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| | | Forums66 Topics128,154 Posts1,057,014 Members48,460 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jan 2014 Posts: 3,690 'Bolter | | 'Bolter Joined: Jan 2014 Posts: 3,690 | Good points, Bill. I’ve never put much effort into figuring out how long it takes for the fuel to evaporate in my carb.
The YF is awesome. Starts up stupid-easy, like first rotation, as long as it has fuel. And I can push in the choke almost right away as long as I pull the throttle cable just a hair. That’s in moderate to hot weather. Winter time takes just a bit longer.
A “next day” start is also instantaneous. Shooting from the hip, I’d guess that a week of sitting equals 5 seconds (more or less) of cranking. I interpret that as a pretty empty bowl. Maybe not totally dry.
Last edited by JW51; 06/03/2024 2:23 PM.
1951 3100
| | | | | Joined: Jan 2022 Posts: 2,485 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,485 | I can push in the choke almost right away as long as I pull the throttle cable just a hair. That’s in moderate to hot weather. Winter time takes just a bit longer. Same with mine. Pull the choke about half way for cold starts and kick it back to about 1/2 inch when rolling out of the garage less than 5 seconds later. Off by the time I exit my (admittedly long at about 500 feet) gravel driveway. I removed the throttle cable on mine and moved the choke cable down to the throttle cable position on the dash to allow more room for my electric wiper motor. I've found that the first half inch of choke cable pull doesn't actually start to close the choke, but it does bring on the idle speed cam enough to kick up engine RPM to 800-850.
Last edited by Bill Hanlon; 06/03/2024 2:40 PM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Oct 2021 Posts: 6,941 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,941 | Check to see how long it takes for the fuel bowl to empty by looking down the throttle and goosing it by hand. Once you stop seeing the accelerator pump squirt, you'll know how long in between starts it takes to drain. Fill up the fuel bowl before that happens to keep the diaphragm submerged in fuel by running your electric fuel pump, or cranking the engine to get the gas up into the bowl.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: Nov 1995 Posts: 5,740 24601 | | 24601 Joined: Nov 1995 Posts: 5,740 | OK, you guys have me gun shy now.... if all these parts and kits are "pricey...." Please define that better.
~ John A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult. 1949 Chevrolet 3804In the Legacy Gallery | In the Gallery Forum1973 IH 1310 Dump1963 Kaiser M38A12001 International/AmTran RE3000 "Skoolie"2014 Ford E-350 4x4 (Quigley) | | | | | Joined: Nov 2002 Posts: 2,767 Carburetion specialist | | Carburetion specialist Joined: Nov 2002 Posts: 2,767 | John - check your messages.
Looks like I used up one more of my chocolate flavored shoes when I replied John might want to go up a couple of thousanths on the main jet without looking at the spec sheet. Carter made a few YF carbs where the main metering jet is pressed into the body assembly and IS NOT GENERALLY THOUGHT TO BE REMOVABLE (Jerry - hush, not everyone can pull a pressed-in jet, make a new one on a jewelers lathe, and press it into place!). The 4371s is one of those.
The carb may still be recalibrated, but recalibration is done by changing metering rods. While somewhat difficult to do the math and calculate the diameters to cut the rod; the rod change DOES effect a better calibration change than just changing jets. Just more tedious, and somewhat more expensive. Before actually changing jets or metering rods on any carburetor, one can APPROXIMATE the effects of the change by adjusting the float to change the fuel level by a 1/16 of an inch, which is approximately one calibration size. One can generally save money by testing.
The kit for that carb contains:
1A-31 Flange gasket 17-78 Pump check needle 20-204 Needle seat gasket 20-237 Filter nut gasket 24-27 Float pin 25-965S Needle and seat assembly (spring loaded, correct orifice) 30-87 Bowl filter 30A-44 Idle mixture screw 61-451 Pump diaphragm spring 63-135 Retainer 63-149 Retainer 121-579 Bowl cover gasket 121-172 Pump lifter link gasket 121-319 Bowl filter gasket 121-598 Body flange gasket 150A-10 Pin spring 172-21 Retainer 172-24 Retainer 203-137 Pump diaphragm (red or black to the customer's taste)
If the jet had been replaceable, it would have also been in the kit.
I don't believe prices have a place in the forum threads, John has been supplied with the pricing. If John disagrees, I have no problem with him posting the prices.
Jon Good carburetion is fuelish hot airThe most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes!The Carburetor Shop | | | | | Joined: Nov 1995 Posts: 5,740 24601 | | 24601 Joined: Nov 1995 Posts: 5,740 |
~ John A kid raised on Hotwheels, Matchbox and Tonka cannot be reasonably expected to own only one vehicle as an adult. 1949 Chevrolet 3804In the Legacy Gallery | In the Gallery Forum1973 IH 1310 Dump1963 Kaiser M38A12001 International/AmTran RE3000 "Skoolie"2014 Ford E-350 4x4 (Quigley) | | |
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