Ok, so here we go.
These are the parts youll need.... plus a bottle of some sort. I used an empty gatorade bottle. Something that holds 500-750ml should do well. Starting in the upper left we have the Power Service Diesel Kleen additive, below that are a pair of pliers (handy for spring clips, and for getting off stubbern rubber hoses), a screwdriver for installing and removing hose clamps, and three lengths of 5/16in fuel line (the low pressure carb stuff is just fine, and about 1/8th the cost of the line for fuel injected setups). Hind sight being what it is, i would reccomend two lengths of about 28-30in, and then one length of 30 in, with a lawn mower fuel filter installed somewhere in the middle. I also made use of two double male 5/16th in fuel line adaptors.
This is the additive i used to do the diesel purge. Available at my local Advance Auto Parts, was around $7.50
Youll need to locate the fuel return line, shown here being pointed to by a screwdriver. My truck had a pinch clip, needing a pair of pliers to remove. all other hoses had hose clamps.
Next locate the fuel line that goes from the fuel filter to the IP (Injection Pump), it is the lower of the two soft line connections on the right hand side of the fuel pump. The line that exits off the left side is the vent drain, for venting air from the fuel system at the filter by using the screw cap on the top (see next picture).
The air vent is the black round cap, with the X cast into it near the upper left hand corner of the filter. Unscrew to release air from the system, screw in to seal system back up. DONT unscrew all the way, its not necessary.
Now, the first step is to disconnect the line from the filter to the IP. set aside the IP side of the line, and connect a 30in section of fuel line to the nipple on the filter. This line will go down to the return line to the tank.
The hose going across the top of the pic, and then turning down is the 30in line from the fuel filter output. It connects to the soft return line to the tank via a double male fuel line adaptor. You can see the difference between the new black fuel line, and the old gray one, that has the snap clip on it. The screwdriver is pointing to a second 30in fuel line, connected to the now open end of the hard return line.
Congratulations, youre halfway there. You have now made a close loop system that is pumping the fuel from the tank, up the frame, to the lift pump, up to the filter, and then back down to the return line to the fuel tank. This allows you to perform this service, without getting the entire fuel system full of air, and greatly aids you in restarting the engine afterwords. It also avoids making the mess i made before by leaving the fuel filter output open and having the lift pump connected.
Onto the other side of the system....
youll now have a closed system on the lift pump and fuel filter. And a hose with an open end coming from the hard return line from the injectors and IP.
now install the fuel line that has the fuel filter in it. You will use the second double male fuel line adaptor here to connect this line to the soft line that leads to the IP. Youll note that this line also has an open end.
Take the two open ends of hose, and stick them in your bottle of additive. It is critical that the line with the filter is submerged, the return line does not have to be.
At this point you should have two closed loop fuel systems, looking like this on the passenger side of the engine bay. Loop 1 - is the fuel tank, frame line, lift pump, fuel filter, and soft return line. Loop 2 is the gatorade bottle, fuel line, IP, Injectors, hard Return line, fuel line.
to Recap....
The line being pointed to with the screwdriver, comes out of the gatorade bottle filled with additive, and is connected to the soft fuel line pulled off of the fuel filter, which leads under the intake manifold to the IP.
This line is connected to the output of the hard return line behind the alternator, and empties back into the gatorade bottle.
and THIS line connects the ouput of the fuel filter to the soft return line via a double male fuel line adaptor.
when you see this, while the engine is running, and there is no fuel being sprayed anywhere else, youll know you got it right.
NOTE - in these pictures, sharp eyed wrench spinners will note a lack of hose clamps.... youll want to remedy that for your application. Use a hose clamp on EVERY fitting in this process, otherwise youll get leaks and a mess.
NOTE - you may want to attempt to "prime" the additive fuel lines, mostly by filling the lawn mower in-line filter, otherwise it will take some time, and quite a bit of engine cranking to pull the additive out of the gatorade bottle and up the fuel line to the IP. But be patient, it will happen. Cranking time is negligable once you finish the service and hook the regular fuel lines back up again.
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