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| | | | Joined: May 2011 Posts: 8 New Guy | | New Guy Joined: May 2011 Posts: 8 | Hey everyone, I have been reading about carbs for a few days now and I need some advice on my float drop. I rebuilt my Rochester BC and adjusted the float to the rebuild spec measurements. When the car runs now it has been leaking out of picture A. After driving about 10 miles it was puking gas out of a hole in picture B. I think that my float drop is too low and letting too much fuel into the carb does this make sense? I’m new to carbs guys but I’ve been reading a lot about them. Picture A http://imageshack.us/photo/my-images/43/img00100201105171902.jpg/Picture B http://imageshack.us/photo/my-images/856/img00102201105171902.jpg/
Last edited by ZMi; 07/09/2011 5:15 PM. Reason: clarity
| | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | hard to tell from small pics, but "A" looks like the butterfly shaft, which can be weepy when worn, and "B" looks like the bowl vent, which might mean the float [or needle] is sticking open
Bill | | | | | Joined: May 2011 Posts: 8 New Guy | | New Guy Joined: May 2011 Posts: 8 | cool, im going to tear it down today and check. Any other spots to check while i have it apart? | | | | | Joined: May 2011 Posts: 8 New Guy | | New Guy Joined: May 2011 Posts: 8 | hard to tell from small pics, but "A" looks like the butterfly shaft, which can be weepy when worn, and "B" looks like the bowl vent, which might mean the float [or needle] is sticking open
Bill Hey I have the carb apart and the needle and float are moving freely. I still think its dropping too low | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | The float drop is not important in this situation. The float level is. With the air horn upside down the top of the float should measure 1 9/32 in. from the gasket. If this is correct you must have a piece of dirt in the needle & seat. Measure the float drop from the gasket to the bottom of the float with the float hanging. All this does is keep the float from resting on the bottom of the bowl & posibly sticking.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | Go take the top off your toilet, and push the flush handle. Watch what the water in the tank does. The "drop" of the tank float doesn't have anything to do with how high the water rises in the tank, does it? Your carburetor float works the same way. The "float level" adjustments controls how high the gasoline rises in the carburetor, just like the toilet tank float shuts the water off when it reaches the top of its travel. You need to lower the "float level" adjustment to its correct position and be sure no dirt or debris is allowed to enter the carburtetor (good inline fuel filter)to be sure the needle valve shuts the incoming gasoline off so it can't flood the engine.
Jerry
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| | | | | Joined: May 2011 Posts: 8 New Guy | | New Guy Joined: May 2011 Posts: 8 | Go take the top off your toilet, and push the flush handle. Watch what the water in the tank does. The "drop" of the tank float doesn't have anything to do with how high the water rises in the tank, does it? Your carburetor float works the same way. The "float level" adjustments controls how high the gasoline rises in the carburetor, just like the toilet tank float shuts the water off when it reaches the top of its travel. You need to lower the "float level" adjustment to its correct position and be sure no dirt or debris is allowed to enter the carburtetor (good inline fuel filter)to be sure the needle valve shuts the incoming gasoline off so it can't flood the engine.
Jerry Ha! i fixed the toilet twice today. The float drop is not important in this situation. The float level is. With the air horn upside down the top of the float should measure 1 9/32 in. from the gasket. If this is correct you must have a piece of dirt in the needle & seat. Measure the float drop from the gasket to the bottom of the float with the float hanging. All this does is keep the float from resting on the bottom of the bowl & posibly sticking. I took the initiative to take off the top first then while that was off I rested it so the floats could hand free, I took off the base off and disconnected the throttle, I replaced the gasket with the plastic one from the rebuild kit with the current gasket and made sure the throttle wasn’t leaking. I did the same thing with the intake to manifold gasket. Then I checked the new accelerator pump which is rubber. I checked the floats by eye and to make them drop less basically because “my” toilet was overflowing. The butterfly leak was still there, after I took it for a run, around 50 mph about 2 miles, let it idle for a few minutes, then drove back. Took it for another 2 mile run up some back roads, and opened the hood, problem solved. I think I’m starting to understand carbs, the car did die eventually, but that’s my problem. Thanks again. | | |
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