Hard starting.

[Squareforceone]

My truck has always been a bit hard to start it gets really bad during the winter. i have messed with the choke some many times and i'm fairly confident that it's adjusted right but it still seems to be hard to start at first usually have to pump it and then give it some gas on the first start up of the day. I'm just curious what other things could cause this besides the choke.. fuel pump maybe?

[Squareforceone]

ttt

[pwradder]

is it a holley or rochester? is it starting okay then idling too low or does it take forever to fire?

[JellyBeanDriver]

subscribing - I have similar problems with a QJ carb'd 86' C30 crewcab dually, 454.

[motornut]

hows the fuels lines and rubber bits,sending unit
remove the line from the pump to the carb ,clean it out
hows the fuel filters

[wilkin250r]

Without being there in person, it's not easy to determine what is "hard starting" or just normal starting for cold weather, so let's try a little background info to start.

In order for fuel to burn, it must vaporize. That's much more difficult in cold weather than warm weather, for obvious reasons. It's also much more difficult for CARBURETED vehicles because of the way carburetors work. You're just using moving air to pull fuel from the carb bowl, it's not a really powerful force. As a result, the fuel passages in a carburetor are fairly large, compared to fuel injection, and result in LARGE droplets of fuel that don't want to vaporize easily, and certainly don't want to vaporize when they hit cold intake passages.

So the solution is to dump LOTS of fuel into the intake, either by using the choke or by pumping the gas several times to get the accelerator pump to inject a bunch of fuel into the intake. With such an over-abundance of fuel, you'll get some of it to vaporize and allow your car to start.

So my first question is: Are you pumping the gas before you try to start? How many times?

[Squareforceone]

quadrajet fairly new fuel filter have to pump several times like the choke isn't working but it is... and i know how a carb works and that they are harder to start than fuel injection and yes i'm pumping it before hand a lot....

[hotstuff]

Check the choke linage for freeness ,while you have the air cleaner off ,check the accelerator pump shot and choke flap gap

[wilkin250r]

Agreed, the next thing I would investigate would be the accelerator pump.

[pwradder]

x3 on the accel. pump, you can check it by holding the choke flap open and looking down the primary side with a light-you should see a strong shot of fuel when you pump the gas (engine off of course).

[86c20]

One thing to think about is the lift pump on the motor if its not holding fuel in the line they are gard starting. Try cranking it for 5 sec then give it a pump on too to set the chock and add fuel then start it. Doing that will tell u if it is lack of fuel in the carb
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[JellyBeanDriver]

Originally Posted by 86c20

One thing to think about is the lift pump on the motor if its not holding fuel in the line they are gard starting. Try cranking it for 5 sec then give it a pump on too to set the chock and add fuel then start it. Doing that will tell u if it is lack of fuel in the carb
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Is this common? (the mechanical fuel pump leaking back?)