I just thought I'd post this in case anyone else ever has this problem. My JD 3032e started dying intermittently, would restart, run well for a while, then die again. I cleaned the fuel separator, installed a new filter, and added some diesel fuel treatment. This helped for a few months then the problem got worse. I knew already that microbes can grow in diesel so I suspected that they were clogging the tank pickup tube. I'd noticed some sort of slimy mass in the fuel separator when I'd cleaned it before so this seemed to make sense. I started to pull the pickup from the bottom of the tank but it looked pretty daunting so I took a look inside the tank - too much fuel to see through. I removed the inlet hose at the fuel separator to drain the tank but got little flow. I blew compressed air back through the tank and then got good enough flow to drain the tank. I took another look into the fill port of the tank and could see a slimy mass in the pickup area and in another low portion of the tank. Although the stuff looked fragile I was able to use a mechanic's pickup tool to remove both masses from the tank (photo below). I've read that this stuff grows at the interface between fuel and water. I'm pretty careful about my fuel quality so I'm not sure how I got water in there other than from the air. She's running great now. I read on another site where someone paid a JD dealer $600 to pull the tank and clean it for the same problem. I hope this post saves someone that aggravation.
More info on bacteria and fungi contamination of diesel fuel from Wikipedia and DOW Chemical below - interesting. http://www.hpcdfuel.com/pdf/DOWfuel_training.pdf Microbial contamination of diesel fuel - Wikipedia
I deal with this problem more often than I'd like to in my shop. If you treated the fuel for this issue I'd recommend keeping an extra fuel filter on the shelf. Once this stuff starts dying it releases from whatever it's attached to and heads to the filter plugging it.
I'm finding that full fuel tanks can have fewer problems than tanks that are kept almost empty all the time. Maybe more so with petrol.
We switched from a single to a doublewall tank at work, just due to all the moisture and algae issues...and yes, stock up on filters after treating "problem fuel"! The other issue we've had is bees (wasps?)...we've had numerous issues with this...they start to build a nest in the filler nozzle, and if you don't check it before filling...they will plug up the supply line on smaller equipment quite nicely
It's actually not algae as many think. It's either a fungus or bacteria. Algae don't grow where the sun don't shine. http://www.hpcdfuel.com/pdf/DOWfuel_training.pdf Microbial contamination of diesel fuel - Wikipedia
I used to call it black algae too because that's what I was taught way back when. Now that I know differently I usually refer to it as black snot. Kinda seems to fit.
Ours was not even black...what was plugging up the filters really did look like snot! That reminds me...I need to replace the inline filter on one of the power units right now...last time I used it the filter cartridge itself was starting to collapse (clear plastic housing) and the engine was starting to sound a little funny (starving for fuel)
