carb flooding
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carb flooding
Hi all,
I have a 77 with a stock 300. It runs very well but when I stop somewhere after it has warmed up, it has problems starting. You have to keep the pedal to the floor while cranking and when it does start it sputters and spews black smoke everywhere. After it cleans itself out it runs great again. Any ideas?
I have a 77 with a stock 300. It runs very well but when I stop somewhere after it has warmed up, it has problems starting. You have to keep the pedal to the floor while cranking and when it does start it sputters and spews black smoke everywhere. After it cleans itself out it runs great again. Any ideas?
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Joined: Jan 2001
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From: S. Mississippi
carb flooding
It sounds like you've got a flooding problem. Or either your bowl is draining over night while the truck sits.
Timing could be suspect, but it sounds more carb related. Is it leaking or anything at the carb? I just had my 1bbl replaced because it was leaking around the top and the float would never stay adjusted, accel pump was shot yadda yadda.
Mine didn't have the bowl emptying when it sat over night, but it did have all the symptoms you are describing besides that.
The choke wasn't working on mine, and it caused it to be a PITA to crank. It was either always closed causing a flooding condition or open, making it worse to crank on cold days.
Check and make sure your choke is operating, look to see if you got any leaks around the carb.
Hope this Helps Ya!
On edit i thought about it, it could be your fuel boiling in the carb from excessive heat... thats something else to think about.
Timing could be suspect, but it sounds more carb related. Is it leaking or anything at the carb? I just had my 1bbl replaced because it was leaking around the top and the float would never stay adjusted, accel pump was shot yadda yadda.
Mine didn't have the bowl emptying when it sat over night, but it did have all the symptoms you are describing besides that.
The choke wasn't working on mine, and it caused it to be a PITA to crank. It was either always closed causing a flooding condition or open, making it worse to crank on cold days.
Check and make sure your choke is operating, look to see if you got any leaks around the carb.
Hope this Helps Ya!
On edit i thought about it, it could be your fuel boiling in the carb from excessive heat... thats something else to think about.
Last edited by desperado_18_2000; Mar 18, 2003 at 07:04 PM.
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carb flooding
Do you have a carb spacer installed?..or the egr spacer? You have the thick gasket between carb and the spacer right? Your symptom sounds like you have a boil over problem - usually happens when the fuel in the carb's bowl gets too hot...because the intakes conducts too much heat to the carb. A nonvented carb will compound the problem. This mimicks a flooded state.
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carb flooding
First thanks... Second I have no idea what a vented or non-vented carb looks like. Third, I do not have an EGR valve, but my carb does set high so maybe there is a spacer? Would a thick gasget help with the heat? Can the float be adjusted to minimize the problem?
thanks
thanks
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carb flooding
A carb bowl vent is hard to miss, it has a large diameter hose running from the front side of the carb opposite the fuel inlet and it runs down to the vapor canister. I'm suprised a boil over problem would happen this time of year - usually a hot summer problem. Feel the base of your carb first before replacing the gasket, I'm starting to think it may be the little shut off valve the the bowl hinges to - it may be sticking open, allowing residual pressure to ovefill the bowl once the engine is off. Carb rebuild kits have new ones that you can use to replace it with, but you've got to open up the carb - might as well rebuild it if you feel confident enough to do it. The nonfeed back carbs, like yours, are not that difficult to rebuild.
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tomias
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
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