[Ted69lemans]

I'm trying to get the Quadrajet running good on my 69 LeMans 400.
(#16 Heads, factory 69 cast iron intake, CAM is MC1778, 278/288 .420/.443 108 116, 3.55 rear gears, idle set to 800 RPM's in drive, initial timing 12 degrees with vac advance connected to manifold vacuum)

Quadrajet is a 7028250
Carb is running 72 main jets, 42 rods, bb sec rods, k sec hangar. Not sure
how close that is to where I should be.

My part/full throttle response seems great. Even off idle is pretty darn good.

My issues are a rougher than expected idle with just a mild cam - and the car smells rich. I have to take a shower every time I drive it before the wife will hang out with me again cause I smell like gas. :-)

When the car is idling, if I look in the throttle bores I see fuel dripping
from venturi onto throttle plate - which probably isn't supposed to happen.

I orders Cliffs book - so I just tore the carb apart to start investigating the idle circuit.

Here are my question.

First, it looks like the "Main Well Bleed Tubes" are missing.
There are also a couple of blocked off passages.
Check out the picture.

What do you guys think?
Should this carb have main well bleed tubes, and what are those blocked passages? They dont seem to be the main air bleeds.

[Kenth]

You´ve got a "Factory" remanufactured Q-jet.

And yes, the secondary emulsion tubes is missing and from what i can see the upper idle air bleeds are relocated to the fuel bowl.

There is just NO way to advice until calibration is checked.

[67cruiser]

Plus you have a oldsmobile carb. also. Just to let you know.

[Ted69lemans]

I checked the calibration.

Idle tube - .0375
Idle down channel - .0535
Upper air bleed (in air horn) - .070
Lower air bleed - .061
Idle bypass air - .070
Idle screw mixture holes - .094

Not sure what to do now with this carb.
What do you guys think?

[72LuxuryLeMansLa.]

Originally Posted by Ted69lemans

I checked the calibration.

Idle tube - .0375
Idle down channel - .0535
Upper air bleed (in air horn) - .070
Lower air bleed - .061
Idle bypass air - .070
Idle screw mixture holes - .094

Not sure what to do now with this carb.
What do you guys think?

Ted,

In your initial post you stated "initial timing 12 degrees with vac advance connected to manifold vacuum" . You should set your initial timing with the vacuum advance disconnected and the vacuum source plugged.

[Ted69lemans]

Sorry I should have been more clear.

Initial timing was set to 12 degrees with vac advance disconnected.
THEN vacuum advance was connected to manifold vacuum.

[Bobalong]

Originally Posted by 67cruiser

Plus you have a oldsmobile carb. also. Just to let you know.

How can you tell that ?

[thadeal4real]

Originally Posted by 72LuxuryLeMansLa.

Ted,

In your initial post you stated "initial timing 12 degrees with vac advance connected to manifold vacuum" . You should set your initial timing with the vacuum advance disconnected and the vacuum source plugged.

Ported doesn't need to be plugged just disconnected from the distributer

[Blued and Painted]

unless its pulling vacuum from a high throttle angle

[rexs73gto]

If it were my car I'd get a different carb that has not been rebuilt by the aftermarket. They do some thing in there rebuilds that I would never think about. I would get another carb that is all together & has all the pieces & parts in it to start with & when you get Cliffs book go through it as his book says. it will turn out much better when you have a carb thats all there to start with. If the carb is dripping raw fuel into the center of then it's drawing it in because there is a vac. source pulling it down & in. I would think that the missing parts & the plugged ports in the top are part if not the cause of your concern. Put aside the carb you have now & start fresh.

[Ted69lemans]

Originally Posted by rexs73gto

If it were my car I'd get a different carb that has not been rebuilt by the aftermarket. They do some thing in there rebuilds that I would never think about. I would get another carb that is all together & has all the pieces & parts in it to start with & when you get Cliffs book go through it as his book says. it will turn out much better when you have a carb thats all there to start with. If the carb is dripping raw fuel into the center of then it's drawing it in because there is a vac. source pulling it down & in. I would think that the missing parts & the plugged ports in the top are part if not the cause of your concern. Put aside the carb you have now & start fresh.

Good advice.

I bought this on EBay: http://bit.ly/1hwWlVf

The guy I got it from on EBay said the fuel inlet threads looked good but throttle shaft was loose on mains he offered to put bushings in for 35$ so I took him up on it.

I already ordered a new kit float and idle tubes from quadrajetparts.com so plan is to clean and rebuild when I get it and hope for the best.

[Pontirag]

quadra jet =question?

Holley =answer!

[1969GTO]

Pontirag................boo...bad answer ;o)

[Cliff R]

Used to hear that nonsense back in my high school days when gas was 30 cents a gallon and everyone wanted a Holley sticker in the window and to burn everyones eyes who got behind their car in the parking lot after a ball game.

Folks are a LOT smarter these days when it comes to this topic.....well, at least most of them are.

For the OP, we don't even work on commercially "remanufactured" carbs here in the shop, and don't want any sent here. Sure, in most cases we can fix them, but the quality these days with them is pathetic, and they will ALWAYS be butchered up and a MESS for calibration. By the time we straighten them out and get them up to par, I could have built 3-4 original units to do the same thing.....FWIW.....Cliff

[LATECH]

Originally Posted by Bobalong

How can you tell that ?

2nd number from the last is a 5, that designates olds.

[RamAirIV28]

Originally Posted by Cliff R

Used to hear that nonsense back in my high school days when gas was 30 cents a gallon and everyone wanted a Holley sticker in the window and to burn everyones eyes who got behind their car in the parking lot after a ball game.

Folks are a LOT smarter these days when it comes to this topic.....well, at least most of them are.

For the OP, we don't even work on commercially "remanufactured" carbs here in the shop, and don't want any sent here. Sure, in most cases we can fix them, but the quality these days with them is pathetic, and they will ALWAYS be butchered up and a MESS for calibration. By the time we straighten them out and get them up to par, I could have built 3-4 original units to do the same thing.....FWIW.....Cliff

What Nonsense is that cliff?

too bad you did not listen back in those high school days.

Holleys then and now are as good or better than any Qbomb.

Yes Folks are a lot smarter these days when it comes to this topic. Because there are so many well written books on tuning holleys. cant say the same for the q junk.

Holley's are number 1 in sales.

[Sun Tuned]

Well hell I guess they would be, the last q-jets left the factory in what ... 1986?

That's about 28 years Holley has had to catch up I guess without Rochester in the way.

Not too shabby at all.

[RamAirIV28]

Originally Posted by Sun Tuned

Well hell I guess they would be, the last q-jets left the factory in what ... 1986?

That's about 28 years Holley has had to catch up I guess without Rochester in the way.

Not too shabby at all.

So... we're not counting all the ford products that ran holleys....

The thing to keep in mind is that it was holleys and AFB's that fueled the winners. Then and now.

where would Pontiacs image be without a few AFB's crossing the finish line from 57 through 67. Same same for Chrysler boys too.

[1969GTO]

sounds like a pissin match ;o)

[Cliff R]

The only thing wrong with making one stupid comment about carburetors is to follow it up with another.

Last time I looked it was 2014, I really thought we were past all that Holley, high rise intake, Mallory dual point, double hump heads, double roller timing chain, high volume oil pump mentality.........Cliff