I haven't met anyone yet that's put one on and been able to just adjust the
mixtures at drive off into the sunset. Ready to run right out of the box?
The first thing that I would do is connect the distributor vacuum line up to
ported vac "no vacuum until the throttle is opened". Then I would turn the
mixture screws in all the way until seated and back them out 2 turns each as
a starting point. If you have a manifold vac. gauge, I'd connect it up to
manifold vacuum so you can see what the motor is doing and use that to
increase the timing to it's highest vacuum reading and then drop it down 2
points before tightening down the clamp on the distributor. I'd also adjust
each mixture screws to their highest vacuum reading. You should be
somewhere around at least 17 or 18 inches of vacuum with moving the
distributor "unless you have a high lift cam". If it will idle for you, I'd
suspect a vacuum leak at the base of the carburetor where it bolts to the
manifold which can be checked by spraying some WD-40 around the carburetor
while the engine is running. If the idle increases and smoothes out you've
found your problem.
I really wanted one of those carburetors when they first came out but
didn't want to spend the money. Then a friend of my brothers got tired of
messing with his so he dropped of his truck and say that he wanted me to
yank that and build him a 600 cfm Holley with an electric choke because he
was tired of messing with it. No problem! He didn't even want me to see
what was wrong with it ? He gave me the Carburetor after his test drive
with the Holley installed. I found that the following problems:
1. Wrong base gasket resulting in a vacuum leak.
2. Broken choke electric spring "poor warm-up and driveablilty when cold".
3. Very badly adjusted mixture screws
I agree with New Mexico Jim, The Q-jet is the best overall carburetor out
there. Mechanics around here really hate them, I should say "Scared of
them"!!! I'll rebuild them all day long as that's the first carburetor I
learned to rebuild a long time ago.
Joe Garcia
1950 Chevrolet 3100
http://chevy1.freeservers.com/
http://50chevy.freeservers.com/
http://1950Jeepster.freeservers.com/
-----Original Message-----
From: Ben Bennett <greyhawk200@att.net>
To: oletrucks oletrucks <oletrucks@autox.team.net>
Date: Sunday, October 15, 2000 11:49 AM
Subject: [oletrucks] Carb? timing?
>I just had my distributor (ATI) rebuilt and the timing advance
>curve... redid. While I was at it I changed the carb from a
>quadrjet to an edbroke. Now it runs really crappy unless I
>disconnect the vacuum advance. The folks that did the dist. gave
>me a sheet that shows all the timing curves and the initial
>setting. I'm sure I've got it in the right vacuum port. what
>gives? Could it be the carb?
>--
>Ben Bennett
>We have enough youth, how about a fountain of Smart?
>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
>
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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