My fuel pump failed recently. The mechanic at bugformance in Sunnyvale informed me that it was clogged with fatty goo and that the seals had been completely corroded to the point where it could no longer support the necessary pressure. He pointed the blame squarely on the use of biodiesel, as did another mechanic (got a 2nd opinion). He suggested I introduce some kind of pre-heater into the mix so as to avoid the congealed mess in my pump.

car: 2001 VW Jetta, 60k miles, the last 30k were on b100

fuel location: wester states in San Jose, CA

Franky, I've become a little disillusioned with biodiesel. I strongly suspect that is what caused the pump failure, a $3,000 fix btw, and yet no one seems to point that out on any kind of intro to the fuel. I have read a lot of conflicting information in forums about exactly this. Some people claim that no mods are necessary and that the fuel itself is to blame for any pump failures. Others seem to say that any mix of the fuel will eventually cost you a lot in repairs.

Has anyone else been fueling up at western states for over 30k miles? Is there anything I can do or are we all just kidding ourselves?

Just to be clear, you  mean the injection pump I think. It would not be the first time I have heard of problems with Western State fuel. Did you ever test the fuel with a 3/27 test?

Correct. I mean the injection pump; sorry about the confusion. No, I have not performed that test. I asked to see their ASTM paperwork and it was current... not that I'd know the difference if they were lying to me.

If biodiesel isn't stored properly, it will absorb water. It simply LOVES water and water + metal = rust. That being said, if the pump was full of congealed junk, that tells us that the biodiesel wasn't high quality to begin with.

Thanks for the input. As an update I decided to try Good Guys Biodiesel in Campbell. For those not familiar - the guy that runs it sells biodiesel and is a mechanic. I had him install a 2 micron fuel filter and everything has been smooth so far with the fuel I got there. It's stored above ground as opposed to the stuff at Western States. Word on the street seems to be that WS fuel is pretty sub par, so maybe that was my problem all along. I'll be sure and post any issues I run into.

It's very easy to test the fuel yourself.  A 3/27 test will give an idea of how well reacted the fuel is, and you can mix some of the fuel with water to see if there is any residual soap.  Both unreacted glycerides and soap can create deposits and plug filters. 

i'm new to this area, but have been interested for years.  started out reading a book byJoshua Tickell called "FROM THE FRYER TO THE FUEL TANK".  on page 39 and 122 he refers to the tendency for the alcohol in biodiesel to deteriorate rubber.  he recommends replacing certain rubber parts with a flouroelastomer synthetic, specifying a brand name Viton.

 hope ot helps

Dumbledore:

If biodiesel isn't stored properly, it will absorb water. It simply LOVES water and water + metal = rust. That being said, if the pump was full of congealed junk, that tells us that the biodiesel wasn't high quality to begin with.

This actually sounds a lot like two problems coming together: water from poor storage or lack of proper drying, combined with soap left in the fuel. That glop in the FIP is a telltale sign of soap emulsion. Note: a filter won't really help with this, although it may appear to, as this is a problem that develops over time, and won't clog a filter (that's why it ends up being a problem).

While the 27/3 test is helpful for determining conversion, I would recommend the even simpler "shake 'em up" test to determine if there is too much soap in that fuel. Take a clean, dry jar and fill it half with the fuel in question, and half with distilled water. Shake it up, sit in on the windowsill, and let it settle for a while. You'll know if there's too much soap by a white interface between the fuel and the water, plus cloudiness in the water.

Many things about offspec biodiesel can cause goo in the fuel filter, it's not just soap. Most of those things won't turn up on the 'shake-with-water' test.

robadixon:

i'm new to this area, but have been interested for years.  started out reading a book byJoshua Tickell called "FROM THE FRYER TO THE FUEL TANK".  on page 39 and 122 he refers to the tendency for the alcohol in biodiesel to deteriorate rubber.  he recommends replacing certain rubber parts with a flouroelastomer synthetic, specifying a brand name Viton.

 hope ot helps

Biodiesel is a solvent and will deteriote many types of rubber; it's not because of alcohol -- there is no alcohol in biodiesel.

 

girl Mark:

Many things about offspec biodiesel can cause goo in the fuel filter, it's not just soap. Most of those things won't turn up on the 'shake-with-water' test.

That may be, but how many things will cause goo in the fuel pump, and of those things, how many are common in commercial fuel? A picture's worth a thousand words, but barring that, I've seen enough to think that this sounds like a soap emulsion issue. You're welcome to disagree, but at this juncture, without more information, I'm curious what that disagreement would be based on.