Starting fluid is ether or some other very volatile mix, if you are just trying to get it to run without fuel, WD-40 works pretty well.
I always thought you should crack ALL of the injector lines on a mechanically injected engine to bleed air. The injector pump is usually a cam operated plunger for each cylinder. It expects a noncompressible fluid to be in the line to the injector. When the plunger gets pushed, the fluid in the line has to reach the release pressure of the injector or nothing (including the air) will get pushed through. If it's full of air, it will come nowhere close to this pressure and just bounce back. It will do this forever, even if the pump is full of fuel. If you crack only one line, all the others will still be full of air as each circuit is isolated. The injector isn't just a nozzle, it has a check valve that requires a certain pressure to open to prevent after dribble etc.
None of this is true of a common rail engine which have a 20,000 - 30,000 psi pump on the rail, and a return path for spill fuel and air.
I always thought you should crack ALL of the injector lines on a mechanically injected engine to bleed air. The injector pump is usually a cam operated plunger for each cylinder. It expects a noncompressible fluid to be in the line to the injector. When the plunger gets pushed, the fluid in the line has to reach the release pressure of the injector or nothing (including the air) will get pushed through. If it's full of air, it will come nowhere close to this pressure and just bounce back. It will do this forever, even if the pump is full of fuel. If you crack only one line, all the others will still be full of air as each circuit is isolated. The injector isn't just a nozzle, it has a check valve that requires a certain pressure to open to prevent after dribble etc.
None of this is true of a common rail engine which have a 20,000 - 30,000 psi pump on the rail, and a return path for spill fuel and air.
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