Idling problem
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
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From: Bay Area CA
Idling problem
My 69 starts right up in the first cranking, but it would not idle without slightly stepping on the gas. After a few minutes of waiting and slight pumping on the gas pedal would make it start idling smooth.
What would I have to do to get it start idling right after starting the car?
I have a holly carb on a 502 motor.
What would I have to do to get it start idling right after starting the car?
I have a holly carb on a 502 motor.
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
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From: Bay Area CA
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No, None of my cars have the choke set up. You can't expect it to idle when it's cold without a choke though. I keep my foot on the accelerator and keep the RPM's up to about 1300 until the engine temp reaches about 100 degrees. It will idle then and you can drive it.
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
No, None of my cars have the choke set up. You can't expect it to idle when it's cold without a choke though. I keep my foot on the accelerator and keep the RPM's up to about 1300 until the engine temp reaches about 100 degrees. It will idle then and you can drive it.
You don't HAVE to have a choke, but you must baby it when it's cold. That being said, if you DO have a choke it must be set up or adjusted properly for it to keep the engine running when it's below operating temps.I have heard of guys using an A/C high idle solenoid on a switch to kick up the idle for when it's cold so you don't have to keep your foot in the gas until it warms up.
Le Mans Master
Joined: Jan 2006
Posts: 8,319
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From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
No, None of my cars have the choke set up. You can't expect it to idle when it's cold without a choke though. I keep my foot on the accelerator and keep the RPM's up to about 1300 until the engine temp reaches about 100 degrees. It will idle then and you can drive it.
the second/ next question is why, is it just not connected, or not functioning, or not there at all?
e.g I have a divorced choke, but when I put on the brodix heads, there is no water passage to allow coolant to flow through the intake so my choke though present does not function properly, so I have to do the throttle thing till it warms up.
find out why your choke is not working and maybe you can fix it. is it an electric choke or thermal? take a pic of the carb if you can
cheers
tim
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
Likes: 1
From: Bay Area CA
the second/ next question is why, is it just not connected, or not functioning, or not there at all?
e.g I have a divorced choke, but when I put on the brodix heads, there is no water passage to allow coolant to flow through the intake so my choke though present does not function properly, so I have to do the throttle thing till it warms up.
find out why your choke is not working and maybe you can fix it. is it an electric choke or thermal? take a pic of the carb if you can
cheers
tim
Team Owner
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From: Sorrento Italy
[QUOTE=Durango_boy;1563773847 .............but you must baby it when it's cold.........
DB...this is exactly what i always do with all my engines:o ...then, when they're pretty warm, it's their turn to baby ME!
DB...this is exactly what i always do with all my engines:o ...then, when they're pretty warm, it's their turn to baby ME!
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Le Mans Master
Joined: Jan 2006
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From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
If thats the case then you can either keep feathering the throttle till its warm, Try DDB's solution ( neat trick BTW), or mod or replace the car.
No offense, but are you good with mechanical stuff? just curious so we know what level of assistance you might need.
Pic of the carb would still be nice just cause we love pics of Big Blocks
Last edited by sweethence; Jan 24, 2008 at 10:44 AM.
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
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From: Bay Area CA
If thats the case then you can either keep feathering the throttle till its warm, Try DDB's solution ( neat trick BTW), or mod or replace the car.
No offense, but are you good with mechanical stuff? just curious so we know what level of assistance you might need.
Pic of the carb would still be nice just cause we love pics of Big Blocks
No offense, but are you good with mechanical stuff? just curious so we know what level of assistance you might need.
Pic of the carb would still be nice just cause we love pics of Big Blocks
I will post a pic of the carb tonignt with the air cleaner off.
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
Likes: 1
From: Bay Area CA
I am not sure why that plastic tie is for in picture 2.
The carb sprays gas if I press on a little lever on the side. Isn't it the choke? So it does have a choke?
Last edited by rajsid; Jan 25, 2008 at 12:34 AM.
Race Director
Joined: Nov 1999
Posts: 10,643
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From: Foxfield CO 1970 Convertible
Well, you've got a choke. It's the single large tallest black butterfly valve (flap) in the pix. It looks like that plastic tie might be in there to tie the choke open. Sounds like some previous owner didn't want to fix the choke and would rather put up with fussing around with it while it was cold. I suspect if you take off that tie, the choke will flap around and give you trouble. It might have been done if the 502 has a manifold that doesn't have a heat riser mechanism for controlling the choke. You might be able to get an electric to fit, or you could add a choke cable like my old sports car and my current lawn mower have.
Either way, having a working choke will really clear up that rough time right after starting...
PS - the squirter thing is an accelerator pump for when you mash the throttle as you pass Mustangs.
Either way, having a working choke will really clear up that rough time right after starting...
PS - the squirter thing is an accelerator pump for when you mash the throttle as you pass Mustangs.
Last edited by Z-man; Jan 25, 2008 at 01:52 AM.
Le Mans Master
Joined: Jan 2006
Posts: 8,319
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From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
Well, you've got a choke. It's the single large tallest black butterfly valve (flap) in the pix. It looks like that plastic tie might be in there to tie the choke open. Sounds like some previous owner didn't want to fix the choke and would rather put up with fussing around with it while it was cold. I suspect if you take off that tie, the choke will flap around and give you trouble. It might have been done if the 502 has a manifold that doesn't have a heat riser mechanism for controlling the choke. You might be able to get an electric to fit, or you could add a choke cable like my old sports car and my current lawn mower have.
Either way, having a working choke will really clear up that rough time right after starting...
PS - the squirter thing is an accelerator pump for when you mash the throttle as you pass Mustangs.
Either way, having a working choke will really clear up that rough time right after starting...
PS - the squirter thing is an accelerator pump for when you mash the throttle as you pass Mustangs.
look closely, the choke you have is set up for a manual choke cable right now, probably why is zip tied off like that. the round thing with the set screw is where the cable would go. but it still a basic holley carb, and can be easily converted to an electric choke
cheers
tim
Last edited by sweethence; Jan 25, 2008 at 07:41 AM.
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
Likes: 1
From: Bay Area CA
You guys are the greatest 
Yes, the manifold does not have a heat riser mechanism.
How does an electric choke work? Will it turn on automatically everytime you start the car?
I actually love the lawn mower idea
I guess adding a choke cable to the existing manual choke would be easier. Are there any cable kits available?
Yes, the manifold does not have a heat riser mechanism.
How does an electric choke work? Will it turn on automatically everytime you start the car?
I actually love the lawn mower idea
I guess adding a choke cable to the existing manual choke would be easier. Are there any cable kits available?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
You guys are the greatest
Yes, the manifold does not have a heat riser mechanism.
How does an electric choke work? Will it turn on automatically everytime you start the car?
I actually love the lawn mower idea
I guess adding a choke cable to the existing manual choke would be easier. Are there any cable kits available?
Yes, the manifold does not have a heat riser mechanism.
How does an electric choke work? Will it turn on automatically everytime you start the car?
I actually love the lawn mower idea
I guess adding a choke cable to the existing manual choke would be easier. Are there any cable kits available?
The electric choke is just a heat sensitive wound spring that contracts and expands based on temperature. It gets 12V switched when the engine is running where it is already set to cold start. As the coil warms up from the current, the spring moved the choke buttery fly for hot engine operation.
You would have more control using a manual choke cable but you would have to mount the push/pull switch somewhere inside, and run a cable to it.
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,483
Likes: 1
From: Bay Area CA
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Race Director
Joined: Nov 1999
Posts: 10,643
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From: Foxfield CO 1970 Convertible