Here's the setup:

I've been using B100 from Biofuel Oasis in Berkeley in my sailboat for over a year now, and my fuel system has been clean for quite a while (cleaned the tank, new lines, new Racor 500). Last weekend I didn't have time to pick up any biodiesel, so I added 10 gallons of petrodiesel from the local fuel dock (Alameda estuary - they get tons of traffic). There were probably 5 gallons in the tank, so this mix is around B30 at this point.

After putting about 15 hours on the engine (that's about 5 gallons) I happened to look at the Racor and saw about 2" of white crystals in the bottom of the bowl. The engine is a Westerbeke 27, which uses a flow-through fuel system, so I'd guess the entire tank had cycled through the filter system a couple of times in that 15 hours. I'm running a 2 micron filter in the Racor.

What's going on here? I remember getting some of these crystals (not this much) when I was switching over to biodiesel and using up the petrodiesel in the process (I thought it was just crap from the tank), but never when it was all petro or all bio.
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Pete
online Pete
SF Bay Area
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  • Leo
    Leo
    offline 121

    Re: Filled with petrodiesel and now I'm getting crystals in the filter bowl

    Tue, January 30, 2007 - 1:31 PM
    I don't know what is going on in this partricular case. However one thing I do know is that the glue which holds the paper elemtent to the plastic part of each element on racor FH and FG model filters is alcholhol soluble thus making not a very good filter for Biodiesel use. Racor technecians recomend not excedding a B2o blend with the use of the FH and FG filter. A bit of a non-sequiter but also sort of relavent.

    Good luck
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  • Todd
    Todd
    offline 144

    Re: Filled with petrodiesel and now I'm getting crystals in the filter bowl

    Tue, January 30, 2007 - 5:12 PM
    Possible water in the diesel that you purchased. Take a sample from them and see what it looks like, you might be surprised.
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    • Pete
      Pete
      online 16

      Re: Filled with petrodiesel and now I'm getting crystals in the filter bowl

      Wed, January 31, 2007 - 3:49 PM
      So you're saying water does this to biodiesel? I don't buy it--I've had some water in that tank before (pretty much every boat has some) when I was running B100 and never got any of this stuff.

      If you meant that the combination of biodiesel+petrodiesel+water produces this, OK, but what's the mechanism that makes this different from just biodiesel+water or petrodiesel+water?
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      • Todd
        Todd
        offline 144

        Re: Filled with petrodiesel and now I'm getting crystals in the filter bowl

        Thu, February 1, 2007 - 12:11 AM
        It seemed like the likely culprit, but you should check it out. I mean if it is the last thing you put in the tank, and it recircs within the fuel system and tank, then with agitation you could generate chemical reaction with any leftover entrapped glycerins in the biodiesel. Of course, it that is the case you may have some issues with the biodiesel since it shouldn't have enough of a reaction potential to generate the sludge.

        The only other thing I could think of was temperature. And while we did get extremely cold recently, I didn't think you would still have crystals, but thinking back on it, it takes some good ambient warmth to melt the wax crystals once they form. One good test, if you have any extra biodiesel around, put some in a small mason jar and watch the effects on it when it is stored in your boat. Give you a better indication of the quality of the biodiesel you are using too.

        Try putting in some diesel anti-gel next tank and see if it helps. I would think that with the warmer weather your problem might be solved.

        Check out these links if you would like:
        www.eere.energy.gov/cleancit..._hole.pdf

        www1.eere.energy.gov/biomass...6182.pdf
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