Grey crud in fuel filter?

[fields_mj]

Changed my fuel filter tonight. Last time I changed it was last November. I'm surprised I had to change it again so soon, but I also re-did my fuel pick ups on the front take last October. Tonight, the cap on the bottom of the filter had some gray sludge built up in it. Not a lot, just a little. I scrapped it out with my pocket knife, and rinsed the cap out before I put it back on. It had the consistency of paint sediment. There was only maybe a teaspoon full. Is this normal?

Just curious,
Mark

 

[MIDNIGHT RIDER]

Without actually seeing the crud with my own eyes, this is merely educated speculating; but, from how you describe that you recently re-worked the tank pick-ups, I am gonna surmise that the grey crud is fuel-tank "algae".

Although commonly mis-named "algae", it is not really algae, as algae cannot thrive without genuine sunlight, the more sun the better.

What it really is is a bacteria that lives in darkness on the interface between the fuel layer and the water layer.

After a few years, it builds into a "mat" that just sort of floats and sloshes around close to the tanks bottom.

Any time you mess around with the internals of the tank, or add fuel, especially when the fuel-level is quite low, it disturbs this bacterial "mat", dislodging chunks of it that get sucked into the fuel system.


Anyway, that's my theory.

 

[jim_22]

That or you added bad fuel... good news is the filter did its job.

 

[The Warden]

I thought that "algae" in the fuel tanks would show up as a black substance?

 

[Chevyboy_0]

ohter then drop the tanks and clean them really good, what else can we do to kill the "algae"

 

[towtruckdave]

To kill the algae, drink several beers and then *** genorously into the tank. Then drive at high speed around a motocross track until you need to go *** again.

Or you can by an additive that kills it from the truck parts store.

 

[RLDSL]

Kill-em That stuff will take care of your tank problem and kill the critters. It/s costy, but one bottle will last a very long time.

 

[Death85e]

My understanding is that if you are using the diesel in your tanks frequently then algae growth and water in the tanks is not an issue. but if you store diesel in above ground tanks such as the ones we commonly use on farms for the tractors and they set for extended periods of time without being used then you will get the algae growth.

 

[RLDSL]

My understanding is that if you are using the diesel in your tanks frequently then algae growth and water in the tanks is not an issue. but if you store diesel in above ground tanks such as the ones we commonly use on farms for the tractors and they set for extended periods of time without being used then you will get the algae growth.

Or you can just fill up at a station that has contaminated storage tanks, or if you let your truck sit for an extended period for whatever reason without treating the tanks first, it can happen.

When I had to yank my engine for freeze plugs and tore it down while I was at it, I remembered to treat one tank before parking it, but somehow managed to forget the other and after it sat a few months, first run out I went to switch tanks and I very quickly got a restriction light and the screen on my pump bowl was clogged with critters, so it doesnt take much to get overrun with the little beggers.

 

[Death85e]

Or you can just fill up at a station that has contaminated storage tanks, or if you let your truck sit for an extended period for whatever reason without treating the tanks first, it can happen.

When I had to yank my engine for freeze plugs and tore it down while I was at it, I remembered to treat one tank before parking it, but somehow managed to forget the other and after it sat a few months, first run out I went to switch tanks and I very quickly got a restriction light and the screen on my pump bowl was clogged with critters, so it doesnt take much to get overrun with the little beggers.

My apologies i often forget that aspect of it since i fill up my tanks at a truck stop that has new diesel brought in several times a week due to the large volume.

 

[gatorman21218]

Biobor JF is what we used to run in our boats. Marine environment is much more prone for algae than trucks so its bound to work on trucks even better. http://www.amazon.com/Biobor-Jf-16oz-Growth-Control/dp/B0014434DG

 

[fields_mj]

Okay, here's where I say something stupid. When I treat the tanks, and it kills the bacteria, does that mean that on the next tank, it will all get sucked into the fuel filter again?

I drive the truck about every day. I generally fill up each tank about every other week. The PO didn't hardly drive it at all. I expected lots of problems when I re-did the front tank pick ups (haven't gotten to the rear yet). Actually, I expected to have even more problems sooner. I just wasn't sure what I was looking for. I too had heard that the bacteria was black, and since this stuff was gray, I wasn't sure what it was. Like I said, it looked like gray enamel paint sediment that had solidified in the bottom of a coffee can full of mineral spirits. When I pulled the filter, I did notice that the fuel in it was just a little cloudy when I shined the flash light down in there.

 

[RLDSL]

Okay, here's where I say something stupid. When I treat the tanks, and it kills the bacteria, does that mean that on the next tank, it will all get sucked into the fuel filter again?

I drive the truck about every day. I generally fill up each tank about every other week. The PO didn't hardly drive it at all. I expected lots of problems when I re-did the front tank pick ups (haven't gotten to the rear yet). Actually, I expected to have even more problems sooner. I just wasn't sure what I was looking for. I too had heard that the bacteria was black, and since this stuff was gray, I wasn't sure what it was. Like I said, it looked like gray enamel paint sediment that had solidified in the bottom of a coffee can full of mineral spirits. When I pulled the filter, I did notice that the fuel in it was just a little cloudy when I shined the flash light down in there.

Not stupid at all, and yes as it kills the critters, they will get knocked loose from the tank walls and sucked into the filter so it would be wise to grab a couple of spare filters, or even if you have rubber line before your filter, installing a cheap inline disposable and grabbing a handful of the things ( if I'm not mistaken, those mercedes diesel primary filters are the right size and serve just such a purpose, lots of places sell them in multi packs ) that way you can pitch the cheap pre filters and keep the more expensive main filter in place longer

 

[MIDNIGHT RIDER]

If the truck is over ten years old, and the tanks haven't been out from under the truck and over-hauled/cleaned, then regardless of how particular you are about your fuel purchases, you most likely have some problem with fuel bacteria.

Humid areas, like Kentucky, are worse for it; dry or very cold places are less likely to be bothered with it.

A few years ago, I started having an episode where every few days the pre-filter would be over-whelmed with a big slug of the stuff, shutting me down wherever I happened to be; not the end of the world, but very annoying and very possibly dangerous.

I started researching every source I could find about the problem and the general consensus was that if you really do have a bacteria problem, none of the tank additives are gonna cure it.

What happens is the additive kills a portion of the bacteria and the few survivors multiply exponentially while thriving on the carcasses of the ones the treatment killed.

Also, the dead bacteria forms into big clumps that continually get sucked into the system, thus clogging things up.

The only fix that worked for me was to install a barrage of sediment-bowls, water-separators, filters, and a genuine New Zealand DE-BUG unit.

Since adding the DE-BUG unit and sediment-bowls, I have not had a fuel stoppage issue.

I have found plenty of evidence in the sediment-bowls where it settles out and can be disposed of.

The main fuel-filter and the pre-filters last almost forever since installing the DE-BUG, so I am satisfied that it does work.

At the head of the creek is a GoldenRod unit through which every drop must pass before proceeding anywhere else and it pays it's keep for certain.

 

[MIDNIGHT RIDER]

I too had heard that the bacteria was black, and since this stuff was gray, I wasn't sure what it was.

The bacteria will exhibit itself in varying colors according to region and just which particular bacteria is prominent within the fuel.

Also, live bacteria will be colored different from dead bacteria.

The crud that was lodging in my clear inline pre-filters looked like chewed up bits of not hardly cured tobacco leaves that had been hanging in the barn only a few days, sort of brownish-green.


I am a firm believer in those simple cheap see-thru plastic in-line filters.

I buy them out of a barrel at swap-meets, 3/8", three for five-bucks.

Installed ahead of the lift-pump, they catch all of the bigger trash that would otherwise clog the much more expensive main fuel-filter.

Instead of laying under the truck, or hanging head-down under the hood, trying to replace one of the inline pre-filters, I route a "loop" of fuel-line to a much more accessible location and install the pre-filter there, where I can change one out without getting my Sunday-go-to-meetin' clothes dirty.


Filter manufacturers know that, if they would allow for a deep bottom reservoir, the filter media would last for a very long time without clogging.

That is why they build the canister merely a 1/16" or so outside of the pleats and no room at the bottom whatsoever, so that the least little bit of crud will immediately clog things up and require you buy another filter.


Get yourself one of those clear see-thru GoldenRod units and you will see just how a fuel-filter really should be built.

They have a very roomy deep see-thru housing, a bottom drain-****; and, the outer housing can be removed, rinsed, and replaced, without disturbing the inner screw-on filter cartridge.

Most trash that enters the unit will settle to the bottom and stay there.

Any particles that adhere to the filter-cartridge will get rinsed loose by the sloshing of the fuel when in motion, and that too will settle to the bottom; thus, the cartridge itself will last almost indefinitely before getting plugged enough to require replacement.