Cold Start Issues
Burning Brakes
Joined: Oct 2012
Posts: 847
Likes: 359
From: Philo IL
I use a squeeze bottle from a chem lab supply store...
Note the stopper I put in the end of the tube to keep gas from evaporating in the bottle. I never have to use this if the cars sit for less than 2-3 weeks. They start right up now. Over winter if they sit for longer periods I use it to fill the float bowl via the front vent tube.
Thomas
Note the stopper I put in the end of the tube to keep gas from evaporating in the bottle. I never have to use this if the cars sit for less than 2-3 weeks. They start right up now. Over winter if they sit for longer periods I use it to fill the float bowl via the front vent tube.
Thomas
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
The first-generation Pertronix Ignitor 1's all reguired 3-5 seconds of "charge time" after turning the key "on", before turning it to "start", or the starter would just crank and crank and the engine wouldn't fire. 
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,145
Army
I had a couple of them in my first generation Mustangs and don't remember doing that at all...
I'll have to see if I have my old instructions for that early conversion...
Anyway I doubt that's the OPs problem as after 10 minutes the car apparently starts up fine, presumably using the same technique as used during the 'cold start'...
I'll have to see if I have my old instructions for that early conversion...
Anyway I doubt that's the OPs problem as after 10 minutes the car apparently starts up fine, presumably using the same technique as used during the 'cold start'...
Last edited by Frankie the Fink; Jun 11, 2015 at 09:48 PM.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
On the other hand, I found that if I let my car with an AFB sit idle for a week or so, the float bowl will go dry and it's necessary to crank the engine maybe five seconds to put gas in the float bowl. Stop cranking, pump the gas 2-3 times and hit the key and it starts. WCFB carbs don't act like this in my garage. I haven't fired a Holley up in a long time so don't know about them.
Just guessing, the OP's carb is going dry from sitting and needs to be refilled so it will start. It's easy to check. Before cranking, just look down the carb throat while you open/close the throttle and see if it's squirting gas or maybe just a little bit of gas. Either will make the car start cold.
The choke doesn't really have anything to do with starting the engine. It helps keep it running AFTER it starts.
Last edited by MikeM; Jun 12, 2015 at 08:20 AM.
Safety Car
Joined: May 2014
Posts: 3,783
Likes: 655
Mike,
I have to disagree with your last statement about the purpose of the choke when starting a cold engine.
It's true the choke provides the engine with a richer then normal A/F ratio after the engine starts but while cranking, the completely closed choke blade helps create a low pressure area around the booster venturi and fuel is drawn down into the engine to aid in starting.
After the engine starts and the choke pull off opens the choke it's manifold vacuum that pulls fuel into the engine from the idle circuit.
I have to disagree with your last statement about the purpose of the choke when starting a cold engine.
It's true the choke provides the engine with a richer then normal A/F ratio after the engine starts but while cranking, the completely closed choke blade helps create a low pressure area around the booster venturi and fuel is drawn down into the engine to aid in starting.
After the engine starts and the choke pull off opens the choke it's manifold vacuum that pulls fuel into the engine from the idle circuit.
Drifting
Joined: Nov 2007
Posts: 1,711
Likes: 179
From: Hightstown NJ
Mike,
I have to disagree with your last statement about the purpose of the choke when starting a cold engine.
It's true the choke provides the engine with a richer then normal A/F ratio after the engine starts but while cranking, the completely closed choke blade helps create a low pressure area around the booster venturi and fuel is drawn down into the engine to aid in starting.
After the engine starts and the choke pull off opens the choke it's manifold vacuum that pulls fuel into the engine from the idle circuit.
I have to disagree with your last statement about the purpose of the choke when starting a cold engine.
It's true the choke provides the engine with a richer then normal A/F ratio after the engine starts but while cranking, the completely closed choke blade helps create a low pressure area around the booster venturi and fuel is drawn down into the engine to aid in starting.
After the engine starts and the choke pull off opens the choke it's manifold vacuum that pulls fuel into the engine from the idle circuit.
Verne
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
This thread was about the engine not even firing or even trying to start. Thus, my comment and I think my comment pertains to that situation that the cold engine won't even hit. I don't believe that problem is related to the choke but rather a dry float bowl or inop accelerator pump. If the accelerator pump doesn't work on a really cold engine, you may not get it started whether the choke works or not. You agree?
I ran carburetors for decades without a choke and our winters get really cold here so I have a rough idea how they work.
Last edited by MikeM; Jun 12, 2015 at 05:49 PM.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
You're talking 1500-1700 rpm and the OP can't even get the engine to hit, let alone start so the main metering circuit has nothing to do with it. You guys are describing conditions AFTER the engine starts and runs. Not before.
You're are confusing apples with oranges.
Last edited by MikeM; Jun 12, 2015 at 05:54 PM.
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Brett Foote
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Safety Car
Joined: May 2014
Posts: 3,783
Likes: 655
Thanks. I know that. My statement was referring to lighting the engine off initially which I stated. Priming the carb with a few shots of gasoline into the manifold with the accelerator pump, give it a few seconds to vaporize and then you have a mixture more than rich enough to fire the engine and keep it running at least momentarily.
This thread was about the engine not even firing or even trying to start. Thus, my comment and I think my comment pertains to that situation that the cold engine won't even hit. I don't believe that problem is related to the choke but rather a dry float bowl or inop accelerator pump. If the accelerator pump doesn't work on a really cold engine, you may not get it started whether the choke works or not. You agree?
I ran carburetors for decades without a choke and our winters get really cold here so I have a rough idea how they work.
This thread was about the engine not even firing or even trying to start. Thus, my comment and I think my comment pertains to that situation that the cold engine won't even hit. I don't believe that problem is related to the choke but rather a dry float bowl or inop accelerator pump. If the accelerator pump doesn't work on a really cold engine, you may not get it started whether the choke works or not. You agree?
I ran carburetors for decades without a choke and our winters get really cold here so I have a rough idea how they work.
Mike,
I agree that the accelerator pump shot is paramount to starting a cold engine, and probably contributes more to cold starting than the other circuits because the operator can manually flood the engine with fuel. The carburetor was not engineered to be used that way as all the circuits are ment to work together and overlap each other.
I also agree that the issue at hand is a dry float bowl, at least that's where I would start, it's a very easy thing to test.
If I had to wait to start my car because of a Petronic's ignition I would go back to points, the Breakerless SE switch in my 67 is never a problem and if it ever is I will go back to points.
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,145
Army
I contacted Pertronix tech support on the 'wait to start' issue for the Ignitor I yesterday. They said there has never been any special start procedure for any version of the Pertronix. I certainly don't remember doing anything different when I began using them WAY back...
I can post the email from them but I doubt its necessary.
I can post the email from them but I doubt its necessary.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
Mike,
I agree that the accelerator pump shot is paramount to starting a cold engine, and probably contributes more to cold starting than the other circuits because the operator can manually flood the engine with fuel. The carburetor was not engineered to be used that way as all the circuits are ment to work together and overlap each other.
I also agree that the issue at hand is a dry float bowl, at least that's where I would start, it's a very easy thing to test.
If I had to wait to start my car because of a Petronic's ignition I would go back to points, the Breakerless SE switch in my 67 is never a problem and if it ever is I will go back to points.
I agree that the accelerator pump shot is paramount to starting a cold engine, and probably contributes more to cold starting than the other circuits because the operator can manually flood the engine with fuel. The carburetor was not engineered to be used that way as all the circuits are ment to work together and overlap each other.
I also agree that the issue at hand is a dry float bowl, at least that's where I would start, it's a very easy thing to test.
If I had to wait to start my car because of a Petronic's ignition I would go back to points, the Breakerless SE switch in my 67 is never a problem and if it ever is I will go back to points.
In the really old days, before accelerator pumps, the only way you could prime the engine was either pulling the choke out tight(like you said) or prime it manually with a squirt bottle. In that case, the choke was instrumental in starting the engine along with keeping it running after it started.
Instructor
Joined: Jun 2014
Posts: 124
Likes: 5
From: Elizabeth Colorado
start isssues
I have read all the comments on this post and have the same problems with starting. Pump the accelerator many times and cranks several times before my 61 will start. I too have a old Pentronix ignition system. I tried the "turn the key on for 5 sec pump the accelerator once then start" it fires right up with no cranking and pumping the accelerator. Got to be something with that ignition system. I wonder if it means that the ignition module if failing? Just a thought!
Intermediate
Joined: Jun 2020
Posts: 35
Likes: 1
Same issue with an Edelbrock
I have a base 300 hp in my “new to me” ‘67. The prior owner swapped to a Edelbrock carb and wired the choke open as he (and now I live in hot climates (Texas and now FLA)).He also installed a Pertronix, a flame thrower coil and MSD spark plug wires. Engine was rebuilt recently and was modified to take unleaded 93.
Even on overnight cold starts after trying multiple approach’s including leaving the ignition “On” for 5-10 seconds it just cranks and I have to put in 2-3 ounces of fuel into the carb which brings it to life.
when warm, it starts without even touching the gas pedal.
Does the Edelbrock/open choke change any of the prior suggested approaches?
Even on overnight cold starts after trying multiple approach’s including leaving the ignition “On” for 5-10 seconds it just cranks and I have to put in 2-3 ounces of fuel into the carb which brings it to life.
when warm, it starts without even touching the gas pedal.
Does the Edelbrock/open choke change any of the prior suggested approaches?
Le Mans Master
Joined: Feb 2012
Posts: 5,361
Likes: 2,872
From: Western Massachusetts
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I have a base 300 hp in my “new to me” ‘67. The prior owner swapped to a Edelbrock carb and wired the choke open as he (and now I live in hot climates (Texas and now FLA)).He also installed a Pertronix, a flame thrower coil and MSD spark plug wires. Engine was rebuilt recently and was modified to take unleaded 93.
Even on overnight cold starts after trying multiple approach’s including leaving the ignition “On” for 5-10 seconds it just cranks and I have to put in 2-3 ounces of fuel into the carb which brings it to life.
when warm, it starts without even touching the gas pedal.
Does the Edelbrock/open choke change any of the prior suggested approaches?
Even on overnight cold starts after trying multiple approach’s including leaving the ignition “On” for 5-10 seconds it just cranks and I have to put in 2-3 ounces of fuel into the carb which brings it to life.
when warm, it starts without even touching the gas pedal.
Does the Edelbrock/open choke change any of the prior suggested approaches?
Its a MUCH better idea to start a new thread with your problem than piggyback a 10 year old thread. Many of us here are on the edge of our chair ready to answer your question.
Dan
Racer
Joined: Nov 2017
Posts: 253
Likes: 140
From: Edinburg, New York
The only time I have a cold starting issue is when I don't run the car for more than 4 or 5 days. If it's less than that, two pumps and it starts pretty quick..
You have two choices when it's sat a long time:
1. wait for the fuel pump to fill the carb bowls because the gas has evaporated (Carter AFB's have huge vent tubes that make this happen fast)
What I do is pump the gas pedal twice, crank for 7 seconds....pump twice again, crank for 5 seconds..pump once and crank it usually fires.
2. Use a primer bottle to put about 2 ounces in the bowls through the vents, put the air cleaner cover back on, pump twice and crank.. it fires right up.
I'm not sure which method is easier on the engine for oil pressure building..I don't think it matters too much for most of us that don't much a ton of mileage on our cars.
You have two choices when it's sat a long time:
1. wait for the fuel pump to fill the carb bowls because the gas has evaporated (Carter AFB's have huge vent tubes that make this happen fast)
What I do is pump the gas pedal twice, crank for 7 seconds....pump twice again, crank for 5 seconds..pump once and crank it usually fires.
2. Use a primer bottle to put about 2 ounces in the bowls through the vents, put the air cleaner cover back on, pump twice and crank.. it fires right up.
I'm not sure which method is easier on the engine for oil pressure building..I don't think it matters too much for most of us that don't much a ton of mileage on our cars.