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Old 06-27-2006, 09:16 PM   #2 (permalink)
High Sierra 2500
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Join Date: Oct 2005
Location: Mid Michigan
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To bleed air (or old fuel) out of the system on early models (1982-1984):

Hook an air compressor hose into the return line at the injection pump (IP). The line you want is the rubber one that goes into the front of the IP. Alternatively, you can stick the air hose into the filler neck, but that is not as effective. You can also modify a fuel cap with a valve stem off of a tubeless tire and use an air chuck to supply the air, which works good. Whatever way you choose, the next step is to loosen the fitting on the outlet side of the fuel filter. Loosen it enough that fuel will come out readily, but donít take it all the way off as you will need to be able to tighten it fairly easily. Put a pop bottle with a funnel stuck in the neck under the fitting to collect the fuel. With the fuel cap on tight, turn on the air to about 4 psi. Give it some time to fill the fuel tank. Fuel will start to run out of the fitting and into the pop bottle. When the pop bottle is about full, tighten the fitting. Then turn off the air. Disconnect the air line, wait for any remaining pressure to bleed out of the tank, and then reconnect the return line to the IP. If you used the modified fuel cap or the hose in the filler neck, you can ignore these last few steps.

Once you have bled the air out of the system to that point, you may need to crank for a while to get it to start. It is not necessary to loosen injector lines to bleed the system to the injectors on the 6.2. Simply crank until it starts. You will need to do this in several cranking sessions of about 15-25 seconds in length so that you do not burn out the starter.

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