Tim,

I disagree. The IP will pump a certain VOLUME into the injector lines whether there is air in them or not. The air will be pushed thru the injectors when it is compressed enough that the pressure is enough to pop open the injector, just as the fuel does. If the air is compressed enough, it will become a liquid.

P E H

Not at the pressures and temperatures that are going to be present in your engine.

Assuming the IP is a (variable) positive displacement pump, I would expect that it should take 'x' strokes to fill the high pressure line with liquid, depending on the position of the rack and its corresponding volume per stroke.

Once filled, I would expect pressure in the hard line to rise to the 'pop' pressure of the injector and then stay relatively constant as fuel is injected in the line entered the pre-chamber.

Air in the line can either get out of the way, via popping the injector, or be compressed while resisting and exit along with the liquid.

Eventually, I expect all air to be expelled and only liquid to be injected.

Jim H,

That's exactly how it works whether the injector lines are closed or cracked open.

Its quicker to not open the injector lines and just start the engine because you don't have to stop and look for leaking fuel and then try again and when the fuel finally comes out, tighten the injector lines.

Actually, you don't have to do anything to bleed the system except put 2 gallons fuel in the tank and crank the engine on the 603 engine. On the older engines with the hand pump, all you have to do is work the hand pump. No need to loosen the filter screw. There is a bleed hole in the top of the filter that will let the air out of the filter.

P E H