Bad for injectors? How can an 'additive' that improves lubricity can be bad for injectors?
Depends on the injector. In older systems, all of the fuel for a combustion cycle was injected at one time. Today’s modern systems allow several injections during a single combustion cycle. This allows engine calibrations to determine not only how much fuel is injected at each point in the cycle, but precisely when it is injected. The new systems rely on tighter tolerances, smaller injector orifices and higher pressures to produce smaller droplets.
The obvious benefits of biodiesel is increased cetane and added lubricity, but with those benefits comes increased deposits in the injectors of modern systems.
Some batches of biodiesel seems to be fine, some batches not so much. Europe produces about 5 times more biodiesel than we do, and they have a large problem with some batches of biodiesel causing injector problems, but for the most part it's not that big a deal over there, but that's also in large part because all of their diesel is 50 cetane (same as CARB diesel, and the same fuel the Sprinter engine is designed for) and because most of their diesel contains a detergent additive to keep the injectors clean.
When injectors become dirty, clogged, there is a loss of power. Test after test shows this right here:
I used B70 in my sprinter one tank and no problem other than the french fries smell behind. Other times I used B20, B30, still no problem. I guess I like to go out of the norm a little.
It's not like you'll fill the tank with high percentage biodiesel and bam! your injectors are clogged, but the damage will begin there. When you use B30, B70, then you get into the FAME thing. The "fatty acid methyl ester" (FAME) "biodiesel" fuels can cause significant problems with engine systems. The problems are more pronounced with less-used engines, like seasoning equipment, standby generators, etc. But the problems are just as real for everyday vehicles. The problem is, this fuel degrades quickly, and is accelerated by the presence of impurities in the fuel, oxygen, water and heat (keep in mind that the Sprinter recirculates heated fuel to the tank).
The products of bio-degradation are corrosive, with formic, acetic and organic acids, water and methanol compounds doing a real number on the corroding of fuel injectors, elastomer seal failures, leading to fuel system blockage, causing pump seizures, fuel injector spray hole blockage and increase injection pressures.
The corrosive effects on an engine that's used everyday, won't be as immediate, but the corrosion
will occur nonetheless. Over time, it's a problem.
If you use biodiesel, in any blend, the use of a good detergent is an absolute must, and the higher the blend the more detergent is needed. Howes Power Cleaner is the one I use, because it's good, and because if you add too much it won't cause problems on its own, as is the case with many injector detergents.
