This was an interesting problem I've never seen before. It took a minute but we figured it out. I thought I'd see if anyone else had run into this. TL;DNR - Piston in upper right assembly had the pin back out and lock the choke fully closed. A buddy had his car sputter, miss, backfire and die a while back and it wouldn't restart. It was cranking slow and would sort of catch but wouldn't run. He thought the worst and bought a new plugs, coil, starter and ignition module. He works odd hours and can't always run to town to get parts and wanted everything it could possibly be on-hand if we needed it. I finally got over to help diagnose it this last weekend. He'd already changed the fouled plugs but hadn't tried to start it yet. They were soaking wet with gas. First we checked the coil, 1.8ohms so that looked good. Next, we check the rotor, cap and cranked it over to test the module. We had a strong blue spark from the coil. Then, we put it all back together and tried to fire it. It caught on the second try but was loading up quick. I tried to open the choke but it was locked closed. It wasn't opening at all. I slipped a screwdriver in and opened it a little but it was really tight though it did start to idle better. He shut the engine off and left the key on for a few minutes to see if the electric choke would pull it off. The choke coil did heat up but it never did pull the blade open. I loosened the choke assembly and it would roll back and but not release the choke. With the cover off, it is still locked in place. We popped the tiny clip off and released the choke blade linkage from the electric choke. Then the blade would open freely. Now, we had it isolated to the electric choke housing assembly. Upon close inspection, the piston was jammed at the top of its travel, full choke. The pivot pin in the piston had moved out and locked it there. We used a punch to restake it, reassembled and it all seemed to be working again. I'm not an Edelbrock carb expert but that was an interesting problem. We suspect that possibly the backfire blew the choke pull-off piston out of the bore and dislodged the pin.
never had that problem. but on 4 different carbs, the bottom hole on the outer side in the photo if not plugged would have a vacuum leak.
I could’ve had this problem. I have the AVS on my 65 Fairlane, it starts , idle and runs really good. So I purchased one for my skylark, drove about 15 miles no issues, a couple days later me and the Wife goes for a ride fill up with fuel hit the interstate, car acted like it was missing, stopped and car would start back up. I had it towed back home about 4 miles, started digging into what was wrong. The choke blade had closed completely and wouldn’t allow air in the carb to start. I stuck a folded piece of cardboard in it and it started up. I boxed the carb up and took it back to the parts store.
First Guess: Not "plugged", it should be GASKETED so it seals to the matching carburetor vacuum passage. The gasket is pictured inside the larger choke coil gasket, with the three tabs that go on the three choke coil retaining screws. Because if the idle-mixture and main jetting is correct, the engine will run like shiit without a choke when cold. Most folks apparently run the carb overly-rich, and with excessive "warm-up" time, covering up the lack of choke. If the carb was tuned better, the lack of choke would be more obvious.
Are you saying the ones without a choke mechanism don't have a vacuum leak sealed off? WOW! Exactly! If it runs fine when cold without a choke, it is a pig rich jetting.
The "bottom hole on the outer side in the photo" is of the choke housing. THAT hole does not get plugged, it gets sealed to the carb body with a gasket. Carbs without a choke housing wouldn't need the hole in the choke housing plugged, they'd need the hole in the carb body plugged. Same vacuum passage, but on different castings.
there are 4 carb boxes there plus one that a friend put on his car so 5 carbs that leaked at the hole i show i plugged with that screw in the photo.don't know what else i can do to prove they had a leak there, am willing to take a lie detector test if need be. lol if i recall it just leaked at idle only.
Both Joe AND Shurkey are right, I see it on hot air choke Q-Jets all the time. Those housings were designed to be hot air chambers, with the heat coming from a tube routed through the intake or exhaust manifolds. In an electric application, it does not need the vacuum to draw hot air into the choke hosing and should be blocked. Surprised thats not in the installation instructions..!! And even when they do work on hot air, you need both tubes in the system to not draw in unfiltered air (2nd tube generally allows air from the airhorn to be drawn down to the heat location source.. how that works under intake vacuum I have no idea)
