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Six Pack Idle Mixture Screws Don't Do Much???

Get rid of the yellow springs and install black as mentioned. The outboard carbs do not open in a linear fashion. It's a major dump very quickly then a very slow opening to full. And with the black springs they may never fully open.

The slot size in the distributor plate governs the amount of travel the advance mechanism moves. I just went through this naturally before I was made aware of this table. The more initial your engine requires you must take out from the mech advance to keep the total at 36-38 deg. Just shorten the slot and I did this with a piece of welding rod tacked to either side of the slot bridging the gap.

Most of the long list above is basic tuning instructions just spelled out very well. Engine temp is important for proper fuel atomization and that's why it's stressed throughout the article. Some very good points here.

You can put a spring to hold the outboards closed. And never, ever run without the safety linkage.
 
Are you sure you used the correct Holley gaskets for the carb rebuild? I see in one of your other posts a member posted a picture of a correct gasket to use as I know incorrect gaskets will wreak havoc on the Six Pack working correctly. When I rebuilt my Six Pack I think I found the correct Holley part numbers over on the A12Mopar forum. When I get home tonight I will post up the Holley part numbers from the gaskets I have.
 
Here are the gaskets,correct and wrong.Bottom is correct center metering block gasket,middle is 4 barrel,has small extension on top,looks like bottom gasket but different hole location,top is 4 barrel with transfer tube.Get either one in by mistake,it will run never as it should.
 

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The slot size in the distributor plate governs the amount of travel the advance mechanism moves. I just went through this naturally before I was made aware of this table. The more initial your engine requires you must take out from the mech advance to keep the total at 36-38 deg. Just shorten the slot and I did this with a piece of welding rod tacked to either side of the slot bridging the gap...........

And if you a hesitant on welding this may be your ticket.....................

http://www.4secondsflat.com/Mopar Mechanical timing limiter plate.htm

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Running just the center carb will not get you anywhere,the end carb idle circuits have to be in the mix to get it right.

Agreed. The thought process in my mind was to first rule out the center carb for an overly rich feed and possible leaking condition of the outboards.
 
Thanks everyone!

Daves69- that is EXACTLY what I'm looking for on the distributor.
62Max - Thank you very much! You don't happen to have a picture like that for the outboards too do you?

My plan right now is to check the plugs & probably rebuild the carbs again to check the gaskets..... geez I hate doing that, but oh, well.

Does anyone know what I should use to poke through all the holes in the carb & exactly which holes I should be extra careful to get clear?
 
Here's the Holley part numbers for the correct Six Pack gaskets. these are the blue reusable gaskets

108-83-2
108-90-2
108-200
 
Just a quick post to say thank you to all who participated in this thread.. I have the same issue with my six pack; running very rich.. Tons of great information in here.

440Beep,
Was it a gasket issue; did you ultimately get this resolved?
Thanks!
 
I wasn't having an issue with my Six Pack. I read from others that incorrect gaskets wreak havoc as incorrect passages are blocked, etc. My Six Pack runs pretty well but I may need to revisit some things come summer.

I just discoverd this past fall why my Six Pack was running rich and I had no tuning ability with the center carb idle mixture screws. The outboard carbs mixture screws were turned out 3 turns. Reset them to 1/2 turn out and now my center idle mixture screws actually work at controlling idle vacuum.

And to the OP, every time you adjust your idle speed or timing, you need to retune the idle mixture screws for highest vacuum. It's not a set it and forget it type thing. Idle speed and timing are going to affect the idle mixture screw adjustment.

Just a quick post to say thank you to all who participated in this thread.. I have the same issue with my six pack; running very rich.. Tons of great information in here.

440Beep,
Was it a gasket issue; did you ultimately get this resolved?
Thanks!
 
Hello Everyone, I'm still struggling with this situation. I have two plans. Plan A is rebuild the carbs for the 3rd time & Plan B is a 750 4bbl.
 
Purplebeeper, where at in Chicago are you? I'm just over the border in NW Indiana. Perhaps a get together might shed some help on the situation.

If you do rebuild, be sure to double triple check the Holley gaskets you get. Chicago Carburetor has Six Pack parts as do the other mentioned shops. If you have the Six Pack hand book, I would try and set everything back to factory specs and go from there.
 
The main questions I have on the six pack are 1) There's definitely "something" gummed up in the center carb metering body idle circuit on the driver's side. I'm seriously tempted to buy a new/used metering body if I can find one since I already drilled the holes in the power valve hole. Where can I find a new metering body? 2) Making SURE I have all the correct gaskets & double checking my outboard metering plates. The last ones I got were from Ebay and were in plastic zip lock bags...maybe correct...maybe not? Overall I would like to get back to stock and work from there, but probably have to use at least a 4.5 power valve due to low idle vacuum. As of now, it still reeks of fuel & blows sooty black smoke at idle. It idles best with all 4 outboard mixture screws turned all the way in & still acts like it wants to be leaner. The driver's center carb idle mixture screw does nothing.....somethin' ain't right.
 
Set your initial timing at 15*,idle speed at 900 rpm,center carb screws out two turns,end carbs 1/4 turn and do what the second paragraph of the attached form tells you,adjust each screw one at a time until there is no change in idle speed then go back and re adjust center carb screws and idle speed.As for metering plates,69 1/2 use plate #6178 front,#6180 rear,70 uses #34 and #35 rear,340 uses #41 both front and rear.Wondering what main jets you are using and be "sure" you have no vacuum leaks and also the correct metering block and metering plate gaskets.
 

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Thanks 440beep, I've boughT stuff from them before...not actually in Chicago, but I didn't see any metering bodies last time I looked.

Thanks 62max. I tried that cover the air bleed holes trick on the outboards & I had no idle change at all up or down with any of the four holes???? I'm running '70 4-spd carbs & I "think" I've got 35 metering plates both front AND back, so I better check that. I'm pretty darn sure I don't have a vacuum leak. My vacuum gage looks steady and it doesn't hunt for idle. I can't remember off the top of my head, but I believe I've got stock jets or maybe 1-step larger in the center carb. I had been 3-4 steps larger with jets, but stepped them down to stock/almost stock the last time I pulled the carbs apart. It just seems like I might have wrong gaskets, plugged metering body, wrong metering plates..... a bunch of little things all adding up to a rich idle. COMMON WARM WEATHER!
 
The main questions I have on the six pack are 1) There's definitely "something" gummed up in the center carb metering body idle circuit on the driver's side. I'm seriously tempted to buy a new/used metering body if I can find one since I already drilled the holes in the power valve hole. Where can I find a new metering body? 2) Making SURE I have all the correct gaskets & double checking my outboard metering plates. The last ones I got were from Ebay and were in plastic zip lock bags...maybe correct...maybe not? Overall I would like to get back to stock and work from there, but probably have to use at least a 4.5 power valve due to low idle vacuum. As of now, it still reeks of fuel & blows sooty black smoke at idle. It idles best with all 4 outboard mixture screws turned all the way in & still acts like it wants to be leaner. The driver's center carb idle mixture screw does nothing.....somethin' ain't right.
if you take the main jets out of the metering block you'll see a small brass tube in the main metering wells. these tubes have a small orifice at the bottom that is the idle feed restriction. i have seen them get a small piece of dirt over the orifice and really play havoc with idle. the dirt will prevent fuel from entering the idle circut rendering the mixture screws useless.
 
You said you plugged the idle air bleeds with your finger and get no change. Is this on all three of the carbs ? Of course it should cause a change since you are blocking some idle circuit air. It should go richer and change the idle speed a little. But thats why I wonder if it does not change on all the carbs. It does make you think a gasket can be wrong blocking the idle air bleeds which would cause it to run rich like it is. Or dirt and gum in the circuits. You know even if your power valve was wrong and was open at idle it wont cause it to run rich if its idling right on just the idle circuits. The diaphram would have to be blown on the P/V as then it would pull raw gas right through the P/V. Ron
 
Hey Purplebeeper, I just thought of something. You said that you (or someone) drilled out the metering block power valve channel restriction? On the center carb? I had a 3310 carb where someone had done the same thing. Boy that thing ran so rich that it would blubber all the time. I put in a power valve eliminator plug, then it ran fine until you got past 1/4 throttle, then it would lay down and go flat. I put in a metering block with a noticeably smaller power valve channel restriction (PVCR) and that solved the prob. So I would try that. Get a stock metering block and put it in along with the correct power valve.

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The PVCR should only affect the mixture once the power valve opens, unless the power valve is leaking, which isn't likely. I would get a stock metering block and try that on the center carb.

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Keep us updated. I am planning on putting a six pak on my 440 Roadrunner. I'm learning alot here about what to do and what not to do.
 
Purple I P.M. You! What an AWSOME thread, my carbs are # center 4144- outboards 4393-4394 consecutively, in reading/chechecking them out I went to
(google) Holley Carbs Date #s my carbs are 1969 1/2 -1970 and call for CK-038
rebuild kits ALL THREE same kit HENCE MODEL 2300, same as it was 40 years ago,haha. In looking though there ARE OTHER KIT #S FOR OTHER CARBS!! check
the #s AGAIN !Good luck and DOUBLE AWSOME THREAD MEN !!!
 
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