Vegetable Oil SVO WVO waste cooking oil as biofuel

[hayduke]

I'm doing a system almost exactly like sun's on my 97 dodge, but I'm thinking I might be able to do a looped return like chris from frybrid's easily as well.

I'm using the manual valves instead of solenoids. I already had one 4 way valve (1 in 3 separate outs) laying around, so my previous thought was to just cap one of the outputs off, but what If I use the 4-way valve on my return side to have 1) return to diesel tank, 2) return to veggie tank, and 3) return to just after my veggie filter (my looped return)? I don't see any reason it wouldn't work, but I wanted some input before I do anything too rash.

Also, a little help on how to deal with the tee off the return line just past the injectors that goes to the diesel filter would be appreciated, since I still don't understand exactly where that needs to tee back into the system.

[SunWizard]

I already had one 4 way valve (1 in 3 separate outs) laying around, so my previous thought was to just cap one of the outputs off, but what If I use the 4-way valve on my return side to have 1) return to diesel tank, 2) return to veggie tank, and 3) return to just after my veggie filter (my looped return)? I don't see any reason it wouldn't work, but I wanted some input before I do anything too rash.

Yes that would work, but I have never needed a return to VO tank in the >2 years I have used it. It would provide no benefit since I am always looped on VO. I return to diesel tank to clear any air after a filter change.

Also, a little help on how to deal with the tee off the return line just past the injectors that goes to the diesel filter would be appreciated, since I still don't understand exactly where that needs to tee back into the system.

The injector drain is a return and tees into the IP return anywhere you like before your valve. From my conversion page:
Note in the diagram, you have to cut the existing injector drain manifold (small line) going into the top of the stock fuel filter and cap that line, and tee the injector drain line into the IP return line, so the small amount of VO in there gets sent back to the proper tank. Also see the diagram for a visual of the returns.

[WD8CDH]

The third position, return to VO tank, is actually a good idea. It would allow you to purge back to the tank directly rather than back flowing thru the veggie filter. While some people like to backflush their veggie filter, many filter elements can't handle the reverse pressure and can become damaged.

My looped return systems use a third 3 way solenoid to perform the function of your 4 way manual valve for a direct to vo tank purge.

[grimey]

im also using a 4way manual valve.
seems like it will work fine. im in the process of hooking it up.

[grimey]

the 4-way manual valve worked great.
i just completed a 20,000 km drive across canada and back and used a 4way valve for my returns in my sytem. no problems.

[rkpatt]

Any suggestions on where to purchase a 4 way manual valve ? - Thanks

[grimey]

i got mine from a store called West Marine. im in british columbia though, not sure if they have em in the US.

[Johnno]

I don't have a 4 way valve as such but use 4 solenoids for my return fuel (a 5 way valve equivalent)
What are they for?
1. diesel loop
2.vege loop
3. diesel flush, back through FPHE and vege filter to veg tank via inlet pipe.
4. diesel return to diesel tank (rarely used but for running tanks of diesel only)
Works well for me and my diesel stays pure so no problems with gunk.
Johnno