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440 sixpack carbs
#974794
04/17/11 07:00 AM
04/17/11 07:00 AM
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Joined: Sep 2009
Posts: 263
Switzerland, Europe
Swiss_Robert
OP
enthusiast
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OP
enthusiast
Joined: Sep 2009
Posts: 263
Switzerland, Europe
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Hi! Last week I was able to fire up my 1970 Challenger 440/sixpack MT clone again after some years of (lazy) work - while the engine was NOT part of that work (but got a new exhaust system from Accurate - if you're interested: http://youtu.be/wU3zEr-ulvI ). Now I'm dealing with the carbs. They look very worn and my first problem is that I don't get a stable idle. Engine goes up and down at idle and often dies. When I drove the car earlier, cruising or accellerating was not a problem - just idle. I found https://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=4572020&Main=4569194 but this just helped half way... I took the center carb apart and it looks worn inside, too. The shaft in the baseplate has play of about 0,15mm (0,006 inches)which feels like a lot. The choke shaft also has a lot of play and it's outside lever is loose. It has a lot of signs from earlier "human interventions" (like screwdriver marks at jets). It's dirty, throttle flaps got rust ... and so on. Is such a worn carb worth to rebuild (or "renew" using the appropriate kit)? A new would be about $515 (and they are NEW, from Holley - not "professionally rebuild"). I'm considering just to replace the center carb and leave the outboarders or spend them a rebuild kit. Good idea?
After all these years having a 440 I realized that this means having an attitude... and a budget.
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Re: 440 sixpack carbs
[Re: Swiss_Robert]
#974797
04/17/11 11:23 AM
04/17/11 11:23 AM
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Joined: Jan 2003
Posts: 9,436
Blair County,PA
62maxwgn
master
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master
Joined: Jan 2003
Posts: 9,436
Blair County,PA
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Your choke issues are normal,the main body,metering block and bowl (unless needle/seat threads are stripped) don't go bad.Some play in the throttle shaft is normal and can be bushed if needed.The biggest problem I have found is bases not square by being over tightened,also an easy fix.From what you describe,I would check for vacuum leaks before I would consider replacing the center carb.If you are using the thin black base gasket and your base is not square,it "will not" seal.I did thirteen 6pk sets last year and six since mid December,very few had based that didn't need milled.
Good luck.
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Re: 440 sixpack carbs
[Re: screamindriver]
#974798
04/17/11 11:55 AM
04/17/11 11:55 AM
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Joined: Jan 2003
Posts: 9,436
Blair County,PA
62maxwgn
master
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master
Joined: Jan 2003
Posts: 9,436
Blair County,PA
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Quote:
The 6-bbl carbs are tricky to get right...That carb throttle shaft should have teflon seals on each side of the throttle bores...If they're shot or missing completely you'll have a massive vacuum leak from the beginning....But if the shaft and/or bore is wore too hard you're better off with new or sending them out... You can't go wrong using Harms...Scott does excellent work....I guess the ride back and forth from over there would be a factor going the rebuilt route 
I may be missing something but I have yet to see a production line set of unmolested 6pk carbs with the Teflon seals ever though the shafts are cut to accept them.I've seen them on a lot of 4bbl's,not all and a few over the counter replacements but never an original.
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Re: 440 sixpack carbs
[Re: Swiss_Robert]
#974801
04/17/11 05:39 PM
04/17/11 05:39 PM
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Joined: Sep 2009
Posts: 263
Switzerland, Europe
Swiss_Robert
OP
enthusiast
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OP
enthusiast
Joined: Sep 2009
Posts: 263
Switzerland, Europe
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Do you recommed to use another, a "thicker" gasket - or only grind it flat?
I tried to make a pic that shows backlight coming thru under my ruler... but it's not to good...
Outboarders will probably leak too, right?
After all these years having a 440 I realized that this means having an attitude... and a budget.
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Re: 440 sixpack carbs
[Re: 62maxwgn]
#974803
04/17/11 09:09 PM
04/17/11 09:09 PM
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Joined: Feb 2004
Posts: 7,196
Harrisburg, Pa.
screamindriver
master
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master
Joined: Feb 2004
Posts: 7,196
Harrisburg, Pa.
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Quote:
Quote:
The 6-bbl carbs are tricky to get right...That carb throttle shaft should have teflon seals on each side of the throttle bores...If they're shot or missing completely you'll have a massive vacuum leak from the beginning....But if the shaft and/or bore is wore too hard you're better off with new or sending them out... You can't go wrong using Harms...Scott does excellent work....I guess the ride back and forth from over there would be a factor going the rebuilt route
I may be missing something but I have yet to see a production line set of unmolested 6pk carbs with the Teflon seals ever though the shafts are cut to accept them.I've seen them on a lot of 4bbl's,not all and a few over the counter replacements but never an original.
Guess you did'nt see them all then... 
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Re: 440 sixpack carbs
[Re: screamindriver]
#974804
04/17/11 10:31 PM
04/17/11 10:31 PM
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Joined: Jan 2003
Posts: 9,436
Blair County,PA
62maxwgn
master
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master
Joined: Jan 2003
Posts: 9,436
Blair County,PA
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Quote:
Quote:
Quote:
The 6-bbl carbs are tricky to get right...That carb throttle shaft should have teflon seals on each side of the throttle bores...If they're shot or missing completely you'll have a massive vacuum leak from the beginning....But if the shaft and/or bore is wore too hard you're better off with new or sending them out... You can't go wrong using Harms...Scott does excellent work....I guess the ride back and forth from over there would be a factor going the rebuilt route
I may be missing something but I have yet to see a production line set of unmolested 6pk carbs with the Teflon seals ever though the shafts are cut to accept them.I've seen them on a lot of 4bbl's,not all and a few over the counter replacements but never an original.
Guess you did'nt see them all then...
Show me !
Here is another original A12 set,never been apart,I can take another set apart if you wish.You're not that far away,you can even come and watch or I'll meet you half way and we'll do it together! 
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Re: 440 sixpack carbs
[Re: BSB67]
#974810
04/18/11 07:39 AM
04/18/11 07:39 AM
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Joined: Sep 2009
Posts: 263
Switzerland, Europe
Swiss_Robert
OP
enthusiast
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OP
enthusiast
Joined: Sep 2009
Posts: 263
Switzerland, Europe
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That's at least ! I guess it takes warm-proof sealant? And should be used very thrifty? Did you cut a thicker gasket yourself?
After all these years having a 440 I realized that this means having an attitude... and a budget.
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Re: 440 sixpack carbs
[Re: Swiss_Robert]
#974812
04/18/11 10:21 AM
04/18/11 10:21 AM
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Joined: Jan 2003
Posts: 9,436
Blair County,PA
62maxwgn
master
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master
Joined: Jan 2003
Posts: 9,436
Blair County,PA
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All I've ever used is the original Chrysler fiber/cardboard gasket,1/32" thick,never had a problem.Still available through a dealer,pt.# P4529060,includes three each base and air cleaner gaskets.Also,being that your manifold has been modified,I would remove the center portion of whatever gasket you use to match the intake.
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