Truck shuts off after starting...

[Jayschevy]

I have a 71 with a 350, HEI and Holley 3310-4 carburetor. Lately when I go to start my truck it starts up fine but stalls and cuts off after a few seconds. I have to keep my feet on the gas pedal to keep it running. After about 30 seconds or so it stays running. The only thing I've noticed is that the plate on top of my carburetor is always open. Could this be the reason why I'm shutting off and why is it not opening and closing? Any suggestions?
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[71K20chevy]

It's because the choke (the plate that won't open and close) is stuck open. The choke puts more fuel in the engine to aid in cold starts (just whenever engine is below normal operating temp.).


It almost looks like the choke is mounted to the secondaries?

[Jayschevy]

What could cause the plate to stay open? How can I fix it?

[GASoline71]

The choke has been wired open by the PO. You can get a universal "hand choke" cable from the local parts store and install it. Then you can open or close it by hand. You can also get a kit from Holley to convert it to an electric choke.

I have completely removed every single choke from every single Holley carb I've ever bolted to an engine. Just gotta pump the gas a few times and feather the throttle for about 90 seconds until the vehicle will idle.

But if you live where it gets really cold... you might wanna opt for a choke that works.

Gary

[Jayschevy]

You may be right about it being wired open by the PO. But that doesn't explain why it's just starting to stall now when starting. I've had the truck 4 months and it's now only start doing this.

[GASoline71]

Because it's getting colder outside. The colder it gets the more fuel and less air required to start the vehicle. That's why a choke flap closes during cold starts. To restrict airflow, but not copletely block it off.

Gary

[midniteblues]

you could also get a cable from any place that sells lawn tractor parts ie ace,tractor supply,true value,and just about any hardware store I find the cables at these places are usually cheaper than auto stores just make sure you get one long enough. they are usually cheap no matter where you go i'm just sayin

[Jayschevy]

Originally Posted by GASoline71

Because it's getting colder outside. The colder it gets the more fuel and less air required to start the vehicle. That's why a choke flap closes during cold starts. To restrict airflow, but not copletely block it off.

Gary

Well at least now I know the carburetor is acting normal and not stuck or need adjustment. Guess I just gotta get use to giving it more gas to keep it running.

Also, what is the advantage of keeping it open all the time compared to having it open and close normally?

[GASoline71]

No restriction during WOT. It's why I usually mill the choke horn off and blend the inlet too.

Street/strip kinda thing.

Gary

[Jayschevy]

Is it possible to get the choke to work right again without buying a manual choke or electric choke? How do I get the choke to work like it is suppose to?

[67ChevyRedneck]

Buy a rebuild kit. There's a spring inside of the choke, it could be bad. The kit should have instructions on how to adjust it as well.

Personally, I love electronic chokes. I have an edelbrock 1406, 2 pumps when she's cold and she fires and fast idols for a bit, then backs off. No stalling. When she's warm I can turn it off and start it back up on the first key hit every time.

[geezer#99]

Originally Posted by Jayschevy

Is it possible to get the choke to work right again without buying a manual choke or electric choke? How do I get the choke to work like it is suppose to?

If you want it to work like it is set up now you need a choke cable. If you want to put an electric choke on it you need to buy the complete kit from Holley and convert it. The manual linkage needs to be removed and the electric linkage installed.
Easier to hook up a choke cable.
And for the comment about a spring inside the choke. There isn't one in the manual choke set up.

[Secret Squirrel]

Agreed it is probably the choke causing a hard start, however I had the same symptoms on my truck with an Edlebrock carb. It would start cold and then shut down once it warmed up.

Turns out when the bowl would fill up with fuel the floats would rise to cut of the flow of fuel (as they were designed to do), but the tapered valved would then stick closed due to a lot of dirt in the screens and the truck would run the bowl dry then die.

Over time they would eventually release allowing the truck to start again, but as the truck warmed up (i.e the bowl became full again) the fuel would get cut off. Not sure how much different your carb is to an Edlebrock, maybe this will help someone in the future?