Starting a cold engine
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Team Owner
Joined: Jan 2006
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From: Crossville TN
If the carb is working properly, one pump is all it should take. If it requires more than that, look for issues with the carb accelerator pump and/or the choke system. Ignition system problems can also be to blame for hard starts.
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Race Director
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From: SW Florida.
After it sits over night, take off the air filter hold the choke open and look in there while somebody pumps the gas. See if you see a squirt or not. Some older carbs will drain empty overnight. Some will boil all the fuel out. And hammerhead, that's the biggest link I ever saw. And it doesn't work.
Last edited by derekderek; May 10, 2019 at 08:42 AM.
Melting Slicks
Joined: Mar 2005
Posts: 2,093
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From: Midlothian VA
After it sits over night, take off the air filter hold the choke open and look in there while somebody pumps the gas. See if you see a squirt or not. Some older carbs will drain empty overnight. Some will boil all the fuel out. And hammerhead, that's the biggest link I ever saw. And it doesn't work.
The preview showed the pic but when I hit post WOW!
All fixed now.
Drifting
Joined: Nov 2013
Posts: 1,561
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From: Loud, Raw and Dangerous 1968 327 4S in Southern California
On mine when cold overnight...one time push to the floor to set the choke, then release and not give it any gas and it fires immediately up at fast idle. If it has been more than a few weeks it takes a bit longer to fire but no change in sequence. Hot it likes a bit of throttle held open with no pumping then it fires up after few seconds of starter. Each car is likely different due to carb, headers, ignition, condition, ect. setups so recommend trying all the suggested methods here and if none work well investigate further.
Edit: After reading all of the responses, I tried hot starting without pumping or depressing the gas pedal and it works just as well. Due to the engine cam installed, I have the idle set a bit higher than normal so that may have helped.
Redvette2
Edit: After reading all of the responses, I tried hot starting without pumping or depressing the gas pedal and it works just as well. Due to the engine cam installed, I have the idle set a bit higher than normal so that may have helped.
Redvette2
Last edited by Redvette2; May 15, 2019 at 09:23 AM. Reason: Updated information...
Burning Brakes
Joined: Jan 2007
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From: Lighthouse Point FL
No pumps. Pumping the gas is a good way to tear up your accelerator pump. On my 427, I ruined the accelerator pump Lars installed by pumping the gas before starting the car. The carb seems to evaporate the gas in the accelerator well and pumping the throttle in the dry well ruins the seal.
I turn the key and let the engine turn over for 5-10 seconds. This makes sure there is gas in the carb. I push the throttle down once to set the choke and then hit the key again. Car starts immediately on fast idle. It’s never cold here so a quick stab of the gas and the idle drops to where it should be without the choke. No need to pump a properly set up carb.
I turn the key and let the engine turn over for 5-10 seconds. This makes sure there is gas in the carb. I push the throttle down once to set the choke and then hit the key again. Car starts immediately on fast idle. It’s never cold here so a quick stab of the gas and the idle drops to where it should be without the choke. No need to pump a properly set up carb.
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No pumps. Pumping the gas is a good way to tear up your accelerator pump. On my 427, I ruined the accelerator pump Lars installed by pumping the gas before starting the car. The carb seems to evaporate the gas in the accelerator well and pumping the throttle in the dry well ruins the seal.
I turn the key and let the engine turn over for 5-10 seconds. This makes sure there is gas in the carb. I push the throttle down once to set the choke and then hit the key again. Car starts immediately on fast idle. It’s never cold here so a quick stab of the gas and the idle drops to where it should be without the choke. No need to pump a properly set up carb.
I turn the key and let the engine turn over for 5-10 seconds. This makes sure there is gas in the carb. I push the throttle down once to set the choke and then hit the key again. Car starts immediately on fast idle. It’s never cold here so a quick stab of the gas and the idle drops to where it should be without the choke. No need to pump a properly set up carb.
Le Mans Master
Joined: Dec 2007
Posts: 6,422
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From: McHenry Illinois
On mine, when cold, half a pump to set the choke, crank till it starts, runs on fast idle till warmed up. If it's been sitting a week or more, it just cranks longer before start. A warm engine, do not touch the accelerator, just hit the key and its running, any pumping when warm will flood it. This is how they are supposed to work and mostly did when new.
Team Owner
Joined: Jan 2006
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From: Crossville TN
According to the Owner's Manual, press accel pedal once to the floor with a cold engine; turn ignition to start until engine starts; when engine is running smoothly (on Fast Idle), idle speed can be reduced by lightly depressing accel pedal and slowly releasing (this drops choke from fast-idle stop).
For warm engine, depress accel pedal LIGHTLY (to set choke, but NOT activate accelerator pump), then crank to start.
For warm engine, depress accel pedal LIGHTLY (to set choke, but NOT activate accelerator pump), then crank to start.
Burning Brakes
Joined: Sep 2018
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With nearly any stock engine equipped with a Holley and Auto divorced choke - this is what I have done for 20+ years.
If it has been sitting a couple of weeks I pull of the aircleaner lid and fill the holley bowls through the vents with a squeeze bottle. then a quick squirt into the primary throttle bores.. fires right up immediately.
If it's a restart after recent drive - just hit the key.
Engine cold overnight. once to the floor to set the fast idle/choke. -
Less than a couple of weeks- three times and hit the key.
If it has been sitting a couple of weeks I pull of the aircleaner lid and fill the holley bowls through the vents with a squeeze bottle. then a quick squirt into the primary throttle bores.. fires right up immediately.
If it's a restart after recent drive - just hit the key.
Engine cold overnight. once to the floor to set the fast idle/choke. -
Less than a couple of weeks- three times and hit the key.
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