HELP - 6 pack woes

[am3rican]

Man...it seems never ending with this car. I finally get a chance to install the vacuum pump and she won't start. Carb cleaner and cranked for several minutes with breaks not to burn out starter. She always took long to start but this time was abnormal. Turns out I have no spark coming out of coil (this will get replaced) I also noticed fuel is leaking from the center carb. Looks like it is leaking from the idle mixture screw.

It looks like my idle mixture screw are too far out and this is where it is leaking from. I don't know anything about 6 packs. Need advice on what to do next with the carbs. Pictures dont show it well, but there is fuel pooled under where the idle mixture screw is

Long story short:
- in June I replaced the throttle body gaskets and intake manifold gaskets for all three carbs. The center gaskets were brittle and leaking fuel onto the intake manifold. It was leaking when I bought it. I think the PO may have adjusted for the leak which is why the idle was so high when I got it.
- It's been idling oddly since I replaced the gaskets. It almost feels like it stumbles at idle.
- I haven't been driving since I replaced those gaskets because at the same time, I converted the manual drums to power discs. Vacuum was too low for the brake booster. Just getting around to installing vacuum pump

 

[lewtot184]

there's a small cork gasket/sleeve that seals the mixture screw and probably needs replaced. also take a good look at the accelerator pump and check the main body for warpage. busted ballast resistor may be your starting problem.

 

[am3rican]

Thanks. I'm thinking of just buying the reseal kit. Know where I can get this? I've had bad luck in the past from my local shop ordering wrong gaskets.

No spark from coil to distributor. How do I check Ballast resistor?

How can I check for warpage? Just visual? What should I look for.

 

[Seventy]

Call Promaxcarbs, he sells rebuild kits and parts cheaper than anyone i have dealt with, and in his rebuild kit you can pick that parts you want, like power valve, etc...

 

[lewtot184]

Thanks. I'm thinking of just buying the reseal kit. Know where I can get this? I've had bad luck in the past from my local shop ordering wrong gaskets.

No spark from coil to distributor. How do I check Ballast resistor?

How can I check for warpage? Just visual? What should I look for.

you can test a ballast resistor with an ohm meter. just about as easy to just change it. use a straight edge to check the carb body where the metering block mates up. i've had them get "warped", probably from over tightening.

 

[am3rican]

You guys are great. Thanks so much for the advice.

 

[440beep]

Here's Chicago Carburetor's Six Pack parts.

http://www.chicagocarburetor.com/carburetor-parts.php?c=2354

 

[am3rican]

I'm replacing the ballast resistor and coil. Can I run an msd coil and resistor if I have a non-msd style electronic ignition system (it's oem style).

 

[uwss]

you need to send the carbs to Promax; they will check everything and mean everything; then they will dyno the carbs to make sure they are performing. You can always upgrade their throttle bodies, etc. if you want. I sent mine off and was shocked as to the number of wrong parts.

 

[Seventy]

you need to send the carbs to Promax; they will check everything and mean everything; then they will dyno the carbs to make sure they are performing. You can always upgrade their throttle bodies, etc. if you want. I sent mine off and was shocked as to the number of wrong parts.

Can't agree enough, its winter time, pock the cah and send them out...

 

[RJRENTON]

Carb woes

It is difficult to see from your pix but the idle adjust screws seal to the metering body with an o-ring type seal. These seals are usually part of the carb rebuild package. Remove the screw entirely, pull out the old seal, press in a new seal with your finger or a small socket wrench, just to get the seal to bottom out in the body and then screw in the mixture screw. In '69-71 applications (original OEM carbs) these screws adjust the fuel flowing into the metering body and ultimately into the throttle bore BELOW the throttle valves. The small milled slots, immediately above these idle feed holes are the idle transfer circuit, which help with the fuel flow during the transition from idle to main nozzle flow. Most 6 barrel cars (Plymouth) or six pack cars (Dodge) use this type of metering system. Also missing from your pix is the primary fuel bowl vent system.....usually a flapper valve on pre 1971 cars, except California using the CAP system of vapor recovery, then the '71 50 states cars used a vapor recovery system with a nipple on the fuel bowl and a hose leading to the passenger side valve cover air inlet fitting. The fuel vapors were stored in the crankcase and purged by the PCV on engine restart....everyone else used a charcoal canister. The original fuel bowl retaining screws were slotted....later Holley issued carbs used hex headed bolts.
If low vacuum issues are noted...lack of assist with a power booster, make sure you are using a BENDIX TANDEM DIAPHRAGM booster, designed to operate on lower vacuum....usually supplied on OEM Hemi engine cars and 6 pack cars with power disc brakes....A-34 super track pack option cars. My car is an original RS23V0A****** 4 speed car with the A34 option and I have the Bendix Tandem Diaphragm booster unit and I run a Crane cam equal to the Mopar 292 / .509 lift cam (lumpy idle) without any difficulty....but I idle at approx. 1500RPM hot. Questions...???? PM me if you want.
Cheers,
RJ Renton

 

[biomedtechguy]

I recently rebuilt my center carb. The idle mixture screws were at about 3 1/2 turns out. I replaced a bunch of gaskets, and the cork idle mixture screw gaskets, and replaced the too small #62 jets with 1 number bigger than stock #65s. Runs great and I am about 2 turns or less out now. My new accelerator pump diaphragm leaked, so I put the old one back in. I wouldn't recommend the Walker rebuild kit, that's what I got, and it had the leaky accelerator pump and didn't have a silicone fuel bowl check valve.

 

[am3rican]

Taking the carbs off now to send to Promax. They said they rebuild 3 or 4 six packs a month. $450 for a rebuild and dyno.

Now just need to buy the new ballast resistor and ignition coil.

 

[Seventy]

Taking the carbs off now to send to Promax. They said they rebuild 3 or 4 six packs a month. $450 for a rebuild and dyno.

Now just need to buy the new ballast resistor and ignition coil.

Good call!!! I would consider the jet plates and rear outboard baseplate, its adds a few hundred but is worth it, also his braided lines are a nice touch, not just for flow and ease of installation, but they dont leak, lol... I have 3 sets to send him but I am waiting until after the holidays, I almost sent them out last week but I was too busy and now decided to deal with them next year...

good luck

 

[am3rican]

Update: sent the carbs out last week. Opted for the jet plates, rear outboard baseplate and new braided lines. Was a little late getting carbs out the door as Xmas put a hurting on finances and available time. Grand total for rebuild, extras and shipping was almost $1000.

Got her running before I sent the carbs. Ignition coil and ballast were Both bad. Ethanol really gunked up the carbs. I will be double dosing on stabil going forward.

 

[uwss]

problems I found after much trial and errors:
1. carb gaskets can cause the throttle body to warp when tightened causing the throttle blades to stick: get the green ones from Promax, those won't compress so much as to bind the shaft;
2. throttle cable can be too stretched not allowing the blades to open all the way, WOT: I installed the Lokar universal one and took about 1.5 hours start to finish, works damn good;
3. If your running a hot cam and your vacuum is around 5 ", delete your power valve and up your jetting;
4. You must adjust the center carb using a vacuum gauge period, adjust one side then other to get the highest vacuum reading;
5. The rear carb will cause your rpm idle to go and down;
6. I set the front and rear to 2 turns out after trial and error;
7. put your fingers over the 2 outside bleed holes on the front and rear carb: if it slows down it needs more air and fuel, so turn it CCW until you find a happy medium between RPMs going up and down, you might want to turn it 1/8 or less to lean it out slightly;
8. Put new plugs ins and drive a short distance stop pull a couple plugs and looks at: if its a nice tan color your are good;
9. Your accelerator nozzle "aka" squirter is next: if your car hesitates on acceleration you will need to go up on size on the squirter;
10. I installed the purple springs on the diaphragm so far no complaints.

 

[biomedtechguy]

Reviving this thread. I paid for all of the Promax parts for the 6 bbl systems, EXCEPT for the fuel bowls, which I will talk to them about.
If their clear bowl screw windows don't deteriorate, that is a plus for maintaining proper level without rags for spillage of fuel and extra steps.
My 6 bbl setup has worked pretty well, but I have occasional idle stability issues (it will idle fine at 850-900 RPM and then on the same day it can go to 1050-1100, or sometimes too low to keep running.
Also seems to want to always creep to too rich over time, burning my eyes and all of the other problems associated with that.
When the 6 bbl is done right, I've never experienced anything as cool as that, and my outboard carbs have always seemed to come in just right, after I adjusted the rods that link to the center carb "slide" so they wouldn't bind.
I plan on having them install all of their parts, and do a Holley rebuild kit rebuild since I used a non-Holley kit, which I've read numerous people have had problems because of using non-Holley kits.
Basically I am going to give them free reign to do everything they can do I have less to do once I get the carbs back, and an easier, more efficient way of tuning them from now on. That will really come in handy when I top my future stroker motor with the 6 bbl setup.

 

[biomedtechguy]

I will have to see about making adjustments for vacuum advance with my FBO ignition system I got from Don.
If I recall correctly, it uses MANIFOLD vacuum, not vacuum from the center carb metering block, so I should be ok. I'm pretty sure that I have the choke diaphragm hooked up to the metering block vacuum, so I will have to do something about that.

 

[6PKRTSE]

I have rebuilt mine & several other peoples carbs for them using the Holley 37-1543 part # I think it is? Comes with most everything needed & only like $14.99 per kit my cost (X3 for each carb).

 

[biomedtechguy]

OEM Holley rebuild kit is THE ONLY CHOICE that should be made PERIOD!
I have read that so MANY times from so MANY highly regarded and experienced people.
I am going to get Promax to rebuild all 3 of my 6 bbl carbs when they install the multitude of Promax parts I bought, unless that is incompatible with the Promax center carb metering block or any of the other Promax parts.