Unwashed B100 - PeachParts Mercedes-Benz Forum

PanzerSD · #1 03-15-2006, 03:19 AM

What problems can I encounter by using unwashed or partially washed Biodiesel? just more frequent filter changes?

greasybenz · #2 03-15-2006, 03:23 AM

And you may have some left over glycerin which in a newer diesel is bad! But in a old benz it will take it and accept it just fine. Its always good to wash it many times i wash it 3-4times before it goes into my moms passat's fuel tank.

boneheaddoctor · #3 03-15-2006, 08:12 AM

nasties that can contribute to decreaced IP lifespan and increased wear...

Doing a proper wash is an important step.

83-240D · #4 03-19-2006, 08:58 PM

we never wash it. just pour it in. as you add fuel it will be absorned. how much damage can it do after all the bad diesel the engine has lived on for the last 20-30 years?

imagesinthewind · #5 03-20-2006, 01:39 AM

Do you allow the unwashed bio to settle for a period of time before you add it to your tank?
Do you settle in an open tank?
I went to a workshop this weekend with girl-mark and though we didn't have time to really go after some of the questions I had, one thng that I thought was as long as you settle in an open tank that allows methanol to evaporate out, the glycerin and soap should fall out. The extra meth in the bio can hold that stuff in suspension and if it evaporates you should see the nasty at the bottom of a tank (I'm going to use an open 55 gallon drum as my processor, not the water tank) and spyphon off the good clear stuff at the top.

I'm going to do one washing. Before the glycerin is even poured off.
Then i'll stir it for a while and allow the water and meth to evaporate and use the top good stuff after it clears.
I'm doing bio for the environment, using that much water to wash it goes against my conscience.

Ginny in Denver

Diesel Giant · #6 03-20-2006, 08:24 AM

Not washing it is really not a good idea. Take the extra time and steps to make the stuff right. You want the fuel as clean as possible to get out the stuff your IP does not need to deal with.

PanzerSD · #7 03-22-2006, 01:46 AM

I have a water seperator from a fairly new MCI coach bus, running the a Detroit diesel, if I install this seperator, can I then use unwashed B100?

forgive me for NOT wanting to wash my BD

imagesinthewind · #8 03-22-2006, 11:12 AM

No. At least that was what was told to us this weekend at the bd workshop. The soap and water are kind of in suspension until it reaches a really warm place like the engine. Then it's immediately out of suspension and it warms and explodes causing pitting in the cumbustion chamber. Can also happen inside the IP causing pitting there. Soap can also cause incomplete combustion and coking of the injectors and carbon build up on the chamber walls wihich may cause siezing.
I'm with you. I don't want to wash it either. On newer engines though you must. I think you can get away with it a little maybe with incomplete washing in older MBs.
Drying is really important, too. I've been using a bit of heat (propane) to separate the water then pouring off the bio leaving the water at the bottom of the container.

One other thing to try is getting all the methanol out of the unwashed bio before you begin washing. By evap or by heat. The methanol will hold the water and soap in the bio. Without it the crap falls to the bottom in about 10 days, or so I've been told. Then use just the top and you're better that if you just made and poured into the tank. But not at good as several washings.
If you use virgin oil there is almost not soap to begin with, no FFAs from heating so the soap is so small that when I washed a virgin oil batch the first wash water was almost clear.

If you can, try doing a glycerin prewash. After the agitation is complete, add water at about 5% of the amount of oil. This will help get the extra glycerin out, won't make the water go into suspension so it will fall out the bottom. It will get some of the soap out and all you'll need to do it drain off the water and glycerin and the first wash will be done.

Good luck in whatever you decide.
I don't want to wash either. Waste of water.
BUT, there is a chance that I'll begin using the 2-4 wash waste water for watering my yard this year. The yard will love the soap. I'll have to switch to potasium hydroxide to do that though.

There are many who don't wash, but they are also driving older diesels that have had the crap fuel for 20+ years.

phasmatisnox · #9 03-22-2006, 01:45 PM

My Physics professor has been helping me out with BD and has been making it for years. He never washes his- he's always had bad results with washing. He's left steel and aluminum samples in unwashed BD for months, with no corrosion, discoloration, or anything else. What other kind of materials are found in an IP? The lines looks like maybe brass.

greasybenz · #10 03-22-2006, 01:53 PM

well again in a mercedes diesel no harm done running unwashed b100. But in a newer diesel say my moms 05 VW passat TDI lots of harm can be done with unwashed bio. Thats why i always wash it 3-4 times before it goes into the TDI's fuel tank.

Higher quality fuel means better engine life and less problems.

Old300D · #11 03-22-2006, 02:55 PM

From what I hear, unwashed can be ok if it is settled and aired for a long time -- obviously it must be clear. The methanol can cause issues, it made my car idle roughly, and soap is not fuel. Settle it out for an extended period and I'm sure it can be just fine, but I'm not that patient. I can react, settle, wash and dry a batch in a weekend -- no way can an unwashed batch have that kind of turn-around unless you like burning methanol and soap.