02-06-2018, 02:16 AM
(02-06-2018, 01:56 AM)SportsterDoc_imp Wrote:(02-06-2018, 01:42 AM)SpamJ_imp Wrote: Most Vehicles use the Fuel in Fuel tank to cool the Fuel pump, so running it our "might" lessen the Fuel Pumps life span.
Just a thought
That has been my thinking for many years, however it depends upon the pump system:
A. If continuous flow with unused fuel recirculated to the tank, then flow cools pump.
B. If regulated, such as variable voltage or a pressure regulator and flow is not continuous, then the pump may get hotter.
When I managed an electric motor repair shop, we also sold and repaired pumps and most would burn the seals if run without fluid.
OTOH, the 12 VDC water pumps at our ranch are supposed to be able to run dry without harm. They sure don't like it if not purged before freezing weather!
If there is no fluid then there is no load, so it may overrev --> burnt seals.
Also, if there is no load, current through the pump will be much higher unless the electronics can avoid it. This could also harm the pump.
In any case: I think any modern fuel pump can be run dry for a while without being damaged at all. ("Modern" as "designed after the 80s").