VO system set-up

[87wolfsburgedition]

So I have ran on WVO in my RV for about 4 years now, but have never done an install. I am designing a two-tank system for my 87 Vanagon that I am in the process of switching out the gas to a 1.9td.

Have any of you guys doing VO chosen not to heat the VO tank? I was reading a thread on the frybrid forum (and many others as well) about how heating the VO tank actually speeds up polymerization. Yet the Frybrid kit has a tank heater and so does every other kit I have seen.

There are so many opinions and theories out there on VO I'm not sure which one to go with. Here is a rough sketch of my planned system, tell me where I've gone wrong (I live in Oregon where only seldom does it drop under 30f):

[mtran]

I am on wmo but too looong line from solenoid to injectors=too long purge.You can heat ONLY pick up in tank if you need,why dont put IN 3way as close to IP as you can,and no need to heat D, and perhaps use LP only for WVO usualy IP can pull D.How to go 3/8" for every IN line?

[87wolfsburgedition]

I am on wmo but too looong line from solenoid to injectors=too long purge.You can heat ONLY pick up in tank if you need,why dont put IN 3way as close to IP as you can,and no need to heat D, and perhaps use LP only for WVO usualy IP can pull D.How to go 3/8" for every IN line?

I'm new to all this installation stuff, so thanks for the feedback, anything helps, and seaching the forums doesn't always help because everybody has a different system and EVERYBODY'S got an opinion.

To comment on some of your discussion thread: I won't be heating the diesel because the VegTherm will be wired to only be on when the VO is. I have also read many posts on a variety of forums that have written about how the solenoids don't do well with extreme heat so I have placed the VegTherm on the other side of the first 3-way.

As for the LP / IP discussion: I'm not a mechanic, so it gets a bit confusing. Would I put the LP on the VO side of the 3-way so that it pushes VO through the solenoid? How can I isolate the LP to only WVO?

[mtran]

LP-lift pump ,as I read it`s beter to push than pull.
do you know http://biodiesel.infopop.cc/eve/forums and http://www.burnveg.com/forum?
Some el.valve are good,some aren`t even same manufactured,too many O ring rubber,temp up to 65c SHOULDN`T be prob but.
I also after el.valve go to manuel 3 way manuel,but el is fancy.

[87wolfsburgedition]

LP-lift pump ,as I read it`s beter to push than pull.
do you know http://biodiesel.infopop.cc/eve/forums and http://www.burnveg.com/forum?
Some el.valve are good,some aren`t even same manufactured,too many O ring rubber,temp up to 65c SHOULDN`T be prob but.
I also after el.valve go to manuel 3 way manuel,but el is fancy.

Thanks mtran.

Here is my updated design based on your suggestions about the LP and moving the solenoid closer to the injection pump to reduce purge time:


Where should I loop the VO return? Before or after the lift pump?

[mtran]

Hard to write for me man,do you know setup with 3 time 3 way valve.Remmember than start purge wvo MUST go to only wvo tank.
Cetch 22,what to do with wvo when drive on D,LP will pump yes,there will fuel go? that is plase there I put ONLY el valve(ordinary one) to bypass to tank.Better will be to move wegtherm(or better another one ) close to 3 way valve before IP(you say manuel swich),so put as much temp as you can as you use wvo.
Advise,put led or something with DIFFERENT color ,you will need on start use of this setup.
Find Sun Wizard post on burn,that man as I know ivented use of CF,his father is disel mechanic so,nobody can tell you everything in one post you must READ a lot of to know that you dealing with.
Wau for me.Best

[greg lousy]

First off, I have a solonoid valve in the hottest and latest possible point in my system - no problems as of yet. (2 years)

I don't see a flat plate heat exchanger in your diagrams. There's more than one way to heat vegetable oil, but FPHE's are probably the most tried and true. My system goes FPHE - solonoid switch - IP _ injection line heaters - with the FPHE as close to the IP as I could get it. The line heaters are there to compensate for any heat loss that occurs in the IP. When people say there is usually no need for a vegtherm, they are probably assuming the presence of an FPHE. Are you planning on utilizing your coolant at all? Electric heat can, of course, work but if thats your only heat source you will probably need more of it, and there is the danger of burning the veg. It seems difficult when you've already got coolant, heated to about the right temperature with a built in pump. Thats why these two tank systems have evolved to utilize coolant primarily.

About heating the tank. - You are right about polymerization, but you can have a heated fuel pick up without heating the whole tank. The idea is just to get the temperature of the veg being pumped up to at least 70 or 80 degrees (farenheight) so that it will flow well. Polymerization is an issue only when the veg is heated significantly more than this repeatedly.
You are going to want some kind of heated fuel pick up. Florida - maybe not, Oregon - yes.

I don't have any additional pumps, but I would recommend looping the veg return line as late in the line as possible - maybe just before the filter - some even tee in after the filter. This would be better for a few reasons and it would be easy to change if it creates problems with your flow.
If you haven't bought it yet, I might even wait and see how your system does without an additional lift pump, especially if your tank is going to be close to the engine, as it could be in a vanagon.

[87wolfsburgedition]

First off, I have a solonoid valve in the hottest and latest possible point in my system - no problems as of yet. (2 years)

I don't see a flat plate heat exchanger in your diagrams. There's more than one way to heat vegetable oil, but FPHE's are probably the most tried and true. My system goes FPHE - solonoid switch - IP _ injection line heaters - with the FPHE as close to the IP as I could get it. The line heaters are there to compensate for any heat loss that occurs in the IP. When people say there is usually no need for a vegtherm, they are probably assuming the presence of an FPHE. Are you planning on utilizing your coolant at all? Electric heat can, of course, work but if thats your only heat source you will probably need more of it, and there is the danger of burning the veg. It seems difficult when you've already got coolant, heated to about the right temperature with a built in pump. Thats why these two tank systems have evolved to utilize coolant primarily.

About heating the tank. - You are right about polymerization, but you can have a heated fuel pick up without heating the whole tank. The idea is just to get the temperature of the veg being pumped up to at least 70 or 80 degrees (farenheight) so that it will flow well. Polymerization is an issue only when the veg is heated significantly more than this repeatedly.
You are going to want some kind of heated fuel pick up. Florida - maybe not, Oregon - yes.

I don't have any additional pumps, but I would recommend looping the veg return line as late in the line as possible - maybe just before the filter - some even tee in after the filter. This would be better for a few reasons and it would be easy to change if it creates problems with your flow.
If you haven't bought it yet, I might even wait and see how your system does without an additional lift pump, especially if your tank is going to be close to the engine, as it could be in a vanagon.

Greg - Thank you for the feedback, that was what I was looking for.

So last week I reconsidered and purchased a Hot Fox tank heater / fuel pickup. I am using coolant heat with the filter head, which I ended up purchasing from WVO Designs (and now the Hot Fox too).

My design has changed slightly from the above diagram. From what I have heard / read, the LP does a better job pulling and the IP does a better job pushing. That way, if the LP pulls from the tank the system should be fully primed and not get air bubbles. I'm not sure if my IP can pull (which it does better pushing rather than pulling) the VO from the tank, and through the filter without getting an excessive amount of wear, so a LP might save the IP over the long run, right?

I have also heard that looping after the filter is a good idea because it will save your filter. Many would say that you can't filter too much, but the heat and waxing is the problem, not filtering. The filters are 10, maybe 5 micron. I'm filtering my WVO down to 1 micron before I ever even put it in my tank. The fuel filter is just a safety in case garbage is in the tank.

My system now goes:

tank
Hot Fox tank heater / pickup
Coolant heated filter block
filter
LP
VegTherm
Solenoid
Injection Line Heaters
IP
Injectors

I've already pulled the trigger and purchased all this stuff, not sure I want to drop another $200 on a FPHE. We'll see how it does and reevaluate.

[greg lousy]

I think a hotfox type fuel pick up is exactly right - they are not designed to heat your whole tank.

About the lift pump - could be a good idea. You may have noticed that there is not concrete answers to a lot of these issues. I'd love to see some statistics on failure rates of different IPs in WVO systems, but there are none. Welcome to the world of vegetable oil - 10,000 opinions for every fact. I try to only offer my own experience. My IP seems to do fine, and my veg line offers much more resistance than yours probably will, especially if the tank is above the engine, in the back - in which case gravity will help. Priming the line has caused me much less problems than I had been worrying about. Of course, my tank is in the bed so I've also got gravity on my side.


I didn't know you had already bought all this stuff. Your right - might as well set up, measure the temp. and see where your at. If it does come down to a FPHE, you could probably do a little better than $200 - A 20 plate FPHE would be plenty, 16 might even be OK, especially if you still used the vegtherm.

I think the same way about filters. i go down to 1 micron (absolute). In the caddy, I only have a small in-line filter, just after the hose in hose, so the veg is already fairly heated, and I avoid using more coolant line, as I've already got my coolant traveling all over creation.