The 8008 1788

It is a common problem on all diesel that is stored for prolonged times, especially if there is condensation in the tanks. I have run into it frequently both in administration of backup diesels for IT&Telecom and for sailing&commercial vessels fueling from sources outside the well-trod path.

Symptomes start with lots of black smoke from the engine, and small runs where the engine refuses to give proper effect for 10-30 seconds. Starting can get interesting. It gets worse with agitation of the tank. Then your filters start to clog, and the engine stops when you draw the tank down to a third and you generally have a misrable time.

You can clean it out, involving emptying the whole tank and supply chain, washing it, and adding anti-microbe stuff to the diesel. It usually only helps for some months to a year; if you got these microbes from somewhere they will reappear when you fill there again.

If you run the engine with good regularity and always draw the tank down to near empty they never get to develop to a really bad situation, but remain a nuisance. I suspect this is the case for lots and lots of black smoke emitted.

The better solution is a stronger pump plus a separator in the fuel line. The better separators can manage 40% water, 20% microbe gel and 40% diesel, and send only the diesel on. It does solve the problem, but at a cost of ~$600 plus install, and it is somewhat bulky, needs around 2 ft^3 in the motor area. It also needs to be drained to somewhere.

This is a prime example of evolution in action. During the last century a new habitat has developed, and microbes have adapted. They actually live on the diesel.

-- mrr