Asphaltene

[Rawze]

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Quote:Asphaltene is a black, gritty substance that gets in your tanks, plugging up fuel filters and injectors. Fleetguard makes a product called 'Asphaltene Conditioner' that is pretty good at reversing asphaltene buildup problems if you get them. Many mechanics mistake this as 'soot', or oil intrusion, but it is actually a by-product of bio-diesel after it has started to separate under extreme pressures. This is actually a common problem with Cummins engines because the fuel compression is so high in the injectors, so it is a good idea to keep a close eye out for it if you own an ISX. Using an external filter/water seperator, such as a Davco, with a 10-micron or smaller filter in it will keep asphaltene at bay quite well on its own as well. Asphaltene can be treated by using 10 or smaller micron filters along with this product: Asphaltene Conditioner

It has to do with the amount of bio-diesel you are putting in your tanks. It is not specifically an "engine problem", but a supply problem that gets out of hand if you don't use good fuel filtration to keep it at bay.\

Like others have said. Just use 10-micron (or 7 micron if you are really paranoid about it) fuel filters in your fuel-water separator and it will keep it at bay.