wvo fuel flow

[dakota3c06]

My 85 300d is set up to run WVO. I have a two tank system, hih, 2 3way valves, plate HE in front of IP, HE in wvo tank, heated filter in trunk and aux pump after the filter. My question is about the fuel connection. I teed into the diesel line between the diesel filter outlet and IP, rerouting to my 3 way valve. Works fine. When I switch to WVO, I get diesel returning to my wvo tank, not grease. I am going to use some dye to see if grease is flowing to the IP. I do not think it is. So, my question is, did I tee off the correct diesel line to my 3 way valve or not? I was stupid and tired, I should have used dye before jumping to wvo. I used the same set up on a vw rabbit with good results. Any ideas? Maybe a bad 3 way valve or electrical connection. I will double check those in the morning.