Vegetable Oil SVO WVO waste cooking oil as biofuel

[compostbrain]

So, I am converting my 03 Sprinter which has a mechanical fuel pump after the filter. I was originally going to purchase a plantdrive kit and but after more research I am thinking of trying to homebrew more of it.

I am wondering if anyone has experience with this vehicle and can give advice on my current plan.:

Replace exisiting tank with a custom aluminum divided tank with a 5 gal section for diesel startup and heated fuel pickup(ala Sunwizard design) in the 25-40 gal veggie tank.(local welder has offered to fab this up for about $200)
3 electric valve switching system(probably plantdrive)
coolant heated fuel filter(not sure if I will purchase of the shelf or fabricate)
ftpe after filter
TIH
Also thinking of getting a controller from plantdrive as the vehicle will have multiple operators.

I am thinking I don't need an extra lift pump or a vegtherm after some research although I was advised otherwise by certain kit manufacturer.

[SunWizard]

With a FPHE you shouldn't want a vegtherm. Other details depend on your location since that determines how cold it will need to work in.

[compostbrain]

i am located in central PA. We regularly get down to between 0 and 10 degrees in winter.

[compostbrain]

My mechanical lift pump is after the diesel fuel filter. This will mean the filters will be under vacuum which is undesirable from what I have read elsewhere on this site. . How much of a problem is this? Should I live with it or is there a better solution?

[SunWizard]

My mechanical lift pump is after the diesel fuel filter. This will mean the filters will be under vacuum which is undesirable from what I have read elsewhere on this site. . How much of a problem is this?

The filters may not last as long, but no way to give a number like 20%. And you must be more careful about air leaks.

Should I live with it or is there a better solution?

You can plumb it with the filters under pressure. Its less of a benefit with your lift pump which creates much less pressure than a cummins piston style pump.

You can use 1 less valve if you add another lift pump. And your lift pump is weak so an added one is often used so you have a way to keep going if 1 fails. Since both ways have pros and cons, its not a clear choice whether its better to share the lift pump (the best choice on a cummins.)

[compostbrain]

why would I need three valves even without an extra lift pump?
My TDI only uses two...

[SunWizard]

why would I need three valves even without an extra lift pump?
My TDI only uses two...

It all depends on how you choose to plumb it. See mine and many other options in the converted vehicles section here.

[compostbrain]

getting back to this... I have been advised to send the veggie return line all the way to tank otherwise the computer may throw codes that will cause it to go into limp mode. Does anyone see a problem with this. What issues might I run into? thanks in advance for any help!

[SunWizard]

getting back to this... I have been advised to send the veggie return line all the way to tank otherwise the computer may throw codes that will cause it to go into limp mode.

Did they say what codes or why it throws them? If you knew we might find a way to avoid them. Looped is better since it provides more heat, and less flow+ pressure drop through the filter. Which means longer filter life.

[compostbrain]

Here is the quote : "If there is a loop and you let your foot off the gas it closes the solenoids to the injectors and the return fuel that is going back into the supply builds up pressure and throws a "rail pressure too high" code and throws the vehicle into limp mode.

[SunWizard]

Dang computers running everything! Here is an idea: if your looped return tees before the 1st valve or filter, as on my setup, when the injectors closed, any return flow goes back the supply line, and no pressure build up. It can't be much flow that goes back to the tank through the single fuel line, since if it were, you would be gaining free fuel out of nowhere, filling up your tank. It mainly provides relief of any pressure spike, then there is no flow after the 1st few fractions of a second in the case of long decelerating. You still get the extra heat benefits of looping.

[compostbrain]

ok I will try following your diagram. I have ordered boat valves and hope to get this thing done in the next week or so.

[compostbrain]

Do you think I will need a needle vavle or is that a unique issue with the cummins pump?

Also does anyone have a lead on best source for vaccuum and temp gauge?

[SunWizard]

Do you think I will need a needle vavle or is that a unique issue with the cummins pump?

You will need it with any pump which produces pulses. I don't know how yours works.

Also does anyone have a lead on best source for vaccuum and temp gauge?

For VO pressure and temp gauges I used cheap oil pressure and coolant temp in stock at any auto parts store which is the best source. The trick is get ones with a 270 degree sweep, which were <$20.

[compostbrain]

On my vehicle the diesel fuel return line is routed through the diesel filter. So if I use your fuel routing diagram I will have reroute the return line to bypass the filter and plug the filter housing where those lines enter? is this correct?

Also where do the 3/4 to 1/2' reducing T's that you list in your parts list go in your diagram?