newly rebuilt quardajet problem
08-26-2009, 03:38 PM
#1
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DYNO TECH
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Join Date: Aug 2007
Location: Colebrook Connecticut
Posts: 425
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!
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!
08-26-2009, 08:26 PM
#2
Senior Member
RACING JUNKIE
Join Date: May 2006
Posts: 2,044
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
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
08-27-2009, 01:59 AM
#3
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Join Date: Aug 2007
Location: Lost Creek, WV
Posts: 533
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
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, 04:26 AM
#4
Senior Member
DYNO TECH
Thread Starter
Join Date: Aug 2007
Location: Colebrook Connecticut
Posts: 425
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.
geez i hate intemittent problems.
08-27-2009, 07:57 AM
#5
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Location: Belleville, IL
Posts: 658
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'.
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'.
08-27-2009, 09:50 AM
#8
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Join Date: Sep 2007
Location: Belleville, IL
Posts: 658
No way... A vette motor in a vette? 
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.
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.
