Pros and cons of running biodiesel vs WVO - PeachParts Mercedes-Benz Forum

derherr65 · #1 03-08-2007, 11:56 PM

The first person that says "do a search" dies.

From my all night reading, I'm trying to work up the pros and cons of homemade biodiesel vs wvo. Having not done either personally, I expect to miss some things. Please let me know what, and how it is important.

Category - Homemade Biodiesel / WVO

Collection - restaurants & chemical supply / restaurants
The WVO is gotten the same way for both, but biodiesel requires methanol(drag strip maybe?) and KOH from a chemical supplier... neither of which are free.
Processing - settle,filter,dewater,add chemicals,mix,separate / settle,filter,dewater
Making biodiesel is time consuming and involves hazzardous chemicals. You must do the same steps as running WVO then add on the conversion process and more separation. "It takes me less of my time to dewater and filter enough oil to run 3 cars and heat my house than it takes for me to produce enough biodiesel to run one car."(WD8CDH) Biodiesel also leaves you with glycerin to dispose of. Is glycerin good for anything?
Tanks - stock tank / 2 tanks
A second tank is needed for WVO and should be heated.
Fuel system - stock / complex
Biodiesel will eat a few lines and seals. For B100 new rubber or viton is a must. WVO will introduce solenoids, switches, and duplicate lines and filters increasing complexity and chance of breakage.
Operating - stock / monitor then switch
Biodiesel runs, for all practical purposes, just like diesel. WVO must be monitored until the proper temperature is reached then may be switched on. It must also be switched off before arrival. I personally rarely drive less than 30+ miles at a time, but short drives can severly limit WVO use.
If you screw up - Dead IP / Dead IP, carbon
Biodiesel can kill your IP by chemical reaction(pitting) while WVO can kill it by mechanical stress. Cold WVO can also cause carbon deposits in the combustion chamber.

It seems to me that WVO is cheaper per gallon, but has a higher install cost. This could be offset by the fact that homemade biodiesel is more time consuming to produce. In the long run WVO should be the cheaper solution.

bgkast · #2 03-09-2007, 12:02 AM

Quote:

Originally Posted by derherr65

Biodiesel also leaves you with glycerin to dispose of. Is glycerin good for anything?

For B100 new rubber or viton is a must.

Biodiesel can kill your IP by chemical reaction(pitting) while WVO can kill it by mechanical stress.

Glycerin can be used to make soap....lots of soap...

Viton lines are not a must. Fuel lines that are in good shape (not cracked) are a good idea no matter what fuel you are using. All modern fuel injection line has a "viton like" lining (viton is a brand name)/

Pitting of the IP can be caused by improper dewatering of WVO. Not sure I have heard of biodiesel causing pitting.

justinperkins · #3 03-09-2007, 12:07 AM

yikes, I wonder how long it's going to take for this thread to reach 9-pager status

I'm a big believer in biodiesel, but there's no doubt that it will deteriorate your fuel lines. It's not a big deal though, just replace them as you find the leaks.

Veggie oil introduces lots of problems, extra work, money, retrofitting, etc...I'm not so stoked on veggie oil but I can see why some people are into it.

Quinn8it · #4 03-09-2007, 12:45 AM

I would have said it was a no brainer in favor of WVO, that was before I read up on how my single tank system is ruining my car.... having never made biodiesel, I think you have to collect, dewater and filter the wvo the same way, before making it into Biodiesel as you do before adding it to your tank on a wvo system. So i dont see how it is extra work, unless you factor in all the repairs you are destined to have from coked up injectors and over taxed IP...

derherr65 · #5 03-09-2007, 01:44 AM

Quote:

Originally Posted by Quinn8it

having never made biodiesel, I think you have to collect, dewater and filter the wvo the same way, before making it into Biodiesel as you do before adding it to your tank on a wvo system. So i dont see how it is extra work

If I understand you correctly, you're missing the part where after making perfectly usable WVO, you have to then process that WVO with heat, time, and chemicals, to turn it into biodiesel. Think of it as having to process biodiesel twice and WVO only once.

Quote:

Originally Posted by justinperkins

Veggie oil introduces lots of problems, extra work, money, retrofitting, etc.

I'm not sure I agree with the extra work and money. WVO is up front work and money to do the modification. Biodiesel is a little extra work and money for every gallon you make. That part will equal out at some point, I think.

Quote:

Originally Posted by bgkast

Not sure I have heard of biodiesel causing pitting.

I've heard that if you get the mixture off, it will destroy your IP. Too little and you get wet WVO type pitting, to much and you get alcohol washing all the lubricaton away... galling I guess. Does that sound right?

Quinn8it · #6 03-09-2007, 01:58 AM

Quote:

Originally Posted by justinperkins

Veggie oil introduces lots of problems, extra work,

Sorry I should have quoted....

Frankie · #7 03-09-2007, 03:16 AM

What happened to all the anti-Lovecraft signs? Just wondering, just got tired of bashing? BTW I'm not a fan of Lovecraft, I'm considering 2 tank system myself, Frybrid, Greasecar or Plantdrive.
Cheers.

JackG · #8 03-09-2007, 07:10 AM

The big difference between the two is the fact that the glycerin is removed from the oil in Bio. Yes, With Bio, you will have the glycerin to dispose of. WVO runs it through the motor.If the glycerin gets into and builds up in the crankcase......problems.

suburbanviking · #9 03-09-2007, 07:45 AM

Great thread, derherr65. I have been reading and researching for many months on this same topic. I have even brewed a few liters of test biodiesel. I am still on the fence though. Reducing the hazardous chemicals is probably the biggest driver for me (being a family man). WVO is looking more appealing.

.....Dan

Paulc66t · #10 03-09-2007, 07:59 AM

I have been running WVO for almost a year now. For me it was an easy choice. I experimented with several batches of Bio with some trouble. The way I look at it is that you need to invest some time and money upfront for WVO. The pay off is less work later on, less issues dealing with nasty chemicals, sourcing methanol and glycerin disposal.
Even WVO still has a fair amount of work associated with it. Its kind of like burning wood for home heat. You have to be willing to put the time in and not mind doing the work.

JackG · #11 03-09-2007, 08:29 AM

A big thing with WVO is to evaluate your car and determine how long you want it to run. The rings will start to go bad at some point in time with these motors. When this happens, fuel that is left on the cylinder walls will find itself in the crankcase, whether it is bio,dino,or WVO. If that fuel is WVO, it contains glycerin that will attack bearing etc. I plan on keeping my car for far more than another 100k so WVO is not an option for me.
If I had a rusted up beater that only had another yr or 2 left in the body, that would be a different story.

winmutt · #12 03-09-2007, 08:32 AM

buy your bio at the pump and pay your taxes....

jshadows · #13 03-09-2007, 08:40 AM

Quote:

Originally Posted by JackG

A big thing with WVO is to evaluate your car and determine how long you want it to run. The rings will start to go bad at some point in time with these motors. When this happens, fuel that is left on the cylinder walls will find itself in the crankcase, whether it is bio,dino,or WVO. If that fuel is WVO, it contains glycerin that will attack bearing etc. I plan on keeping my car for far more than another 100k so WVO is not an option for me.
If I had a rusted up beater that only had another yr or 2 left in the body, that would be a different story.

There is no glycerin in WVO. It is a byproduct of the chemical reaction between the alcohol and fatty acid (the WVO) which produces the esters, methyl or ethyl, more commonly know of as biodiesel. WVO is more or less chemically homogenous notwithstanding the sugars etc left there by the food that was cooked in it.

The lesser known of the WVO is polymerization and combustion problems which can lead to deposits in the lands of the rings. Of course there's coking and deposit problems at the injector and IP points as well being the most documented. I have yet to see a piston and rings from a long term WVO powered diesel.

firemediceric · #14 03-09-2007, 08:56 AM

Quote:

Originally Posted by jshadows

There is no glycerin in WVO. It is a byproduct of the chemical reaction between the alcohol and fatty acid (the WVO) which produces the esters, methyl or ethyl, more commonly know of as biodiesel. WVO is more or less chemically homogenous notwithstanding the sugars etc left there by the food that was cooked in it.

The lesser known of the WVO is polymerization and combustion problems which can lead to deposits in the lands of the rings. Of course there's coking and deposit problems at the injector and IP points as well being the most documented. I have yet to see a piston and rings from a long term WVO powered diesel.

This post is right on the money

Glycerin is not a factor in WVO because there is none there until it is formed by a chemical reaction. The glycol molecule that is present in WVO will not be a problem for the engine, IMHO.

People talk about using the glycerin by-product from BD for soap or candles, but do you want to use soap or candles that have methanol in them?

Look at my signature. I like what I'm doing, but living in Florida helps it work for me. By not doing a bunch of conversions to the vehicle I have less to go wrong. Read the Frybrid forum and you will always see people chasing air leaks or other component problems. I choose not to go the BD route because I don't want to deal with procuring and using the chemicals required, and I don't want to put a lot on $$$ into a processor. If my supply of WVO dries up tomorrow, I'm only stuck with a couple hundred dollars of filetering supplies.

mespe · #15 03-09-2007, 09:16 AM

JackG has a very good point. That is what I've been doing, buying a beater, driving it on WVO and then parting it. My first 300SD I drove 30K miles. about 25 of those were on BD and WVO/RUG. Had injector nailing a couple times, but it cleared up all by itself. Love these self-healing Benz's.

I would like to think that if I burned WVO in the summer and then switched over to diesel in the winter, that the WVO fuel use woulf clean the deposits from the dino fuel use and the dino fuel use would clean what the WVO left off. Would be nice wouldn't it.

Either way, BD or heated WVO you're gonna invest several hundred EXTRA dollars in parts. Either a processor and it's pumps, titration equipment, safety equipment,,,, or in a 2-tank system - a second tank (maybe) plumbing, Hose in a hose, switches, pump/valve,,,

Simply using WVO/RUG the only investment you need is a sock filter and a couple of buckets.

See my ebay guide on WVO and diesels:

http://reviews.ebay.com/Burning-WVO-Waste-Vegetable-Oil-in-Diesel-Vehicles-benz_W0QQugidZ10000000001239706

and PLEASE check the yes button.

Thanks