believe that you are seeing two 120-374 jets and mistaking the "1" for a "4". Hence, it probably has the right jets. If you can find alternate rods, go ahead and play with them but I would not change the jets.

You're probably right... even with my gigantic magnifying glass, it was very hard to read the numbers on the jets ... But what you're saying makes sense and clears things up in my head ;)
And I like the idea of only playing with rods as they're very easy to get to..

For the record, I agree with Moe that the 4294 should have been sold to an enthusiast with a '67 Barracuda or Dart GT, and then an Edelbrock performer 600 bought for your application. I don't know if you could have got a small fortune for it, but I'll bet it would have brought $150 - $200 on eBay. It would have been worth your while to then spend the extra bucks for an Eddy.

Well, if I did that, it'd mean it would have sat on a shelf forever.
I refuse to use ebay anymore because:
A - Their firearms policies..
B - That you HAVE to have a Paypal account..

After you got the throttle shafts out, did you notice how their bores are relieved (i.e., not bushed) part of the way through?

Yup... It looked like only about 25% of the shaft (Not counting the middle, where the plates are) made contact with the bore on the base.
But another reason I disassembled all that was the secondaries shaft seemed real stiff in it's movement. Even after linkages and springs were removed. I took some scotchbrite to the shaft and it moves freely now.
BTW, I don't think I'll have it bushed ... both shafts seem like there is still a nice snug fit to them.

[moe7404]

moe in wichita ks jeff: its so cool to talk to someone that realy knows carbs. you are right about doing it different ways. my father-in-law used to say" theres a dozen ways to skin a cat" he was a electronics enginer a Boeing. he didnt buy a color tv till rca made the xl-100. he said thats how a color set should be made, of course that was a long time ago. i was at boeing in wichita for 25 years. to: bherder you are right about the trouble selling on e-bay. is there other sites for selling stuff? i found my old program to calculate the change in jeting, for afbs. it will even calculate it if you change both the jet AND rod. its writen in basic for a commodore 64, now i need to be rewriten for windows (choke) and linux, my favorite. if you know someone that can do that let me know, thanks. be fore warned it takes a lot of debuging.

[bherder]

to: bherder you are right about the trouble selling on e-bay. is there other sites for selling stuff?

Craigslist is pretty popular ... In fact that's where I found the Caravan for my youngest son.. And DT has a 'For Sale' forum...
But I'm looking at it this way ... If it'll work and I put the work into it, dammit, I'm gonna use it :D

i found my old program to calculate the change in jeting, for afbs. it will even calculate it if you change both the jet AND rod. its writen in basic for a commodore 64, now i need to be rewriten for windows (choke) and linux, my favorite.

DAMN!! I KNEW I shouldn't have sold my ol' 64! ;D

if you know someone that can do that let me know, thanks. be fore warned it takes a lot of debuging.

[fins2fuselage]

B,

If your shafts have the least bit of bind in them when you get them re-installed, let me know before you install the right-side levers and I will give you the shop trick for freeing them up.

Moe,

Same here! We all have our talents; apparently, I inherited my carburetor skills from my grand-daddy.

Jeff

[moe7404]

moe in wichita ks i got my carburetor skills from my auto mech teacher he had a realy great way of teaching auto mech. he would tell what a carb did to how fast the car was going. a LONG time ago 1967. my dad thought it was great that i knew what each hole in a carb did. i just thought of somthing, sometimes i would leave out the two middle screws if i knew i was going take it apart soon.

[bherder]

Well, I'm glad that you guys are on this forum! :D

I know my way around carbs, but I'm by no means a guru/expert. Especially on I carb I haven't fiddled with for 30 years.

I guess Jeff, that you'll never have to worry about being unemployed with your skills (Sounds like you got a good backlog going) ;) You know what I find rather amusing is, you'll get some of the younger guys on this site, and others, who say 'I know nothing about carbs'.. I know it's not their fault, just because they're young, but having grown up in the 60/70's this always just sounds really odd to me. I always get that 'quizzical dog look' ;D

Anywho, the carb is mostly apart and on the bench. It's gonna have to wait a few days for some 'deep' cleaning. I've got this water based stuff in my parts tank, but the stuff is kinda whimpy-whampy. (The sticker on it said to ONLY use water based solvent .. I don't know if they're just trying to be 'eco-green' ... Or if anything else will melt the plastic housing of the pump)
But I was looking at my bucket-o'-parts dip (The brutal stuff) and it's getting kinda' thick, so I need some new/clean stuff.

So when I get this all back together, lets say it needs some tweeking. And I'm only playing with rods. It's got 403's right now.
I'm assuming (!!) sizes before/after would be a 402/404? Is that right? OK, lets say I need to richen it up a bit.. Which direction do I go? (I can get rods from NAPA but they have to be ordered..)

[volaredon]

Lemme put it to ya this way; I grew up during the era of some of the WORST carburetors ever made; Mikuni (Minivan 2.6) Furd Variable venturi and about any "feedback" carb ever made; also I started wrenching for a living thru the earliest computer controlled FI systems, and got out of wrenching just as the newest "CAN" systems were coming out; given all that my last 2 vehicle purchases were carbureted 318s!!!!! Given a choice I'd much rather play with a carb and distributor than ANY computerized setup! I pd $3500 for my Snap on MTG 2500 (graphing) about a year before changing to industrial maint; and I'd rather NOT have to dig out that scanner!

[Speed Dragon]

Carbs are cool for their simplicity, but EFI > carbs all day long IMO. It's just a better way of doing the same job.

[AMP762]

I"ll agree FI is great for everyday driving,but I can make a carb do about anything I want.I don't know enough computoress to do that with FI.If my carb. quits out in the boonies I can make it come home,can't do that with FI.

[fins2fuselage]

Well, I'm glad that you guys are on this forum! :D

I know my way around carbs, but I'm by no means a guru/expert. Especially on I carb I haven't fiddled with for 30 years.

I guess Jeff, that you'll never have to worry about being unemployed with your skills (Sounds like you got a good backlog going) ;) You know what I find rather amusing is, you'll get some of the younger guys on this site, and others, who say 'I know nothing about carbs'.. I know it's not their fault, just because they're young, but having grown up in the 60/70's this always just sounds really odd to me. I always get that 'quizzical dog look' ;D

Anywho, the carb is mostly apart and on the bench. It's gonna have to wait a few days for some 'deep' cleaning. I've got this water based stuff in my parts tank, but the stuff is kinda whimpy-whampy. (The sticker on it said to ONLY use water based solvent .. I don't know if they're just trying to be 'eco-green' ... Or if anything else will melt the plastic housing of the pump)
But I was looking at my bucket-o'-parts dip (The brutal stuff) and it's getting kinda' thick, so I need some new/clean stuff.

So when I get this all back together, lets say it needs some tweeking. And I'm only playing with rods. It's got 403's right now.
I'm assuming (!!) sizes before/after would be a 402/404? Is that right? OK, lets say I need to richen it up a bit.. Which direction do I go? (I can get rods from NAPA but they have to be ordered..)

B,

I don't really fool around with too much aftermarket carburetion (mostly OEM), so I don't know exactly what the 402-403-404 designations represent.

Let me do a little research and try to get some answers. This is an Edelbrock, right? You could always call the Edelbrock carb tech line (California). Talk to "Don" there, he is the E-brock guru!

Jeff

[bherder]

Let me do a little research and try to get some answers. This is an Edelbrock, right?

Well, I guess nowdays it is ... ;)
But no, this is an honest-to-God 42 year old Carter AFB....
Moe says there is a difference on the rods between the Eddy's and the old Carters... If you can find out, that'd be great, but don't go through a whole lot of trouble on my account....
I did mic the rods today and the 403 rods (At least mine) are .058" on the tip/skinny end and .067" on the upper/fat end... If that means anything...

[moe7404]

moe in wichita ks i need to warn you about Edelbrock. most of the time they have rods that have to much difference between the power step and the cruse step. just compair chrysler rods to Edelbrock rods.

[fins2fuselage]

Let me do a little research and try to get some answers. This is an Edelbrock, right?

Well, I guess nowdays it is ... ;)
But no, this is an honest-to-God 42 year old Carter AFB....
Moe says there is a difference on the rods between the Eddy's and the old Carters... If you can find out, that'd be great, but don't go through a whole lot of trouble on my account....
I did mic the rods today and the 403 rods (At least mine) are .058" on the tip/skinny end and .067" on the upper/fat end... If that means anything...

B,

Brain fart . . . I knew that!

And Moe is right about the step locations of the E-brock rods -- they probably won't work properly in an AFB. They may actually be physically too long as well, in an AFB as old as yours.

Jeff

[moe7404]

moe in wichita ks my son is rewrighting a program ( one for windows one for linux) to cal % of change. ill put together some charts and the programs, with some instructions. a small fee will be needed to cover ink and postage. but iam not sure when ill get all this together. ill post again when i know more.

[fins2fuselage]

B,

Okay, after a bit of research I would recommend that you use either 16-160 rods (1 size lean for carb # 4298 from a ’67 383) which measure .0645 x .062 x .055;
or 16-171 rods (2 sizes lean, same application) which measure .066 x .064 x .058. The 16-404 standard rods for the #4298 carb are probably a tad too rich at .063 x .060 x .051.

All of this presumes that you can even locate these part numbers and that (if they are used) they are not worn out at the top where they pass through the metering piston, a common problem.

Jeff

[moe7404]

moe in wichita ks my experance has been that .0015 dia change in a mettering rod makes VERY little difference in the amount of fuel. but dont forget like i have said before a jet of .101
from .100 is a bigger change than that of a rod of .060 going to .061. simple matter of serface area.

[Speed Dragon]

Dude, just put it back together and try it. You'll know if it's lean when you get on it a bit. It'll cut back like it's running out of fuel (which essentially it is:) ). If so, then worry about finding rods. I doubt if you'll get snowed in and need the truck at this time of year, even in WA :) and they are easy to swap out with the carb installed on the engine. I believe I did use Eddy rods in the old AFB I had, so worst comes to worst you can use them (assuming it's not the other old style Moe was talking about). My AFB had the same kind of jets in it also. I have no idea what it was off of originally though.

[Speed Dragon]

I"ll agree FI is great for everyday driving,but I can make a carb do about anything I want.I don't know enough computoress to do that with FI.If my carb. quits out in the boonies I can make it come home,can't do that with FI.

I don't see why not. unless the fuel pump dies, or the distributor sensor quits, then EFI will still run. Either of those quit on a carbed vehicle and your stuck also. Some efi systems use a crank sensor also, which can die and leave you stranded. But in reality, it's kinda like the Mopar vs HEI ignition debate. Everybody has heard of all these horror stories about being stranded with them, but how often has it really happened to one person?

I could go on, but I'm gonna stop before I hijack another thread w/ my ranting :D

[bherder]

Dude, just put it back together and try it.

Oh, I am ... It's just if I need to make changes, I want to understand what I'm doing and why I'm doing it and what direction I'm going etc etc.
I know, a funny quirk .. ;)

[moe7404]

moe x2

[bherder]

Well ..... I've just got freekin' carburetors falling out of the sky now. :D

The local 'Crusty O'l Mechanic' gave me a used Edlebrock 1406 he had sitting in the back room for a couple years. Were I going to go and buy one this is the one I would have bought (600 cfm - 'econo' 4bbl for a stock or very mildly built small block) ... So this worked out great. It's got Furd linkage on it, but no prob, I'll use the Mopar linkage off the AFB. And the carb kit I bought for the AFB from NAPA, must be a 'one-size-fits-all' as it came with various different gaskets, which I assume covers the AFB/AVS/Edelbrock carbs.

Has the electric choke on it (:D !) and the shafts seem nice and tight.

Which leads me to this question.. The Secondary shaft seems like it binding a bit. Jeff! Moe! my main men! ... ;) ....You mentioned in a previous post about shafts binding and how to fix it? So, being as you mentioned that specifically, I assume this is not an uncommon thing? The secondaries open with a little help from my thumb on the other hand, but they don't open nice and easy just working the linkage normally.
So anyway, it is dirty and used and has been sitting on a shelf for awhile, which I'm sure doesn't help, but what if an over-nite soaking in carb dip doesn't cure it? What next?

(BTW, I will NOT be taking the throttle shafts/plates apart on this, unless I have to :D )

Thanx a ton again.... ;)

[moe7404]

moe in wichita ks first thing is to clean it. do NOT take out the jets, do NOT take out the shafts, yet. after cleaning look at the screws that hold the blades in, the end opp the screw head should be a little higher than the shaft. if it is then it hasnt had the blades removed and thats good. now look at the bores where the blades close down next to the shaft, if it has heavey scrape marks, that means the shaft is bent, or the blades are not seated in the bore. any time you take the blades out you have to seat the blades to the bores, its not as easy as just throwing them in. you half to check the fit in the bore, the blade must fit so perfict theres NO light coming through, you WILL have to work with it. to take the shaft out you must first file down the stake on the side opp the head, it should be flush with the shaft. then and only then you can take out the screws be VERY slow takeing them out. but first scribe an alinment scribe on each blade to bore, and give each one a number or letter so they can go back in the same bore. now get a stright edge and check shaft strightness, if it needs strightened be carefull, put the blades in if needed to keep the slot in the shaft from colapesing. i have never seen a bent shaft, but it could happen. sorry some of this stuff is not in a good order. on the secondary shaft and primary shaft, on the pass side is some linkage and springs, the pri isnt to bad, but the secondary is lot harder, but there is no secret what you see is what you get, but the spring has lots of force. if you need anything just e-mail me moe7404@att.net

[bherder]

Hey there Moe ... Thank you very much for the reply.

Between the last post and now, I was out in the shop fiddle-farting with it.
I'm sure now that all it need is a good cleaning and rebuild. I cleaned up some of the outside linkages with some carb spray and let a little 3-n-1 oil trickle into the throttle shaft bores. They work smooth as silk now.
I did check the bores as you suggested, and they are spotless, so far as having any kind of scratches on them. I did notice with this one, being as it has the electric choke on it, unless the choke is partially open (Basically anything more than fully closed from what it looks like) it holds up an 'arm' on one side of the carb, that has a tang on it, which won't let the secondaries open anyway.
So once I cleaned a little bit of the crud off, dripped a little oil on things, stuck a hunk of wood dowel in to hold the choke slightly open... Smoooooooth operation. :D

Hell, I'm doing pretty good here. I've got two carbs for free... Rebuild kits for each are $31.00 ... Couple of gallons of fresh carb dip $30.00... I could end up rebuilding both, sell the the AFB, keep the Eddy, and by the time I get new intake manifold gaskets and some coolant ... break even. Not too bad for a free upgrade. (Eddy carb and intake manifold..) ;)

[fins2fuselage]

B,

AS Moe said, disassemble and clean the carb first (but do NOT remove the throttle plates/shafts!). Moe, actually, it is usually the right-side lever set-up on the primary shaft which has the ultra-strong spring. The secondary lever and spring can be removed and re-installed without much drama. At least, this is the case with the old-style AFBs.

Okay: if soaking it and following-up that with some good spray carb cleaner (I use Berryman's B-12 or sometimes CRC Clean-R-Carb) doesn't do it, you may have a bent secondary shaft -- and Moe, I have seen more of those than I can remember! Here is how to straighten the shaft:

With the right-side lever removed from the secondary shaft (retained by truss-head machine screw), use a 1/4" - 5/16" pin punch to smack the shaft squarely, just inside the throttle bore and adjacent to the points where the shaft goes into the casting. Yes, I know it sounds nuts -- but it works! Now, flip the shaft over almost 180 degrees (which you can do with the lever removed) and do it again from the opposite side. Don't strike the screws or plates, only the shaft. Each time you hit it a lick or two, try it and see if it has freed up. When it becomes free, stop smacking it! If this doesn't work, corrosion or dirt is present in the throttle shaft bores and it will have to come out per Moe's description.

Moe mentioned seating the throttle plates in the bores correctly. Here is the easy way to do that:

Install a #10-32 "sacrificial" screw into the right shaft end (where the lever screw would go). Position the throttle plates fully closed, and take that hammer and smack both ends of the shaft alternately until the plates seat in the bores and you can't see any daylight around 'em! You will want to use a flat punch on the left end so as not to damage the throttle lockout tang on that end. If the shaft has been removed, perform this operation while the screws are still about 1/8 turn loose.

Good luck!

Jeff

[moe7404]

moe in wichita ks to:fins2fuselage i tip my hat to you, with out a doubt your a better expert on afbs than i. on the springs i just had a major brain fart. its been 10 years sence iv had one in my hands. the other things you listed are VERY top notch also. there are servel things that happen when you get old but i cant remember what they are.

[charlie1935]

moe in wichita ks to:fins2fuselage i tip my hat to you, with out a doubt your a better expert on afbs than i. on the springs i just had a major brain fart. its been 10 years sence iv had one in my hands. the other things you listed are VERY top notch also. there are servel things that happen when you get old but i cant remember what they are.

Hey Moe, you loose 3 things when you get old.
Your memory and I forgot the others. :D

[Parson4]

My $.02

Boyyyyyy y'all is a bunch of brainy fellers, cause it's ALL GREEK TO ME !!!

Nuff Said from da dummmmmmie down on da ranch :D

[charlie1935]

Hey, Rick! Good to see you on here.
This old man was wondering about you.

[fins2fuselage]

My $.02

Boyyyyyy y'all is a bunch of brainy fellers, cause it's ALL GREEK TO ME !!!

Nuff Said from da dummmmmmie down on da ranch :D

Rick,

Speaking only for myself, I'm certainly not a brainy feller but rather a one-trick horse. I restore antique carbs for a living so I know a few carburetion secrets, but most of the time I can't figure out where I left my own shoes!

Jeff

[moe7404]

moe in wichita ks well i talked to my son, he is wrighting a computer program to calculate how much you have changed jetting when you change a jet and a rod. when you change a jet and rod you cant guess what change you made, this program will cal this for you. he is going to make it so it will run in windows or linux. he said it will run in the web browser of eather o.s. but he may not get it done soon. after he finishes it, ill have to test it to see if it matches the one i did for a commodore computer years ago

[Speed Dragon]

I'm sure you can figure out what percentage difference there is between different sizes w/ some math.

[AMP762]

My $.02

Boyyyyyy y'all is a bunch of brainy fellers, cause it's ALL GREEK TO ME !!!

Nuff Said from da dummmmmmie down on da ranch :D

Parson how ya'll been.I'm a betting you know the good book purty good,same with carbs.you look at it enough you start to understand.

[Parson4]

B,

Okay, after a bit of research I would recommend that you use either 16-160 rods (1 size lean for carb # 4298 from a ’67 383) which measure .0645 x .062 x .055;
or 16-171 rods (2 sizes lean, same application) which measure .066 x .064 x .058. The 16-404 standard rods for the #4298 carb are probably a tad too rich at .063 x .060 x .051.

All of this presumes that you can even locate these part numbers and that (if they are used) they are not worn out at the top where they pass through the metering piston, a common problem.

Jeff

Well Jeff all that there stuff sure sounds awful techie to this pooooooor old dumb steer wrangler, but then on the other hand, all you younguns like Bruce & Speeeeeedy know a whollllllle lot more than us "brain bake" oldies from da desert....... HuH Charlie ??? :D

[Parson4]

Speakin of Charlie, howdy pardner !! Howdy to you to Amp, what y'all been up to since last time I was here?? :huh:

[Speed Dragon]

Lol, well it's like Amp said, after looking at them for 14 years... :) I did a Eddy on a '68 Coronet wagon yesterday.