Originally Posted by babymog (Post 2612167)

Water dispersed in fuel is still bad. It might run, but it is not good for the injection pump, best to remove as much water as possible before the dispersant (which is likely just alcohol).

I believe that your primary (the metal cartrige) filter also has some water-trapping capacity, change the filter after you run out the bad fuel.

Originally Posted by compress ignite (Post 2616563)

1. Other than from badly maintained fuel sources...How the Heck did water get
in your tank?
2. Almost ANY water dispersant is basically Alcohol. No. No. for Diesels.
3. Major Water Infestation...I'd DRAIN the Tank completely,Remove the Fuel
Strainer and clean the tank.

Originally Posted by paddo (Post 2626838)

Well it's been a while now since mixing in some gasoline to my diesel tank. the new inline filter has not blocked and the line seems completely clear of obstruction. so it looks as if this could be a promising treatment for diesel "algae" attacks. One case is not enough to prove much, but it would be good if a completely free treatment was successful at getting rid of this problem. In fact slightly less than free since gas is cheaper.

I still have the $40 container of startron tank cleaner and haven't used any yet, so I could see how the gas treatment went on its own. It would be a bit surprising if it worked perfectly since i think the main thing to do is get the water out of the tank, but so far it seems to have got rid of it.

Originally Posted by whunter (Post 2626858)

..........................You should NOT use gasoline in your diesel, MB put out a TSB on this issue = use kerosene.

Gasoline does nothing to algae/fungus.

A small percentage of gasoline:
* May break up diesel sludge.
* Lower the jell point of diesel fuel.
* Lower the diesel fuel combustion/ignition point = easier to start cold.
* Reduce your MPG.
* Reduce the lubricity of ULSD = greater internal wear on the injection pump.

Ethanol-diesel fuel blends, cause cavitation, resulting in injection pump and injector damage.

Originally Posted by paddo (Post 2637030)

FYI:


It has been a few more weeks and there is no longer any indication of filter blockage, suggesting the growth has gone from my tank.

The reason Mercedes once recommended to add gasoline in winter if necessary, was for better starting. The reason for changing that recommendation was the risk of explosion. Pure gasoline's partial pressure creates a gas/air mixture that is too high in gasoline to be explosive. A certain range of ratios of gasoline will create an explosive level of gas:air, but I don't know what that ratio range is. It's a good point that a lot of modern gasoline has ethanol and I hadn't heard of ethanol damaging injectors before. I'm not sure if ethanol is added in PA / Jersey.

As far as the tank growth goes, it seems clear that it is not a problem for gasoline fueled vehicles. Clearly the growth can't feed on pure gasoline. The question is what minimum ratio of gas:diesel is required to kill the growth. My recent experience seems to suggest that the amount I added was very effective but I'd like to see a few more experiments with this. OF course if you have information that refutes this, I'd be interested to see hear back.

It does seem that due to the possible ethanol issue, it would be better to avoid adding gas all winter, and is unnecessary anyway. However I don't believe that a tank of 10% gasoline no more than every 2 or 3 years (when there is water accumulation leading to growth) will cause significant reduction of injector life. It may be that kerosene is similarly microcidal although I doubt it since it is much more similar to diesel fuel and a lot more pure. But if it is, that would be the perfect solution. I saw Kero the other day for sale, cheaper than diesel! Next time if ever, I have a grawth problem, I'll try a kerosene treatment. There may be forum members who run kerosene mix here, who can report on whether they have ever had a growth problem.

The other dilemma is whether to add any of the expensive tank cleaner I bought to emulsify the water. A previous poster advised that this emulsified water is just as harmful to the fuel system as unemulsified. Possibly it separates out quickly as it is heated on the way to the injectors, which would be harmful of course. so I'm not sure what to do, I think I'll just keep driving for now since the problem seems to have been solved.