Captain_Kaboom

but at least I figured out why I have problems starting and accelerating. My Q-Jet primary is stuck open and my secondary is stuck closed! Grrrr Beautiful ride home on a glorious Friday afternoon spoiled..

Anyone have good pics of a functional Q-jet? The arm that opens the secondaries feels really loose like it is missing something. So bad I can't even see how it is supposed to function.

Beer helps ease the pain.

Greg

LiveandLetDrive

stuck open? :skep: Are you talking about the flaps on top? e.g. the choke. Or do you mean the throttle plates are actually stuck open??

-Chris

Captain_Kaboom

Yep, choke appears to be stuck open, secondaries don't open. The arm that move them is really loose...

LAvetteman

Lars can really bring a carburator back to life. You should give him a shout.

LiveandLetDrive

Perhaps yours is different than mine (is your carb non-stock?) but there is no "arm" that opens the secondaries. If it is connected to a little vacuum diaphragm on the passenger side of the carb, that is the "secondary lockout" that engages when the engine is on, keeping the secondaries from sucking air in a cold engine. The secondaries are vacuum-operated internally in the carb. Correct me if I'm wrong on this, that's how I've understood it.

The secondaries shouldn't open while revving in place, they only open under high-load conditions, like going to WOT at speed. Also, the choke is usually open when the engine is off after being warm, or while it's on and heated up. If it starts cold with it open, just adjust the choke housing cover (loosen 3 screws) until the choke has a 1/4" opening when cold. Hope that solves your problems, otherwise, wait for somebody who knows their stuff to show up ;)

-Chris

Captain_Kaboom

I'm definately a noob when it comes to carbs.

I was having problems yesterday accelerating hard. Today when I step on the gas from a stop my RPMs briefly jump, then very briefly fall below my idle RPM, then jump right back up and the car moves out. Are the secondaries supposed to be a little stiff when trying to move by hand, or should you be able to easily push on them to make them open? It was very hard starting the vette this morning ~4 cranks and that has never happend before.

Anyway, while trying to leave from work I popped the hood and revved it while looking at the engine- a good hiss was comming out from the air cleaner when I did; took it off and revved- I had just started the engine a minute or two ago, the choke was wide open and the secondaries didn't seem to budge. I thought the hiss sounded like air trying to be sucked in around them.





[Modified by Captain_Kaboom, 1:11 AM 4/10/2004]