Am I Cursed by the Carburetor Gods? Or do I just suck with Carburetors?

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RecklessWOT

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You said the vacuum advance is still attached but "sometimes it likes it and sometimes it doesn't". Is your timing just all sorts of messed up? I'd unhook that and just set it somewhere conservative.
 

jjester6000

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You said the vacuum advance is still attached but "sometimes it likes it and sometimes it doesn't". Is your timing just all sorts of messed up? I'd unhook that and just set it somewhere conservative.
I tried that, and it ran good again, then didn't, then decided it wanted to flood out, then wanted to lean out, then caught fire, then I hooked it back up, and it ran good again, then it wanted to lean out, then flooded, and caught fire, then it wouldn't even start.
(Are you starting to see a pattern?)

Anyways, I put a whole brand new distributor in it last year and used it in th new motor as well. The dwell and timing are perfect, and when it does run good, it purrs like a kitten.
 

Dmack

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I had a condenser go bad years ago, which caused intermittent problems of rough running and backfiring. Loose mount\connection or an internal issue. Cheap and easy to swap out. Just a thought.
 

jjester6000

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SHE LIVES!!!.
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I stuck the new carb on, and it started right up and ran really good. I don't know for how long though.
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Here's where I welded the linkage pieces from one of the old monojets on.
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SquareRoot

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Well there's your problem, you're missing a whole bank of cylinders! Don't even contemplate a Holley EFI, you think you got problems now.
 

medicmudder

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Morning this may sound crazy but check the fuel pressure I had the same issue no matter what I did it still had the issue the fuel pump was putting out to much fuel put a pressure regulator worked great !!!! Check the fuel pressure!!!
 

Copymutt

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Bad ignition wires can cause cross fire when they get close to each other. Ck. for deterioration and routing away from each other.
This would most likely be intermittent.
 

olnick

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I'm with Dmack ! Installed new points/condenser did a major tune up sat all winter then had issues like yours! I KKNEW IT WAS THE CARB!!! finally got sick with it running like crap all the time. Put the O scope on it and Damn primary wave for was all wrong. The new condenser was bad my coil was kicking back 600 volts intoo the primary. I replaced the condenser with one I had for my Bug that was 3 years ago. Runs like a champ and the POS carb is still on there running smooth i did not touch it after the ccondenser replacement But I knew it was the carb,!!!

OLNICK
 

seniorbear69

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check the carb to manifold gasket .make sure it seals the carb to manifold no open air ways .dont ask how i descoverd this !
 

75Monza

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I had real similar luck with an old 230 in a 65 nova I had, single barrel. Seemed like nothing I did could get it to run right over idle...if I could even get that. Original carb, rebuilt it, would go too rich to where exhaust manifold would glow from exhaust overtemp just trying to get damn thing to run. Replaced whole ignition with no luck, adjusted valves, fuel delivery to carb checked out, couldn't find any vacuum leak. Leakdown test on cylinders was not the greatest. I never did dig into the timing chain, but suspect something was not quite right in there because would end up raw fuel dribbling out exhaust sometimes. Finally end up selling it since it was a free car and 4 door just to get it out of my hair and give me time to mess with my 2 door 64 instead, lol. About all I figured was v-8, 4 barrel and HEI was alot easier to troubleshoot than that damn setup for sure. If engine mechanical is sound, it's basically spark or fuel problem that I would start with spark, verify complete ignition, then work on the fuel. Since an engine is just an air pump, verify no intake restrictions and same with exhaust since I've had a rat's nest inside a muffler before blocking off air flow so severe backpressure.
 

rt66paul

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Is this the six with the incorporated intake manifold? The fix is to use an older head and manifolds, those heads crack and do suck air. They can do it intermittently and drive you crazy. The fact that you have a burned exhaust valve could show a bad vacuum leak, you are running too hot.
I think it is a combination of things, replacing a carb on a vehicle with other problems does not fix the earlier problems.
 
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