Diesel Heater Fuel Pumps

I asked Owen (tech director of Autoterm) He says all the branded heaters use the slope of around 15-30 degrees except a special Webasto one. The slope ensures no air and is quieter. The horizontal info from a dealer is incorrect as there is a spring return. Important that the hose continues to run uphill to the heater.
Thanks for that. Owen seems pretty well versed on this stuff. I may need a bigger heater (since the original is an Eber D5LC which much physically bigger than the Chinese onese) and may end up with an Autoterm 9D. Look pretty decent kit. (Sorry a slight thread drift there)
 
It is also important to mount the filter vertically. I could not get one to fire up as the filter was nearly horizontal.
Yeah I saw that in the instructions.. Even the Chinese instructions which are more like AI English after being jumbled on a scrabble board, show a clear vertical 90 degrees fuel filter.. I follow that closely.
 
The Eber one has its filter built in so can't have that vertical and the pump offset ?
Good point. My Eberspacher has that tiny little filter in the pump but I'm gonna take a punt that due to it being tiny and part of the inlet of the pump it'll work at virtually any angle as opposed to the generic Chinese ones that are about 50 times the size.
 
But without an explanation as to why this makes no sense to me. Vertically they stand a better chance of keeping fuel in, as any child with a glass of water and some paper will tell you! Vertical will also give more consistent pressure on parts, thus preventing wear on one side which would happen faster.

Anecdotally, if my old pump lasted from 1999 until 2023 in a vertical orientation I'd say wear isn't an issue. Even at Eberspacher prices that's only £6 a year and the generic one would be £1 a year which for a consumable part doesn't seem crazy. It was actually still working when I replaced it, just occasionally needed a tap to get going.


Hi could you clarify the vertical position, possibly by identified the highest part at its point ☝️ northwards like is it the water inlets at top or the bulk body housing the burner coil. Etc. Many thanks I'm just setting up my webasto complete newb. With them but experienced in mechanical knowledge. Just my first set up I'm having issues with a particular squawking noise.
 
Hi could you clarify the vertical position, possibly by identified the highest part at its point ☝ northwards like is it the water inlets at top or the bulk body housing the burner coil. Etc. Many thanks I'm just setting up my webasto complete newb. With them but experienced in mechanical knowledge. Just my first set up I'm having issues with a particular squawking noise.
I asked the question too without response. I believe the connector is on the outlet end so the connector should be pointing upwards
 
We were talking about the fuel pump rather than the heater. Usually the pipes are at the bottom on the heater itself, although no idea whether it makes a difference
 
So is it supposed to be 30 or whatever degrees from the vertical or the horizontal? Any instructions that just say 30° is meaningless.
 
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