jimtash Posted August 29, 2008 Share Posted August 29, 2008 Can someone explain to me why gas is still coming out of the accelerator pump jets after the engine is shut off? Rod is inserted in top hole of bracket.Nothing modified on carb except float level to stock and new needles and seats.Either the gas mileage is horrible or the fuel gauge sending unit in the tank is bad. I can have a 1/4 tank and drive less then 20 miles and it's on empty. I know this can't be right.Thanks. Link to comment Share on other sites More sharing options...
Jim Cannon Posted August 29, 2008 Share Posted August 29, 2008 <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jimtash</div><div class="ubbcode-body">Can someone explain to me why gas is still coming out of the accelerator pump jets after the engine is shut off? Rod is inserted in top hole of bracket.Nothing modified on carb except float level to stock and new needles and seats.Either the gas mileage is horrible or the fuel gauge sending unit in the tank is bad. I can have a 1/4 tank and drive less then 20 miles and it's on empty. I know this can't be right.Thanks. </div></div>From the symptoms you describe, I would say that the carb was put back together wrong. Part(s) missing, probably. The shop manual is not great about some of the details to the carbs. You might also have intended to set float level at factory spec and accidentally got it wrong.It is hard but not impossible for fuel to be sucked down at the rate you describe, particularly if choke is not opening fully. You can't trust gauge, though. Fill tank, drive a good distance (50 miles), then fill tank up again. Link to comment Share on other sites More sharing options...
RivNut Posted August 29, 2008 Share Posted August 29, 2008 You could also have a ground problem on your sending unit. Did you replace the sending unit lately? You don't say whether this is a 63/64 or a 65. There are two different sending units; if you put the wrong one in your tank, you'll not get a true reading. Different ohms for the 63/64 than the 65.Ed Link to comment Share on other sites More sharing options...
tim63riv Posted August 30, 2008 Share Posted August 30, 2008 Jim,I would suspect a misbuild on your AFB. There is supposed to be a check ball and a small brass weight in the carb, directly under the accelerator pump squirters. If that is missing, fuel can and will be pushed or drawn out the squirter nozzles when the car is shut off and RUNNING as well, which could account for the poor fuel economy.45 year old gas gauges are notoriously inaccurate, do like Jim Cannon said and fill the tank and drive 50 miles or so and refill the tank. I trust my trip odometer more than I would ever trust my gas gauge!Good Luck,Tim Link to comment Share on other sites More sharing options...
jimtash Posted August 30, 2008 Author Share Posted August 30, 2008 <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tim63riv</div><div class="ubbcode-body">Jim,I would suspect a misbuild on your AFB. There is supposed to be a check ball and a small brass weight in the carb, directly under the accelerator pump squirters. If that is missing, fuel can and will be pushed or drawn out the squirter nozzles when the car is shut off and RUNNING as well, which could account for the poor fuel economy.Good Luck,Tim </div></div>Ok I took it apart today and there was NO check ball there. Only the needle. The carb kit that I have has the ball in it but I didn't install it because I didn't know where it went. Now that I do, I'll put it in tomorrow. I think that should solve my problem. Thankyou Tim and thanks Jim and Rivnut for your help. I'll definitely let you know how it goes. Link to comment Share on other sites More sharing options...
carbking Posted August 30, 2008 Share Posted August 30, 2008 Carter used a variety of different needles OR balls (NEVER BOTH) as pump check discharge valves on the various AFB carburetors.IT IS IMPORTANT TO USE THE PROPER ONE FOR YOUR CARBURETOR BY CARBURETOR IDENTIFICATION NUMBER!As many kits "almost" fit many more than one carburetor, often both a needle and a ball will be included in the kit. It is the responsibility of the rebuilder to determine which one should be used.Jon. Link to comment Share on other sites More sharing options...
jimtash Posted August 31, 2008 Author Share Posted August 31, 2008 Carbking, Id number is 35035A. Can you tell me if it uses the needle or the check ball? Right now I have just the needle installed.I took it apart, cleaned it out and re-assembled it. For the most part, the leaking has stopped except for a little gas that still comes out of the pump jets. Odd thing is it either comes out of one side or the other but never both and it eventually stops. Is this due more to atmospheric pressure or fuel pressure and the gas is just naturally coming out til that pressure is relieved? Link to comment Share on other sites More sharing options...
carbking Posted September 1, 2008 Share Posted September 1, 2008 <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jimtash</div><div class="ubbcode-body">Carbking, Id number is 35035A. Can you tell me if it uses the needle or the check ball? Right now I have just the needle installed. </div></div>The 3503sa used a square pointed rod, with the point down, as the pump discharge check valve.The fuel coming out of the jet after shutdown is very likely due to the volatility of modern fuel, and the heat of the engine.Jon. Link to comment Share on other sites More sharing options...
jimtash Posted September 1, 2008 Author Share Posted September 1, 2008 Thanks Jon. I appreciate the help very much. Link to comment Share on other sites More sharing options...
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