Cold start question
Melting Slicks
Joined: Aug 2016
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From: MOUNTAIN HOME Arkansas
Safety Car
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The best thing you can do is to make sure the choke is adjusted properly and closes completely with the first tap of the accelerator pedal.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Your carb has evaporated dry.
Spin the engine over about 10-12 times on the starter, pump the gas a couple times and crank again with your foot off the gas. If it doesn't start, crank a few more revolutions, pump the gas a couple of times and it should start.
50 years ago, this wasn't a problem with and AFB. Today, with today's gasoline seems to be normal.
I've never had a problem starting an engine without a working choke but they come in handy to keep a cold engine running.
Last edited by MikeM; Nov 5, 2017 at 04:56 AM.
Le Mans Master
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Your carb has evaporated dry.
Spin the engine over about 10-12 times on the starter, pump the gas a couple times and crank again with your foot off the gas. If it doesn't start, crank a few more revolutions, pump the gas a couple of times and it should start.
50 years ago, this wasn't a problem with and AFB. Today, with today's gasoline seems to be normal.
I've never had a problem starting an engine without a working choke but they come in handy to keep a cold engine running.
Spin the engine over about 10-12 times on the starter, pump the gas a couple times and crank again with your foot off the gas. If it doesn't start, crank a few more revolutions, pump the gas a couple of times and it should start.
50 years ago, this wasn't a problem with and AFB. Today, with today's gasoline seems to be normal.
I've never had a problem starting an engine without a working choke but they come in handy to keep a cold engine running.
I have an electric choke and use non-ethanol fuel.
Steve
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Army
I've never had the problem even with ethanol gas and different cars/carbs....
Even when I put rebuilt carbs BONE dry on a car, the car starts in 3-5 seconds....
I don't get it when people report this, my feeling is it has to be something exogenous to the carb - fuel pump, venting perhaps ?? I simply don't know.
Even when I put rebuilt carbs BONE dry on a car, the car starts in 3-5 seconds....
I don't get it when people report this, my feeling is it has to be something exogenous to the carb - fuel pump, venting perhaps ?? I simply don't know.
Last edited by Frankie the Fink; Nov 5, 2017 at 07:01 AM.
Race Director
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From: Central Arkansas
Or if you don't want to spin a cold motor for 5 - 10 seconds before pumping and firing - you can get a plastic condiments bottle with a tip, fill it part way with gas, remove the air cleaner and squirt a bit down the primary carb throats and some down the primary bowl vent near the driver side metering rods, replace the air cleaner, pump the throttle 2-3 times and turn the key. It will fire instantly. Kind of your choice which procedure to use.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Review posts #3,4, and 7 for the reason for what you don't know.
Last edited by MikeM; Nov 5, 2017 at 07:43 AM.
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Or if you don't want to spin a cold motor for 5 - 10 seconds before pumping and firing - you can get a plastic condiments bottle with a tip, fill it part way with gas, remove the air cleaner and squirt a bit down the primary carb throats and some down the primary bowl vent near the driver side metering rods, replace the air cleaner, pump the throttle 2-3 times and turn the key. It will fire instantly. Kind of your choice which procedure to use.
Safety Car
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From: Olive branch Ms
Before you attempt to start it one day remove the air filter and work the accelerator linkage. As you do look down in the carb and see if it is skirting fuel from the accelerator pump. I can't believe all of the gas evaporates in a few days. I could believe that the choke might need adjustment.
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Welcome to the forum. With engine cold, remove the air cleaner and see if the butterfly closes when you trip the accelerator rod on the carb. The choke mechanism should close it with about an 1/8 gap or so. The choke tube only draws heated air when it’s running to speed up the choke spring to open the butterfly. There’s a small passage way in the carb and choke housing that can be clogged up with carbon that would slow down the choke opening after its running. How long have you had the car?
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Before you attempt to start it one day remove the air filter and work the accelerator linkage. As you do look down in the carb and see if it is skirting fuel from the accelerator pump. I can't believe all of the gas evaporates in a few days. I could believe that the choke might need adjustment.
Melting Slicks
Joined: Jan 2007
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From: Pasco Florida
Your carb has evaporated dry.
Spin the engine over about 10-12 times on the starter, pump the gas a couple times and crank again with your foot off the gas. If it doesn't start, crank a few more revolutions, pump the gas a couple of times and it should start.
50 years ago, this wasn't a problem with and AFB. Today, with today's gasoline seems to be normal.
I've never had a problem starting an engine without a working choke but they come in handy to keep a cold engine running.
Spin the engine over about 10-12 times on the starter, pump the gas a couple times and crank again with your foot off the gas. If it doesn't start, crank a few more revolutions, pump the gas a couple of times and it should start.
50 years ago, this wasn't a problem with and AFB. Today, with today's gasoline seems to be normal.
I've never had a problem starting an engine without a working choke but they come in handy to keep a cold engine running.
My extensive testing proved it does though.
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
It even dries up in my FI '63 if I let it sit for a couple of weeks.
I don't understand why people keep talking about the choke here? Choke operation has nothing to do with a dry carburetor bowl. Same thing with pumping the gas pedal with a dry bowl.
I drove many years and winters with no choke operation at all on my vehicle(s), even one winter when it got down to -30*F (1963) and I never missed a day of driving. Keeping the engine running that cold day after the Chokeless start was a little rough that day but it continued to run okay after a few seconds.
For those that are interested, pour a little gasoline in a saucer and set it in the sun on a warm day and watch how fast it dries up. Then think about that hot engine that is doing the same thing in the carburetor to the gasoline.
PS. WCFB's don't seem as prone to this condition as the AFB's in my experience.
Put some airplane gas in it if it's a huge burden.
Last edited by MikeM; Nov 5, 2017 at 01:41 PM.
Melting Slicks
Joined: Jan 2007
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From: Pasco Florida
It dries up in my garden tractor fleet after a few days. Lot's of cranking to get started.
It even dries up in my FI '63 if I let it sit for a couple of weeks.
I don't understand why people keep talking about the choke here? Choke operation has nothing to do with a dry carburetor bowl. Same thing with pumping the gas pedal with a dry bowl.
I drove many years and winters with no choke operation at all on my vehicle(s), even one winter when it got down to -30*F (1963) and I never missed a day of driving. Keeping the engine running that cold day after the Chokeless start was a little rough that day but it continued to run okay after a few seconds.
It even dries up in my FI '63 if I let it sit for a couple of weeks.
I don't understand why people keep talking about the choke here? Choke operation has nothing to do with a dry carburetor bowl. Same thing with pumping the gas pedal with a dry bowl.
I drove many years and winters with no choke operation at all on my vehicle(s), even one winter when it got down to -30*F (1963) and I never missed a day of driving. Keeping the engine running that cold day after the Chokeless start was a little rough that day but it continued to run okay after a few seconds.
If I go on a cruise with my 66 with a 425 HP 427 on a 90° day, using E10, the carburetor bowels will be near empty within a several hours after I return home. A hot engine, especially a fat block at 210°, makes fuel in the carburetor evap a lot faster. Just another reason why I don't use that crap! Not even in my lawn mower.
Last edited by Critter1; Nov 5, 2017 at 02:03 PM.
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From: Fresno California
Out where I am, in the land of arid climate and ethanol-laced fuel, the carbs in all my old vehicles are dry after a week or so. No issue, really. And the added advantage of the car being cranked without immediate fire-up is that oil pressure has built up, so when it does light off, it has protection to the bearings due to the oil being where it needs to be already.
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From: Central Arkansas
I've experimented with cranking the motor over for awhile to fill the carb bowl - and using starter fluid - and flipping on my electric pump back by the tank and running it for awhile - and I've not personally had good results with any of them. Usually, I get tired of spinning the cold engine, pump the throttle a couple of times and if the motor will fire, it does so as if it's got half enough fuel - or too much fuel. Half the time it sputters to a stop, sometimes it coughs and coughs and I've even had a backfire or two. If one of these works for you - more power to you.
It's a bit more work but I've found filling the bowl with a squirt bottle and then starting the motor the way it was designed to start works for me - no stalling, no flooding, coughing and sputtering, and no running the starter for long periods of time (anyone who likes to listen to GTX's Chrysler reduction gear starter crank for 10 - 15 seconds is crazy).
And yes, both my Plymouth and Corvette carbs are too dry to fire quickly after a couple of days sitting - particularly in the summer months.
It's a bit more work but I've found filling the bowl with a squirt bottle and then starting the motor the way it was designed to start works for me - no stalling, no flooding, coughing and sputtering, and no running the starter for long periods of time (anyone who likes to listen to GTX's Chrysler reduction gear starter crank for 10 - 15 seconds is crazy).
And yes, both my Plymouth and Corvette carbs are too dry to fire quickly after a couple of days sitting - particularly in the summer months.
Safety Car
Joined: May 2014
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I've experimented with cranking the motor over for awhile to fill the carb bowl - and using starter fluid - and flipping on my electric pump back by the tank and running it for awhile - and I've not personally had good results with any of them. Usually, I get tired of spinning the cold engine, pump the throttle a couple of times and if the motor will fire, it does so as if it's got half enough fuel - or too much fuel. Half the time it sputters to a stop, sometimes it coughs and coughs and I've even had a backfire or two. If one of these works for you - more power to you.
It's a bit more work but I've found filling the bowl with a squirt bottle and then starting the motor the way it was designed to start works for me - no stalling, no flooding, coughing and sputtering, and no running the starter for long periods of time (anyone who likes to listen to GTX's Chrysler reduction gear starter crank for 10 - 15 seconds is crazy).
And yes, both my Plymouth and Corvette carbs are too dry to fire quickly after a couple of days sitting - particularly in the summer months.
It's a bit more work but I've found filling the bowl with a squirt bottle and then starting the motor the way it was designed to start works for me - no stalling, no flooding, coughing and sputtering, and no running the starter for long periods of time (anyone who likes to listen to GTX's Chrysler reduction gear starter crank for 10 - 15 seconds is crazy).
And yes, both my Plymouth and Corvette carbs are too dry to fire quickly after a couple of days sitting - particularly in the summer months.
Thread Starter
3rd Gear
Joined: Nov 2016
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Welcome to the forum. With engine cold, remove the air cleaner and see if the butterfly closes when you trip the accelerator rod on the carb. The choke mechanism should close it with about an 1/8 gap or so. The choke tube only draws heated air when it’s running to speed up the choke spring to open the butterfly. There’s a small passage way in the carb and choke housing that can be clogged up with carbon that would slow down the choke opening after its running. How long have you had the car?
Carter's 63