what's up with my disappearing diesel fuel?

[TravelingMan0491]

So back in the week of July 4, 2012 I installed a golden fuel WVO system. Works great but recentlyI've noticed that my fuel guage would hit the "Full" mark at around 75-80 miles whereas before I would see 125-130. What I did notice is that while I'm on my WVO system, the diesel guage overtime creeps lower and lower so this leads me to believe that my diesel fuel is not making it's way back to the diesel tank. I have since moved back to Hawaii under Marine Corps orders and while here in Hawaii, I do remember a few times where I have forgotten to purge the system of the WVO before parking for the night. Could I have clogged up some of the return lines that go from injector to injector or maybe even the main return line that goes back to the diesel tank? I also noticed that rockauto doesn't carry the front feed/return fuel lines that are ahead of the lift pump unless they are called something else. Where is a good source or should I just go straight up rubber lines and cut the metal hose on the old front return line? I also do not notice any fuel puddles under the truck but not sure if it happens while driving.

Truck is a 94 Chevy K2500 extended cab 4x4

Thanks everyone!

 

[ak diesel driver]

probably just the guage/sending unit, mine has done the same thing over time. I lived in Kaneohe for about 6 months while I worked on a tunnel on the Like Like.

 

[Burning oil]

If the valving is not set up right or is not working correctly you could be returning diesel to the WVO tank & vise versa.
I had my brother pick me up from the airport once in my truck, he did not know how to switch the system correctly. He ran out of fuel because it all pumped into the other tank. Luckily it did not overflow.