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I own a 1969 Chevelle SS396 with the 350 hp engine that runs very well. I live in a hot climate, it's usually 80 or 90 degrees year round. Whenever I start the car cold I have to crank 30-60 seconds while furiously pumping the gas pedal. Sometimes so long it starts to drain the (new) battery. Squirt a shot of starter fluid into the 4bbl and starts immediately. Anyone know a fix for this so I don't have to take off the air cleaner every time I want to go for a ride?
 

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I would start with fuel draining out of the carburetor while sitting. If it's a QJ, the main well leaks internally. If it's a Holley, they generally leak out onto the manifold. The question is if this is the case, why is it taking so long to fill the carb up, and, Does the choke work at all?
 

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Install electric fuel pump.

A carb isolator gasket or plate might help.

Either your fuel is boiling off, leaking or evaporating. The actual time between starts might answer what is the cause. Your float bowls are losing fuel between starts. A mechanical pump take a few seconds of turn over to refill the bowls. An electric pump will fill the bowls by waiting a few seconds with the ignition on before cranking. A properly functioning choke helps get engine started without a lot of accelerator pumping.
 

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How long had the car been sitting when this happens? Is the choke adjusted correctly?
 

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Modern gas evaporates rather quickly (the bowl will 'dry out' after a few days). The carb may be simply 'out of gas'. There may be nothing 'wrong'.

If the bowl is empty, the car needs to crank (to 'run' the mechanical fuel pump) to replace the 'lost' gas before it will start. Instead of pumping the gas pedal trying to start it, recommend one 'pump' to set the choke, repeat short (3 sec or so) bursts from the starter until it starts (3-6 bursts should suffice); do not touch the gas pedal. Let the system do its job. That process starts my car every time after it has sat for a few (4-5) days.

The first time I ran out of gas (1968?), I had to turn over the engine several times (to cycle the fuel pump) to pump the added gas from the tank to carb. The second time I ran out of gas (likely also in 1968?), I 'saved' a couple of ounces of gas to put directly into the carb; started right up. I rewarded myself with a beer.

If the car is 'doing' it everyday. It's not evaporation. But, as others have said, still may be related to the 'empty bowl'.

Pete
 

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Squirt a shot of starter fluid into the 4bbl and starts immediately

The only thing I will add is that you should throw the starter fluid in the trash. It will absolutely kill an engine if you are not careful. Gumout carb cleaner will start the engine just as well and wont hurt anything.
 

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Discussion Starter #7
The only thing I will add is that you should throw the starter fluid in the trash. It will absolutely kill an engine if you are not careful. Gumout carb cleaner will start the engine just as well and wont hurt anything.
YIKES thanks! It's a Carter. No doubt the gas is boiling off after each ride cause it's always 90 degrees here. I had this car in high school and while I can't remember having this same starting problem what I do remember is always keeping a mason jar with gasoline in it under the driver's seat. Not genius teenager. Thanks for the inputs.
 

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pump the gas pedal three times and crank. then hold the pedal down and crank
 

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Trivia:
Both of my 70s, LS-5/M-22 (one owner) and my FAKE SS454 Wgn. On both 70s, I have the cheap $35.00 Electric fuel pump mounted at the tank, With metal fuel filters before the pump. On a toggle switch.
Turn on the Elect. pump, When it quits " CLICKING ", Hit the key, One or two spins and it fires up. When I drive the Wagon EVERYDAY in the summer. I NEVER use the Elect. pump.
Also, If the Mech. pump craps out, Turn on the Electric and keep driving....:thumbsup:
Bob
 

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Might this engine have a stock Q-Jet intake manifold, and stock Q-Jet carb??? If so, there might be a serious issue in the selection of gasket between carb and manifold.

If the manifold is a Q-Jet, and a square flange carb has been subbed onto it, it might be a gasket and adapter issue.

Please advise if these paramters have been changed, or are as stock, and what was stock for that engine.
 

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Discussion Starter #11
Might this engine have a stock Q-Jet intake manifold, and stock Q-Jet carb??? If so, there might be a serious issue in the selection of gasket between carb and manifold.

If the manifold is a Q-Jet, and a square flange carb has been subbed onto it, it might be a gasket and adapter issue.

Please advise if these paramters have been changed, or are as stock, and what was stock for that engine.
I have no idea. This car was built by founding member Alan F, if he is still around maybe he would opine?
 

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I have no idea. This car was built by founding member Alan F, if he is still around maybe he would opine?
It is a stock manifold, stock carburetor with stock gaskets. The well plugs were sealed with epoxy. Because I drove the car very sparingly, I always assumed the bowl was empty after sitting for extended periods. There was a lot of attention paid to setting up the choke to work correctly but that’s where I would start to look. I remember it being very cold blooded and needed the choke desperately.

Knowing that it was dry when I went to start it, I did the same just cranked on it until it caught. It was harder to keep running before I got the choke where I wanted it than to get it running. I’m suspecting the choke. If it were a Holley with giant squirters you can overcome the lack of a choke.
 

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"It is a stock manifold, stock carburetor with stock gaskets"

OK, well.....JUST WHICH "STOCK" MANIFOLD AND CARB SET??????
 

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Since its so hot there do you even need a choke? Try disconnecting it by removing the flapper, that way you will have fast idle.. Then see how it starts..

On my fair weather cars with performance quadrajets that had the air horns epoxy smoothed with the choke flap removed, I used to just use a AC solenoid that bumped the idle up to 900, I'd just flip that on and fire it up, they started every time no trouble..
 

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When I owned it, it was a 1969 L34 JC Coded 396 with the 3955272 block (396/350HP). The correct intake manifold is oval port cast iron 3931067 with the 7029215 4 speed Quadrajet.
 

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The tank had the factory vent loop installed.
 

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You definitely DO NOT need or want an electric fuel pump, and definitely DO NOT need or want to disable the choke. These cars run great in stock configuration, and IMHO run best in stock configuration.

When tuned and maintained properly, you pump the gas pedal ONCE to the floor on a cold engine to set the choke and deliver one squirt of fuel to the engine. Car will fire instantly when you twist the key. If the above process doesn't work, you are out of tune, choke is not adjusted correctly, or fuel is leaking down as described and your carb needs a repair. Fix it right.

As far as modern fuels evaporating out of the carb, I suppose that's possible. The best solution is don't let the car sit too long without firing the engine and letting it run a little bit.
 
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Discussion Starter #20
Tried several different approaches. When I pump the gas pedal one time only, it immediately fires then immediately dies. Then it's back to cranking while furiously pumping the gas for 15-20 seconds and it grudgingly starts. After that it will easily start all day until the next time the engine's cold. I guess I could go with this but I worry about damaging the starter or battery.
 
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