70 C10 resto-mod (was Chevy culture shock)

right, q-jet is a spreadbore fer sher. I'm unsure which design Edelbrock calls "Performer" though
 
On their website all the carbs are Carter based designs which are square. It appears the “Preformer “ series is just version of. The QuadraJet carb they used to sell is not listed anymore.
Pierre
 
Points adjustment merit badge made me laugh:
 

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TIL that the Holley "umbrella" check valves(or cheap imitations thereof) also fit my old Mityvac vacuum pump. Had a helluva time finding one for this model, though they have entire rebuild kits for other/newer Mityvacs. Turns out the one part I needed is available at any auto parts store :rolleyes:
 
TIL that you can just flip the whole carb upside down to vac test the seat while it's all buttoned up.
This showed that it wasn't seating, so I pulled the air horn off...and discovered my accelerator pump seal was in pieces. Guessing that there's so much carrier in the 2-in-1 "silicone oil" that it broke down the thin parts of the seal. Stuff smells like lighter fluid, but I expected the blue seal to stand up to both petroleum and alcohol and I didn't want to put the pump in dry. ;-\
Fortunately, I had another seal and also got the needle valve to seat after swapping the washer and tapping a check ball to form the seat.
Hard to know what you don't know, but now the accel pump doesn't make that hissing noise
"We know it's right cuz we did it twice" ;-)

Cliff Ruggles' book is full of good info for Quadrajet stuff, but I find Mike's to be much easier to interpret:

Rochester Quadrajet Archives - Mikes Carburetor Parts

Rochester Quadrajet, 4 barrel carburetor technical information. Includes all Quadrajet models. Use this to further understand how your carb works.
www.carburetor-blog.com
 
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Quadrajets work well, and give good mileage, in addition to performance, but there's a lot to know in setting them up right. Mike
 
Older rubber detest alcohol in the gasoline. Hopefully the new ones are better. Came across another item, the cheap fuel filter elements will swell and degrade in oxygenated fuels as well.
Pierre
 
pdentrem said:
Older rubber detest alcohol in the gasoline. Hopefully the new ones are better. Came across another item, the cheap fuel filter elements will swell and degrade in oxygenated fuels as well.
Pierre
Click to expand...
Weirdly, the old black seal on the pump was worn, but had retained it's shape. The new blue rubber seal, which is tolerant of alcohol, crapped out instantly, so I suspected that kerosene-like carrier in the silicone oil I chose had destroyed it. (Stuff smells like lighter fluid)
Now I read this nugget: "Do not allow carburetor cleaner come in contact with pump assembly." I spray that crap like a firehose, so I'm sure I violated that rule.
Guess I found the smoking gun.
 
Waiting on primary bushings+reamer, so working on decrepit paint. Car was 503 Medium Olive when it rolled out of Fremont, now it's something that could graciously be described as silver. You can see hood vs fender what the oxidation looks like
IMG_3546.JPG
Previous owner lived by a golf course, this is an impressive golf ball dent. Dimples and all:
IMG_3552.JPG
 
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