I say phhht on single tank systems. In my opion, its just too risky. I don't relish the thought of ruining my ip so I'm as picky as possible with my oil and making sure its warm enough. I have a copper heat exchanger in the tank, glow plug heater before the filter, and a VegTherm heater right before the ip. Not taking shots at all you blenders, I just wouldn't use a single tank system unless it was an Elsbett.

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Seth

1984 300D 225K
1985 300D Donor body
1985 300D Turbo 165K. Totaled. Donor Engine. It runs!!!
1980 300SD 311K My New Baby.
1979 BMW 633csi 62K+++? Dead odo