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Hey all, I have a question. For those that are old school with carburetors, how many pumps of the pedal does it take for your engine to start? For me, with my 72 Supreme (455 with a 670 Street Avenger) it usually takes 3 pumps. My concern is that after I drive it for a while and shut it down for more than say, 5 minutes, when I hit the key, it won't fire back up. I have to pump the gas again. Once running, no issues whatsoever. This has only started recently. I always run the same gas (93 Mobil) and I always go to the same gas station.
The only change is I installed a Thompson Power Blast plate to give me better fuel atomization, so I don't think that's the problem. Do I need to run some fuel system cleaner, and if so, what kind?
Need some additional info. What distributor are you running? What dwell (if applicable) and timing settings are you using? How did you set the carb idle/air screws and how much vacuum does the engine produce? What are the spark plugs gapped at?
Need some additional info. What distributor are you running? What dwell (if applicable) and timing settings are you using? How did you set the carb idle/air screws and how much vacuum does the engine produce? What are the spark plugs gapped at?
HEI ignition, and vacuum and plugs are good...didn't mess with the carb adjustment. As I said, this is all recent. All was good when I bought the car in June.
The only change is I installed a Thompson Power Blast plate to give me better fuel atomization, so I don't think that's the problem.
The first rule of troubleshooting is to review the last change made before an issue occurred.
How can you conclude that installing that device did not affect your previously well running carburetor? I'm not saying the device itself is the issue, but you tinkered with the carburetor and now your carburetor acts differently than it has in the past. Coincidence?
The first rule of troubleshooting is to review the last change made before an issue occurred.
How can you conclude that installing that device did not affect your previously well running carburetor? I'm not saying the device itself is the issue, but you tinkered with the carburetor and now your carburetor acts differently than it has in the past. Coincidence?
I get ya, and that was where my thought process was, but does what I described sound like a carb issue?
My concern is that after I drive it for a while and shut it down for more than say, 5 minutes, when I hit the key, it won't fire back up. I have to pump the gas again.
Exactly what do you do when starting a warm engine? The rule of thumb back in those days, and it says this in the '72 Cutlass owner's manual as well, is that, when starting a warm engine, you press the accelerator pedal about half way and hold it there while cranking. Are you doing this, or are you trying to start the engine without depressing the pedal at all, like you do with a modern car?
Three pumps of the pedal on a cold engine is ok, according to the manual, if the car has been sitting a few days.
Exactly what do you do when starting a warm engine? The rule of thumb back in those days, and it says this in the '72 Cutlass owner's manual as well, is that, when starting a warm engine, you press the accelerator pedal about half way and hold it there while cranking. Are you doing this, or are you trying to start the engine without depressing the pedal at all, like you do with a modern car?
Three pumps of the pedal on a cold engine is ok, according to the manual, if the car has been sitting a few days.
DUH!! Guilty as charged! I will try this and thanks!
November 2nd, 2018, 05:47 AM
