1977 Long Cranking before start
Thread Starter
5th Gear
Joined: Nov 2013
Posts: 5
Likes: 1
From: Palm Beach Florida
1977 Long Cranking before start
I have a 1977 c3 original- In 2013 replaced tuneup parts , belts, hoses, tires, brakes.
I have one problem left.
If I let the car sit for several days- I must crank for 10 seconds before it starts. Runs great. I can stop- turn it off, and restart immediately.
In fuel injected cars- this is symptomatic of a check valve in the fuel pump. The fuel pump is original. I replaced the fuel filter. I am the original owner- so any work was done only to address problems. Original carburetor. Any advice would be appreciated. Jeff
I have one problem left.
If I let the car sit for several days- I must crank for 10 seconds before it starts. Runs great. I can stop- turn it off, and restart immediately.
In fuel injected cars- this is symptomatic of a check valve in the fuel pump. The fuel pump is original. I replaced the fuel filter. I am the original owner- so any work was done only to address problems. Original carburetor. Any advice would be appreciated. Jeff
Thread Starter
5th Gear
Joined: Nov 2013
Posts: 5
Likes: 1
From: Palm Beach Florida
Thanks for the feedback. I pump the gas pedal twice to set the choke. Then I crank the engine five seconds. I stop. Do not touch the gas pedal. and then crank for five seconds and it starts. Idle is 1500 RPM. If i drive around- and stop. Get back in the same day- turn the key- starts right away- this only happens after sitting for several days. I have has the car for many years- and when new- I do not recall this happening.
Thank you.
Thank you.
Drifting
Joined: Oct 2020
Posts: 1,566
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From: Wisconsin
Pretty normal for a cold start on a carbed car. Key on, once to the floor to set choke. Turn over 2-3 seconds and stop. Pump pedal 3-5 times and it should start almost immediately on the turn of the key.
When warm it should start with no accelerator interaction at all. Mine lights off with barely one revolution of the crankshaft when warm.
When warm it should start with no accelerator interaction at all. Mine lights off with barely one revolution of the crankshaft when warm.
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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Cruise-In VIII Veteran
I've had my 77 for many years. Had 2 different carbs on it over the years. Always started like that when sitting for a few days or longer. 10 seconds is nothing to be concerned about. I always did the two crank thing on mine when it had a carburetor and had been sitting. Normal.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
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From: New Braunfels Texas
Has the fuel filter been replaced recently? Stock filter has an anti-drainback valve on it. Has the carb been rebuilt? Stock Q-Jet has a "tower" style seat...a lot of aftermarket seats have a window machined 1/4" down......with a non check valve filter and this seat.....the bowl will drain considerably......
Jebby
Jebby
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Burning Brakes
Joined: Oct 2001
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From: TX
Jeff
My 69 starts exactly the same as yours. It has an untouched correct service Rochester put in around 1975. I don't believe there is a problem, but.......
I bet the accelerator pump is not at the top of its game. Reading some of Lars' info I gather a new pump will diminish the cranking time. I've been looking for an excuse to send my carb to Lars but it really runs well and I don't want to change anything just yet.
VS
My 69 starts exactly the same as yours. It has an untouched correct service Rochester put in around 1975. I don't believe there is a problem, but.......
I bet the accelerator pump is not at the top of its game. Reading some of Lars' info I gather a new pump will diminish the cranking time. I've been looking for an excuse to send my carb to Lars but it really runs well and I don't want to change anything just yet.
VS
Race Director
Joined: Mar 2017
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From: Virginia
Has the fuel filter been replaced recently? Stock filter has an anti-drainback valve on it. Has the carb been rebuilt? Stock Q-Jet has a "tower" style seat...a lot of aftermarket seats have a window machined 1/4" down......with a non check valve filter and this seat.....the bowl will drain considerably......
Jebby
Jebby
Putting in the proper fuel filter with a check valve reduced my start times noticeably. Both cars are (were) at about 10 seconds after siting for days.
Intermediate
Joined: Sep 2021
Posts: 38
Likes: 18
From: Texas
My 1980 with stock Q-Jet carb does the same thing.
Question for those mentioning the filter check valve: None of the options I see from various vendors (RockAuto, OReily, Autozone) mention having a check valve. Do some brands have it. and others don't? Or should it be standard on all filters but subject to fail over time? If the latter is true, longer crank times may be a good indication its time to change the filer.
Question for those mentioning the filter check valve: None of the options I see from various vendors (RockAuto, OReily, Autozone) mention having a check valve. Do some brands have it. and others don't? Or should it be standard on all filters but subject to fail over time? If the latter is true, longer crank times may be a good indication its time to change the filer.
Race Director
Joined: Mar 2017
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From: Virginia
I'd suspect that either of the currently available options at RockAuto have the check valve. The fuel filter that I removed did NOT have the black gasket built in, but whatever I used when I replaced it, did.
WIX 33052
or
GM GF471
If you want to be 100% sure, order from Cliff
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WIX 33052
or
GM GF471
If you want to be 100% sure, order from Cliff
https://cliffshighperformance.com/
Le Mans Master
Joined: Jan 2007
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From: Omaha NE
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When it's cold I crank the motor over until the oil gauge wakes up. Then I stop & give two squirts of gas.
Crank again & she fires right up. I've been doing it like this for the last 47 years...
Crank again & she fires right up. I've been doing it like this for the last 47 years...
Heel & Toe
Joined: May 2023
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From: Houston, TX
My 1973 does the same thing if I don't start it everyday. However, if I drive it every day, it fires-up in the morning much more quickly. My theory is that over the course of several days, the carburetor bowl either losses fuel to evaporation and/or the fuel line losses "prime". In other words, the fuel system needs to be refilled, to a certain extent. I've read this is much more of an issue with the ethanol containing pump gasoline we have available now.