anahata
Veteran Member
HB,
There are many places to research 'occasional' use of B-100 here and much has been written. I am far from a guru but am an avid reader of the forums. My understanding is that good B-100 is a great fuel but seals on (edit) injector pumps on cars old enough to have run on regular LSD are prone to failure when switching between fuels - because the different fuels contain different aromatics and/or aniline which variously swell or shrink the seals stressing them when fuels are substantially changed.
I haven't seen a decisive conclusion as to whether or not it is 'safe' to go from one extreme to another with IP seals that have only seen ULSD and Biodiesel. My seals ran all three fuels and eventually leaked. So, it will not harm the engine but the IP seals could be another story.
http://forums.tdiclub.com/search.php?searchid=4320890
http://forums.tdiclub.com/showthread.php?t=157540
I would pick a blend and stick with that blend myself even after having new seals put on the pump and only running ULSD. It is said that IP's with seals that have only pumped ULSD are less vulnerable but I don't want to take that chance. I too am interested in any further light on this though I don't want to divert this thread.
Back to topic...FWIW I live in Arizona and have been splash blending to equivalent of B-5 for 4 years (it's cheaper! AZ petro sells B5, B20 & B99 but am not sure how they blend it) I too was under the impression that Biodiesel is MORE dense and not less dense than Dino. This would be a major decider in which fuel to add first if one is splash blending. Any conclusive answers about the relative density question?
There are many places to research 'occasional' use of B-100 here and much has been written. I am far from a guru but am an avid reader of the forums. My understanding is that good B-100 is a great fuel but seals on (edit) injector pumps on cars old enough to have run on regular LSD are prone to failure when switching between fuels - because the different fuels contain different aromatics and/or aniline which variously swell or shrink the seals stressing them when fuels are substantially changed.
I haven't seen a decisive conclusion as to whether or not it is 'safe' to go from one extreme to another with IP seals that have only seen ULSD and Biodiesel. My seals ran all three fuels and eventually leaked. So, it will not harm the engine but the IP seals could be another story.
http://forums.tdiclub.com/search.php?searchid=4320890
http://forums.tdiclub.com/showthread.php?t=157540
I would pick a blend and stick with that blend myself even after having new seals put on the pump and only running ULSD. It is said that IP's with seals that have only pumped ULSD are less vulnerable but I don't want to take that chance. I too am interested in any further light on this though I don't want to divert this thread.
Back to topic...FWIW I live in Arizona and have been splash blending to equivalent of B-5 for 4 years (it's cheaper! AZ petro sells B5, B20 & B99 but am not sure how they blend it) I too was under the impression that Biodiesel is MORE dense and not less dense than Dino. This would be a major decider in which fuel to add first if one is splash blending. Any conclusive answers about the relative density question?
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