Correct Color and Plating on Q-Jet Carbs
10-21-2016, 07:14 PM
#1
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Correct Color and Plating on Q-Jet Carbs
There is a good thread with good photos over in the C3 General Section about correct plating and appearance of Q-Jet carbs. It's good info for those of you looking for correct, original used carbs, and it gives you a good standard to compare against so you can identify the dreaded "commercial rebuilds" from their appearance.
Lars
https://www.corvetteforum.com/forums...rb-colour.html
Lars
https://www.corvetteforum.com/forums...rb-colour.html
10-22-2016, 10:11 AM
#2
Racer
? 4 Lars
There is a good thread with good photos over in the C3 General Section about correct plating and appearance of Q-Jet carbs. It's good info for those of you looking for correct, original used carbs, and it gives you a good standard to compare against so you can identify the dreaded "commercial rebuilds" from their appearance.
Lars
https://www.corvetteforum.com/forums...rb-colour.html
Lars
https://www.corvetteforum.com/forums...rb-colour.html
I just read the above posting and would like to know why anyone would drill out the bleed hole on the pulloff???? As a matter of fact I am not even sure that I could find that hole????....
Any of your expertise regarding will be appreciated
mk's78 Mike...
And btw my 78's starting after a week or longer has greatly improved since I took your advice and replaced the fuel pump....You were spot on!!!!
10-22-2016, 11:34 AM
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People drill the bleed hole to make the pulloff "relax" faster for quicker secondary airvalve opening. The bleed is right inside the vacuum nipple, so all you have to do is run a drill bit in through the nipple. There are some pulloffs that have a very slow "relax rate," so a slight increase in bleed hole diameter can be of benefit. But most people doing the drilling simply drill out the bleed entirely, which results in the airvalves opening prematurely, and inducing a bog when transitioning into the secondaries.
Lars
Lars
10-25-2016, 04:10 AM
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Le Mans Master
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I have a carb that was acid tanked before rebuild and even here in dry Nevada it's getting covered with surface rust on all the steel parts. I should have sealed it in a bag when I had the chance. All original carb though. Acid tanking does a darn good job of cleaning though and relatively fast. Wish there was a good eco-friendly dip to replate them. Painting and powder coating takes to much prep work.
Can't have to many spare carbs. And I picked up another q-jet core this summer for ten bucks plus $2 entry fee to the swap meet. Has APT and electric choke too - but only 750cfm. I can live with it though.
Can't have to many spare carbs. And I picked up another q-jet core this summer for ten bucks plus $2 entry fee to the swap meet.
Has APT and electric choke too - but only 750cfm. I can live with it though.
10-25-2016, 03:37 PM
#5
Team Owner
Problem with that is that the carb body is given a final zinc plating, then given a dip in the chromate protective coating that was applied. The acid tank use likely removed all of the chromate and probably removed some or all of the zinc plating. Thus, there is little...or NO..protective coating left on the bare carb body. And that coating is as important on the inside of the carb as it is on the outside.