$21
Vacuum Issue?
Thread Starter
Cruising
Joined: May 2013
Posts: 13
Likes: 0
Vacuum Issue?
So this question has to do with the vacuum.
My 77 fires right up cold. But after running at idle for about 5 minutes or so it starts to bog down and eventually shut off. Sometimes she'll fire up again but mostly i'll end up running down the battery.
I know i have some vacuum pluggs dry rotted and in poor shape that i got to replace, but i am wondering if a poor vacuum system would cause this symptom?
Thanks for your inputs. All are welcome.
My 77 fires right up cold. But after running at idle for about 5 minutes or so it starts to bog down and eventually shut off. Sometimes she'll fire up again but mostly i'll end up running down the battery.
I know i have some vacuum pluggs dry rotted and in poor shape that i got to replace, but i am wondering if a poor vacuum system would cause this symptom?
Thanks for your inputs. All are welcome.
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Check your choke pulloff setting & operation and your choke operation & adjustment. If the pulloff is incorrectly adjusted or ruptured, or if your choke is incorrectly set or inoperable, it will cause the symptom you describe. A restrictive or partially plugged fuel filter will seldom cause an engine to die at idle.
Lars
Lars
Thread Starter
Cruising
Joined: May 2013
Posts: 13
Likes: 0
Check your choke pulloff setting & operation and your choke operation & adjustment. If the pulloff is incorrectly adjusted or ruptured, or if your choke is incorrectly set or inoperable, it will cause the symptom you describe. A restrictive or partially plugged fuel filter will seldom cause an engine to die at idle. Lars
You were correct....the choke system was incorrectly set even on the newly replaced carb.
So i looked deeper and also found a weak/bad EGR valve and an issue with the choke heater tube. So when I removed the choke heater tube (mounted into the intake) i saw that the tubes were cut and pinched. Have you (or anyone out there) have an idea why this would have been done?
So now I am in need of trying to find a complete one to replace it. Does anyone know where ir who might sell these? I have checked with all the local auto parts stores and the major corvette vendors as well. No luck.
I live in northern New Mexico @ about 5500ft elev. so i would like to ensure my choke system is correct.
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Advanced
Joined: Aug 2009
Posts: 65
Likes: 0
From: Rio Rancho NM
Check your choke pulloff setting & operation and your choke operation & adjustment. If the pulloff is incorrectly adjusted or ruptured, or if your choke is incorrectly set or inoperable, it will cause the symptom you describe. A restrictive or partially plugged fuel filter will seldom cause an engine to die at idle.
Lars
Lars
As I previously mentioned, I have a newly replaced Rochester Quadjet Carburetor, new replacements for the EGR valve and choke heater tube assy. Fired her right up at cold and ran for about 10 minutes, shut her down and went to restart but would not fire up. She turned strong but would not start...as though no fuel was getting into the carb.
Did a visual into the jets and i did see fuel spray.
Any thoughts/Ideas???? Anyone?????
Melting Slicks
Joined: Oct 2003
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From: Chapel Hill NC
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Recently my Edlebrock carb would fire up, run a few minutes and then sputter and die. It was a leaking float. Gas would evaporate from the carb while sitting so there was no flooding initially but then as the fuel bowl filled at some point the carb began to flood the engine and cause a stall. Could hear gas sloshing around when shaking the removed float. Replacement solved the problem.
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Lars