By: Karl Denninger

Here we go again!

A couple of years ago I wrote an article I called the "Snake Oil Chronicles", detailing my experience with the Algae-X "fuel conditioners."

Now I've been asked what I might think about the "Diesel Tex" units, which purport to do the same thing...... so, two units in hand, I have accepted the chellenge under the same terms, specifically:

Diesel Tex can be found on the web at; here is a picture of the various units available:

Fair warning and disclosure - I do not work for DieselTex in any capacity, and have no financial interest in the company.

My methodology of testing will be as follows:

The configuration of the fuel system and specifics of the test environment are:

Here's the chronology, recorded as each event occurs, and documented with photos when appropriate...

8/26/2004 - Installed one DieselTex 503 unit in the forward RACOR feedline for each engine. Each is an apparently solid block of aluminum with a clear "parting line" in one end; the manufacturer claims that they cannot be disassembled, however. The units were installed without incident requiring only one 1/2" pipe nipple in addition to the plumbing already on the boat. The installation is definitely "temporary", as you'll see from the pictures to follow - if I keep 'em, they're going in permanently mounted right on the RACORs.

9/1/2004 - Have run two trips. The port engine was the one which won the "coin toss" when the installation took place, and thus, it is the one which is enabled. The Starboard engine is running without the unit inline. There is a MARKED difference - much larger than I saw with the Algae-X units (!) I didn't expect this, but here's the evidence for you in living color...

PORT Engine (unit ENABLED):

Note that there is some darkening of the element, but not a whole lot.


This element is black, as were BOTH when they were changed before the test began.

10/31/04 - The boat has not been run all that much, due to Ivan. We have had to run away from the storm, run back, and then put on a couple of trips since in the gulf - but no major operating hours. Total operational hours on the motors in the last two months as less than 20 - which is unfortunate, as it should be expected to color the results.

Oh well, I promised to report what I have, and here 'ya go. Here are the port and starboard filters at present - remember, port has the unit enabled, starboard has it turned off. Both filters are, to the eye, equally fouled at the present time, but neither shows enough restriction to justify a change of the elements.

Port filter


Developing as evidence continues to build..... hopefully we can get enough hours on the filters and units in the next few months to draw some valid conclusions, and don't end up waiting until spring....