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-   -   newly rebuilt quardajet problem (https://www.racingjunk.com/forums/showthread.php?t=25461)

rabiddawg 08-26-2009 03:38 PM

newly rebuilt quardajet problem
 
after problems with vacum leaks at the base bushings and a stuck accel pump I had the carb for my 69 vette rebuilt by a reputable carb shop.
every carb he built for me worked flawlessly.
except this one.
ok mixture screws set at 4 turns out
19" of vacum
no external vacum leaks.
primaries work great but once I get into secondaries it sputters and breaks up a bit.
doesnt seem to open secondaries at all?
but in park and operating without a load they open?
any ideas?
Im a holley man and this quadrasuck is a pita!

cepx111 08-26-2009 08:26 PM

The air valve (top set of butterflies) on the secondaries could be out of adjustment, very tricky to set right if they've been messed with.
If they open to quick you'll get a bog when you go WOT if they open to slowly you'll get poor performance @ WOT.
The way you desribed your problem sounded like they may be opening to slowly.

Make a small adjustment on the spring (looser) and test drive it and see if it's better or worse and then make appropiate adjustments there on.

Hope this helps, Cp

TS1955 08-27-2009 01:59 AM


Originally Posted by cepx111
The air valve (top set of butterflies) on the secondaries could be out of adjustment, very tricky to set right if they've been messed with.
If they open to quick you'll get a bog when you go WOT if they open to slowly you'll get poor performance @ WOT.
The way you desribed your problem sounded like they may be opening to slowly.

Make a small adjustment on the spring (looser) and test drive it and see if it's better or worse and then make appropiate adjustments there on.

Hope this helps, Cp

X2...I worked on one for a couple of hours one day before I got it right. Q-jets can be a pain sometimes. But when they are right they work pretty good. JMO.

TS1955

rabiddawg 08-27-2009 04:26 AM

well i took the car out this morning and secondaries open as they should (maybe a bit slower than normal) but much better than before the rebuild.
geez i hate intemittent problems.

OneBadGMC 08-27-2009 07:57 AM

cepx111 hit the nail on the head.

And when he says make small adjustments, he means SMALL ADJUSTMENTS.

If you can feel that screwdriver move in the least, tighten up the set screw to lock the spring and go try it.

Quads are great carbs when tuned right.

How wild is the motor, and what secondary metering rods and hangers do you have on it? The hanger should be a single 'letter' while the metering rods will be two 'letters'.

rabiddawg 08-27-2009 09:38 AM

original 69 corvette 350 smallblock
wifes car.
http://webpages.charter.net/harrycoo...69%20vette.JPG

DirkaDirka 08-27-2009 09:45 AM

WOW thats a nice vette!! That is one lucky lady.

OneBadGMC 08-27-2009 09:50 AM

No way... A vette motor in a vette? :D

My dad worked at Carter for over 25 years. Started off running a punch press in the basement in STL. When he left, he was Manager of Manufacturing over all of STL, then transferred to Lafayette, TN to turn the fuel pump plant down there from the shithole it was into Fords Q1 supplier.

He brought home a LOT of neat toys to play with over the years. I still have a couple carbs that were prototypes, along with a WCFB for a mid 50s vette that was never bolted on a motor.


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