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-   -   Long crank after parked for a week (https://67-72chevytrucks.com/vboard/showthread.php?t=827061)

Mryan 10-21-2021 11:17 AM

Long crank after parked for a week
 
I have a 1971 with the original in cab fuel tank and a transplanted 454. If this truck sits for a week or more it takes a long time to start, It has a new fuel pump and filter. Is there a check valve that should stop the fuel from completely draining the line? If I drive it the following day or two it starts right up. Thoughts?

BigBird05 10-21-2021 11:25 AM

Re: Long crank after parked for a week
 
After letting sit for a week take the air cleaner off, pump the throttle a couple of times and see if any gas is squirting into the venturis. If not you carb is leaking down.

Palf70Step 10-21-2021 11:39 AM

Re: Long crank after parked for a week
 
:agree: All of mine with quadrajets or edelbrocks seem to have that issue. Not as much with the Holley.

Mryan 10-21-2021 11:54 AM

Re: Long crank after parked for a week
 
Forgot to add it is an Edelbrock carb...

HO455 10-21-2021 02:17 PM

Re: Long crank after parked for a week
 
When you say a long crank how long are we talking about?

Today's alcohol infested fuel will evaporate faster and more completely than the fuel of yesterday. This can empty the float bowl of combustible liquid causing the condition you are experiencing.

There is no need for check valves. The fuel enters those carburetors from the top of the float bowl so the fuel cannot drain out.

Old rubber hoses on the suction side of the fuel pump can cause it to suck air and not pull fuel properly making for longer cranking to get fuel to the carburetor. The small air leaks will allow the fuel in the line to siphon back into the fuel tank when the truck is shut off. Making even more work for the pump on start up.

I agree with BigBird05 as to the first place to start looking. Then I recommend a careful inspection of the fuel lines. If all is good then pulling the sender and inspecting the lines for damage and making sure the sock isn't plugged.

Good luck and please keep us updated.

sick472 10-21-2021 02:26 PM

Re: Long crank after parked for a week
 
I have 3 "sitters". One has an Edelbrock, one QuadraJet, & One Holley. They will all take 10 seconds (or more) of cranking to fire-up after sitting for a few days. Two of them are manual chokes and tend to fire-up quicker if the choke is pulled where the QuadraJet (with a broken choke) really likes to have some gas poured down it to speed things up.

I have heard of someone on here putting an electric fuel pump in the line (alone with the mechanical pump, I think) to assist with this occurrence, but I have not wrapped my head around how to do it myself.

Mryan 10-21-2021 02:41 PM

Re: Long crank after parked for a week
 
Length of cranking time could be up to a minute, the fuel lines are new and not leaking from the fuel pump to carb. I have yet to carefully look at the lines from tank to pump but do not have a raw fuel smell or anything on the floor after parked. Additionally the oil doesn't smell like fuel. I have been suspect of the carb but don't have any proof.

El Dorado Jim 10-21-2021 04:15 PM

Re: Long crank after parked for a week
 
I have an edelbrock on mine, i added an inline electric fuel pump underneath the truck,switch under dash, turn on the pump for a few seconds and the truck fires right up, then turn the switch off....

57taskforce 10-21-2021 10:36 PM

Re: Long crank after parked for a week
 
My 1406 Eddie can take 30 seconds or more of cranking if it’s been sitting more than a few days. I think part of the problem for me is the typical heat soak that boils the fuel in the Eddie’s bowls. If most of the fuel boils out after cutting it off from a long drive then there’s not going to be much fuel remaining in the bowls a week later. I know for a fact mine boils the fuel when it gets good and hot and you cut it off.

Richard 10-22-2021 12:58 AM

Re: Long crank after parked for a week
 
There is a filter with a check valve. That is the type original to the carb. A lot of the replacement ones I have seen do not have the valve.

68Gold/white 10-22-2021 01:25 AM

Re: Long crank after parked for a week
 
To start a long sitting car:
Turn the engine over, WITHOUT PUMPING THE THROTTLE PEDAL, even once. Turn it over for about 10-15 seconds. This gets gas TO THE CARB.

Then pump the gas pedal one or twice, to set the choke, then spin the engine, see if it hits. If not, spin the engine over, just a little more (to get more gas to the carb) it should start now.

Sometimes the engine will hit when you are doing the initial 15 second spin, if so, it’s ready to start.

I’ve noticed that (sometimes) if you just jump in a long sitting vehicle, by furiously pumping the throttle pedal and spinning the engine, you can flood the engine, sometimes easily....

Lethal Tendencies 10-22-2021 07:08 AM

Re: Long crank after parked for a week
 
Electric or manual choke ?

Davidf 10-22-2021 09:28 AM

Re: Long crank after parked for a week
 
Quote:

Originally Posted by sick472 (Post 8986601)
I have 3 "sitters". One has an Edelbrock, one QuadraJet, & One Holley. They will all take 10 seconds (or more) of cranking to fire-up after sitting for a few days. Two of them are manual chokes and tend to fire-up quicker if the choke is pulled where the QuadraJet (with a broken choke) really likes to have some gas poured down it to speed things up.

I have heard of someone on here putting an electric fuel pump in the line (alone with the mechanical pump, I think) to assist with this occurrence, but I have not wrapped my head around how to do it myself.

Carbs suck! So, I went the LS route and will never look back.

But, my 72 240z behaves like this. If it sits more than a couple of days, it was very hard to start. So, added an electric pump. Datsun was kind enough to wire every car for an electric pump near the fuel tank. I also added a electric fuel pump controller under the dash. The controller shuts of the fuel pump if there is no tachometer signal present. So, my solution was to not connect the controller to the tank. Without the signal, upon turning on the ignition, the controller will run the electric pump for about 2 seconds...this is long enough to prime the carburetors and make for easier starting. Once the engine fires, the mechanical fuel pump takes over (and I don't have to listen to the electric pump running). Could be an option.

Bonus: If the mechanical pump dies, all i have to do is connect the tach signal to the pump controller and I am on my way.


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