Injection pump plumbing, getting a handle on things.

In order to map out a conversion, I need to figure out how I can splice in the solenoid valves that are used to switch from diesel to vegetable oil.

I've been sending out desperate emails and howling at the moon for diagrams and descriptions of how the om606 injection pump is plumbed. Again, grease heads have come to the rescue. In particular, Ray Ackley provided me with some very helpful info and anotated pictures (link to his gallery) and also sent me links to a very helpful Frybrid forum thread.



First the fuel goes from the fuel tank to the fuel heater. (funny looking thing in the top right corner)
(1) From the fuel heater to the prefilter screen
(2) Prefilter to shut-off valve
(3) Shut-off valve to lift pump
(4) Lift pump to fuel filter
(5) Fuel filter to shut-off valve (again)

The shut-off valve feeds the injection pump through a port in behind. The injection pump sends fuel to the injectors, but also has a return line where excess fuel exits

(6) Excess fuel goes out the return line, where it meets the fuel flowing back from the injectors (7). This connection is made at a port on the fuel filter housing, where a percentage is drawn back into the filter, and the rest is sent back to the tank (8).


And here's a diagram of the "replumbed" injection pump, with 3 switching valves:


Replumbed
On diesel:
First the fuel goes from the fuel tank to the fuel heater. (funny looking thing in the top right corner)(1) From the fuel heater to the prefilter screen(2) Prefilter to shut-off valve(3) Shut-off valve to diesel filter(4) diesel filter to switching valve
(5) switching valve to lift pump
(6) lift pump to shut-off valve, which feeds the injection pump & injectors

(7) Excess fuel goes out the return line, where it meets the fuel flowing back from the injectors (8). This connection is made at a port on the fuel filter housing. The port in the housing is blocked off (indicated on diagram by the black lines) to prevent being drawn back into the diesel filter, so the excess diesel (9) is sent back to the fuel switching valve, and from tehere to the diesel tank (10).

On vegetable oil:
11) Veggie oil comes from veggie tank
12) To fuel switching valve
5) to lift pump
6) into shut-off valve, which feeds the injection pump & injectors
(7) Excess fuel goes out the return line, where it meets the fuel flowing back from the injectors (8). This connection is made at a port on the fuel filter housing. The port in the housing is blocked off (indicated on diagram by the black lines) to prevent being drawn back into the diesel filter, so the excess fuel (9) is sent back to the fuel switching valve, and from there to a 3rd valve.
The 3rd valve can either direct the fuel back to the veggie tank (14) or loop it back into the fuel supply.

Many thanks to "awmw" from the frybrid forum.

*EDIT* It should be noted that this is not the only way to replumb the IP for vegetable oil. The standard GreaseCar system for e300d's involves a very different rearrangement of IP lines. In their setup, the fuel is PUSHED through filters. More info here:
http://biodiesel.infopop.cc/eve/forums/a/tpc/f/159605551/m/5911008232/p/1