Everything you wanted to know about automatic chokes but were afraid to ask pt4
I've noticed many people drive vehicles with inoperative chokes. Even though chokes can be intimidating, repairing and adjusting them actually is very simple.
So, stop pumping that accelerator and follow along as we look at how chokes work and how to repair them.
How to adjust Quadrajet/Dualjet fast idle
Quadrajet/Dualjet Rochesters have a fast idle adjustment screw that is
separate from the base idle screw.
Here's how to locate it.
Note: Ever since Charter "fixed" my internet and cable after the lightning
strike, it hasn't worked right. Go figure. So, if you see this posted then
I was finally successful in getting a video uploaded.
Identifying vacuum ports, late-style Quadrajet
I always see a lot of questions about what various vacuum ports do on a
Here's a general guide that will point you in the right direction.
Remember that there were many different Qjets over the years and vacuum
port locations and number will vary. This video is representative of
How to de-bog your Quadrajet part 2
The Rochester Quadrajet has gotten a bad rap over the years, but it's
actually an excellent carburetor once you understand how they work.
Often referred to as "Quadrabog" or "Quadrajunk", many of the issues these
units suffer stem from neglect, or "modifications" that do more harm than
Being a spreadbore, air-valve secondary design, the Quadrajet is capable
of flowing 750 or 800 cfm of airflow, eliminating the need to buy different
carburetors when your set-up changes. In addition, the small primaries make
for great drivability and fuel economy.
In this clip, I'll discuss theory of operation on the secondary side,
since that's where most problems arise. So, leave your preconceived notions
at the door and let's see what makes these carburetors tick.
750 vs. 800cfm Rochester Quadrajets-how to tell them apart
There exists a ton of misinformation regarding the actual airflow capacity
of the Rochester Quadrajet. Not many people know how many variations there
are or how to tell them apart.
Here is a simple video explaining how to identify each size based on
casting design. I will cover the "cfm-limited" carbs in a separate video.
Quadrajet air leak fix and warped air horn repair tutorial.
How to identify a Quadrajet with a warped air horn without diss assembly or
running it on a car. These tips would have saved me time and money which is
why I made this video. I also discus how to repair a warped air horn and
prevent your air horn from warping in the first place. If you have a
whistling noise just off idle then you got some work to do. You will never
get your engine tuned right, your cold start performing or decent fuel
economy unless your four barrel carburetor is just right. Special thanks to
Cliff Ruggles for his book Rochester Quadrajet carburetors and to my
brother Adrian who spent hours on tuning and fitting.
See this video for description of the technique I used to straighten a
warped air horn.
Fixed the choke on my '79 Dodge 100 truck. Cold start & drive
Sometime this winter I decided to figure why my truck had to warm up so
long, I had made a video of the carburetor last winter so I could see what
was going on, and hoped someone on YouTube might be able to tell me if
something was wrong. No one noticed the problem, but a year later I
eventually figured it out and fixed it.