Hi guys! Hi Doug! it's Jon Bastian! Hey, it's Been a minute! Hope everyone is well here in this magical place!

Stats: 65 Valiant 225, 1 barrel Holley(recently rebuilt by a reputable friend MoBill in San Francisco), Electronic Ignition but with generic black ecu box, but not orange box.

Symptom: Car starts up fine with choke and is good for moving around the neighborhood while it's still somewhat choked and not fully warmed up. After it warms up and i start driving it on an errand it starts dying on final de-acceleration near and at stop signs. It will start back up easily after i pump the gas once and will stay running as long as i keep it revved. I've got the Idle screw all the way in as far as it will go so i don't believe it's that. My vacuum hose from the Distro to the Carb seems ok. I'm ready to start eliminating more variables, PCV valve etc. but anything else y'all wanna throw at me i'd be glad to listen to and try out! Need these wheels running TODAY so i can go to work tomorrow!

Many thanks in advance!

Carburetor operation and repair manuals and links to training movies and carb repair/modification threads, carb adjustment procedures, etc are posted at http://www.slantsix.org/forum/viewtopic.php?t=33102 for free download. Neither the idle mixture screw nor the idle speed screw should be "all the way in".

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I've had a similar problem on Holleys and the problem turned out to be fine particles in the valve body that I couldn't remove. I suppose you would have to remove the plugs in the valve body to get it clean. I would remove the idle screw and blast in the idle screw hole with compressed air to temporarily clean it out. It would then run for another 5 miles or so.

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Chuck Rivers, Webmaster

Thanks Chuck and Dan for the replies! Chuck I think you're onto something. I took the carb off and blasted all the little passages i could get to without taking the floatbowl off including the idle mixture screw and it worked great! Got my idle back! Took it on the freeway. Floored it and activated the passing gear! Totally normal amount of power. Things were going great til i got almost home and bang! Same exact problem. UGH. As i de-accelerate and start coming to a stop it very quietly just dies. Then with a little squirt from the pedal fires right back up with no hesitation. Then it's the battle to keep it running enough to limp it home.

Dan when i said i had the idle screw "all the way in" i meant the idle speed screw but in the warmed up position, choke off. I did this to keep the car running while i fiddled around. After i cleaned the carb including the idle mixture as Chuck suggested i was able to back it off to normal-ish setting and it was like "almost normal" maybe just a little rough like it needs a proper tuneup however i do know my air bleeds aren't in the greatest shape.

If Chuck's suspicion is correct, do you guys think this is something that will "work itself out" over time or should i seek a carb whisperer?

JB

Make sure your valve lash is well adjusted. These symptoms can come from that since when the engine warms up the valve lash goes away and it has no vacuum and will die at idle.

Lou

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