the stock Webasto air top at-2000 fuel pump (12 volt) does not work in an Eberspacher (espar) D1LC. we measured the volume of fuel output using a procedure detailed on page 23 of the Espar installation troobleshooting & parts manual, by letting the pump expel fuel into a cup (shot glass) for 90 seconds. not having a proper measuring cup, we weighed the output on a suitable, sensitive scale for results.
output was 13.6 grams of diesel. average density of diesel listed at 0.85 kg/l, so that's 16 milliliters of fuel.
the espar manual states the fuel delivered in this startup cycle should be between 3.4ml and 4.65ml. so, much less. it was also clear after operating for a few minutes, that excess fuel was not being burned off and the unit was spewing smoke like mad.
so the pump output is too strong, waaay too much fuel. so i'm still looking for a proper esbar fuel pump (mfg. part: 25 1830 45 00 00), any tips?
on a curious note, the heater contains fairly advanced microprocessor, electronics, and sensors. they are reasonably well built and remarkably intelligent. i had not realized the level of sophistication these 'simple' heaters enjoy, it's pretty amazing. now, only if it worked. sigh.