fuel rail question
Thread Starter
Racer
Joined: Oct 2001
Posts: 345
Likes: 8
From: Palatine Illinois
fuel rail question
If I take the feul rails off to change injectors for example, and the fuel rail gets emptied of gas, when I reconnect the fuel line feed, how does air get bled out of the rail? Do you somehow bleed it?
I could see how air could become trapped in the rail
Anybody have any insights?
Thanks
Alex
I could see how air could become trapped in the rail
Anybody have any insights?
Thanks
Alex
Instructor
Joined: Sep 2006
Posts: 159
Likes: 0
From: Rantoul IL
Thread Starter
Racer
Joined: Oct 2001
Posts: 345
Likes: 8
From: Palatine Illinois
So where does the air go? I can see some of it getting expelled through the injectors (causing a sputter).
The stock fuel rails are basicall a cyclinder laid on its side. Can you picture air pockets or bubbles that form on the top part of the cylinder, where even though there is gas coming in, the bubbles kinda remain due to the air pockets/bubbles are lighter than the fluid and thus will always go "up" (the injector orafice is about 1-2 inches below the fuel rail cylinder axis)
Kinda like a hydraulic brake system....there is a reason your brake bleeder screws are at the top of the chamber that houses the fluid in the caliper.....
If bubbles are an issue in a brake system, why arent they a concern in the fuel system.....
Im just looking for a scientific explanation, thats all.
thanks
Alex
The stock fuel rails are basicall a cyclinder laid on its side. Can you picture air pockets or bubbles that form on the top part of the cylinder, where even though there is gas coming in, the bubbles kinda remain due to the air pockets/bubbles are lighter than the fluid and thus will always go "up" (the injector orafice is about 1-2 inches below the fuel rail cylinder axis)
Kinda like a hydraulic brake system....there is a reason your brake bleeder screws are at the top of the chamber that houses the fluid in the caliper.....
If bubbles are an issue in a brake system, why arent they a concern in the fuel system.....
Im just looking for a scientific explanation, thats all.
thanks
Alex
Melting Slicks
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
Its just nothing like a brake system. the air gets pushed into the cylinders probably before the engine even starts (while cranking). The cylinders are filled with air and fuel anyway, so its not going to cause a problem to have this happen for a one split second once in a great while in the life of the engine.
You could try pushing the pressure relive valve if you feel like it will let some out, but its really not a concern.
You could try pushing the pressure relive valve if you feel like it will let some out, but its really not a concern.
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
Don't sweat it. The air is quickly purged by the pump as you start it. I have changed injectors and had the fuel rail off with no noticeable effect.
http://forums.corvetteforum.com/c5-g...r-upgrade.html
http://forums.corvetteforum.com/c5-g...r-upgrade.html
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski