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#1
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Carter AFB Question
I've been trying to find the correct rebuild kit for a Carter AFB. My question... Is the new accelerator pump supposed to have some resistance at the bottom of the hole as opposed to falling right in? I've tried 2 different kits and the pumps provided are 11/32, I measure the old pump at 3/4 or possibly the less popular 23/32. The carb is a 4242s. Any help would be appreciated.......
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#2
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Call Daytona Parts in New Smryna Beach Florida and they can build a kit with the correct pump and other parts for a 4242 kit. There is a spring that goes into the pump well before the pump.
http://daytonaparts.com/ |
#3
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What material is the pump seal, leather or flouroelostamer?.......
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#4
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I see where your going with that question Cliff!
If it's leather then it's dry from not being in fuel and unswelled so no resistance will be felt during its travel.
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
#5
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Not sure if you purchased a kit from us or not, but no matter.
Carter used pump number 64-328s in the 4242s carburetor. This pump is the same diameter of pumps used in earlier AFB carbs. This pump differs from earlier Pontiac pumps in that it does not have the internal check valve used in some of the earlier pumps, but still the same diameter. One of the "tricks" employed by carburetor tuners on both Rochester and Carter carburetors is to simply bore the pump cylinder out to accomodate a larger pump. The larger cylinder thus has a larger volume which will deliver a larger volume of fuel by the accelerator pump. So, it may possibly be that you have a carburetor that has previously been modified, in which case the pump in any kit listed for a 4242s will be too small. If the pumps you are getting in the kits are physically smaller than the one removed, this is probably the case. However, if the pumps have a leather cup: the manufacturers of accelerator pumps place a cardboard cylinder tightly around the leather to protect the leather. Leather cup washers SHOULD be SLIGHTLY expanded before installation by running a blunt instrument between the leather and the thimble to GENTLY expand the leather. Once expanded, the garter spring will keep it expanded. Jon.
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"Good carburetion is fuelish hot air". "The most expensive carburetor is the wrong one given to you by your neighbor". If you truly believe that "one size fits all" try walking a mile in your spouse's shoes! Owner of The Carburetor Shop, LLC (of Missouri). Current caretaker of the remains of Stromberg Caburetor, and custodian of the existing Carter and Kingston carburetor drawings. |
The Following User Says Thank You to carbking For This Useful Post: | ||
#6
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Further:
Carter used the 3/4 inch pump in their "Competition Series" (read street racing or actual racing) AFB's. Part numbers for the Comp Series carbs: 4758s - 500 CFM 4759s - 625 CFM 4760s - 750 CFM 4761s - 500 CFM (chokeless) 4762s - 750 CFM (chokeless) All of these carbs used the largest pump ( Carter 64-418s). If you find an American manufacturer of this pump, please let me know. I get tired of fabricating them by hand! They have been obsolete for decades! Jon
__________________
"Good carburetion is fuelish hot air". "The most expensive carburetor is the wrong one given to you by your neighbor". If you truly believe that "one size fits all" try walking a mile in your spouse's shoes! Owner of The Carburetor Shop, LLC (of Missouri). Current caretaker of the remains of Stromberg Caburetor, and custodian of the existing Carter and Kingston carburetor drawings. |
The Following User Says Thank You to carbking For This Useful Post: | ||
#7
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Jon, are the 4xxx series pumps different than the 9xxx series? like the 9755 Carbs? I thought all the Carter Comp series were the same.
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66 GTO Nostalgia Super Stock/Street Legal Car 421 CID, stock block, Wenzler Intake, 2- Carter 750 AFB's, 3.90 Gears, Full Factory Interior, Full Exhaust, Stock Suspension 3750LBS 9.77@136.99 Multiple NSCA/NMCA World Champion 66 GTO 389 3x2, 4 speed, 4.33 gear, Montero Red 33K original Miles 67 GTO 2dr Post, 428, Tri Power, 3.55 Gears 80 Trans Am Black SE Y84 W72 WS6 |
#8
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Mike - Carter only made one group of Competition Series carbs:
The 5 numbers listed above on AFB's. Plus TQ 4846s (850 CFM) and 4847s (1000 CFM) The original 9000 series was the high performance street series. After F/M bought Carter, F/M labeled some of the "clones" as Comp Series, but they were not the same. After our first shipment from F/M of the clones, we have had nothing more to do with them, nor will we ever. Jon.
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"Good carburetion is fuelish hot air". "The most expensive carburetor is the wrong one given to you by your neighbor". If you truly believe that "one size fits all" try walking a mile in your spouse's shoes! Owner of The Carburetor Shop, LLC (of Missouri). Current caretaker of the remains of Stromberg Caburetor, and custodian of the existing Carter and Kingston carburetor drawings. |
The Following User Says Thank You to carbking For This Useful Post: | ||
#9
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The 4242S uses a 11/16" diameter and 2.290" long pump, same as all 1966-67 Pontiac AFB´s except 1966 326 engines.
Doesn´t hurt to put a couple of engine oil drops on the leather shirt at install and expand shirt some as Jon said.. |
#10
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Quote:
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Jeff |
#11
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Thanks for all your responses.. The pump material is leather and as far as I know there have not been any mods done to the pump well. I will try to expand the leather and put a couple drops of oil on it. The kits I have are Walker part# 15299B and 15328B which I got locally.
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#12
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Here is a pic of the pumps, though it may be hard to tell the size difference.
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#13
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Quote:
Much different pump. There are about 10 or so different diameter accelerator pump cup leathers. Several of these I either have to mold myself, or if there is significant demand, there is an American company that will mold a minimum of 2500 of one diameter. They range in size from about 5/16 inch to one used by Cadillac on their V-16 that was 1 1/2 inches. Jon.
__________________
"Good carburetion is fuelish hot air". "The most expensive carburetor is the wrong one given to you by your neighbor". If you truly believe that "one size fits all" try walking a mile in your spouse's shoes! Owner of The Carburetor Shop, LLC (of Missouri). Current caretaker of the remains of Stromberg Caburetor, and custodian of the existing Carter and Kingston carburetor drawings. Last edited by carbking; 01-16-2020 at 06:57 PM. |
The Following User Says Thank You to carbking For This Useful Post: | ||
#14
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Quote:
Also looks like the old pump should work fine, if you wanted to save the new pump for an emergency. Put a few drops of light machine oil on the leather to soften it. Jon.
__________________
"Good carburetion is fuelish hot air". "The most expensive carburetor is the wrong one given to you by your neighbor". If you truly believe that "one size fits all" try walking a mile in your spouse's shoes! Owner of The Carburetor Shop, LLC (of Missouri). Current caretaker of the remains of Stromberg Caburetor, and custodian of the existing Carter and Kingston carburetor drawings. |
The Following User Says Thank You to carbking For This Useful Post: | ||
#15
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I get a few AFB's sent here from folks thinking they are Quadrajets. Not soliciting for any of that work, don't want it or any Tri-Power work either.
If/when this happens I use one of the pumps shown below, the larger is the 3/4" version, the smaller is the more common size typically found in AFB's used on Pontiac engines in the mid to late 1960's. I purchased some in both sizes over 10 years ago and not even sure where they came from, but they have been 100 percent successful in this new fuel. Not trying to start a debate over pump cup preferences or anything of the sort, but I sought out these pumps after having a leather pump from a NAPA kit fail in less than 30 minutes! It was exactly like the one in the pic above with the reddish/purple leather material. At a minimum with any carb I do here they are filled with fuel from an electric pump, and I work the accl to insure pump shot. The one that failed worked fine as soon as it swelled up a bit, good to go....WRONG. Went to lunch, came back, moved the throttle arm a few more times before dumping the gas out to dry it up for shipping...NOTHING. Not even a hint of pump shot. I removed the top and the seal was all buggered up prompting me to go in another direction........Cliff
__________________
If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
#16
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I've never had leather fail in 30 minutes but the ethanol laced gas will ruin them if you do not drive the vehicle very often. The gas evaporates and the leather gets hard. You fill the float bowls and the leather softens up and the pump works. Then the gas evaporates and it gets hard again. Then soft again. ta da ta da. Very many cycles of this and the leather will not soften up anymore. IMHO the new ethanol friendly plastic pumps are the better way to go.
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#17
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Great Info Jon!
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Carburetor building & modification services Servicing the Pontiac community over 25 years |
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