Davco filter Replacement
They skip over it pretty quick but an important part is when fitting the clear fuel bowl apply down pressure you will be able to see the o-ring seated correctly. Continue the downward pressure and fit the collar. Tighten the collar. Dont let the Fuel bowl spin, it should not move because it risks the o-ring coming out of place.
Note- I dont recomend re-using the fuel you drained from the bottom of the fuel bowl.
for more information go to
Written Filter Change Procedure
Remove the vent cap and open the drain valve to drain
the fuel below the collar level.
Remove the collar (using a DAVCO wrench) then remove
the clear cover.
Remove the filter, cover and vent cap seals. Dispose of
Using a clean shop rag, clean the cover, the collar and
threads on the Fuel Pro body.
Install a new filter, cover seal and vent cap seal.
To tighten the collar with the wrench, simultaneously ap-
ply downward pressure to the top of the clear cover until
it is seated on the body of the Fuel Pro and hand tighten
the collar until it no longer spins freely. Torque the cover
assembly by rotating the collar clockwise two additional
ribs using the collar wrench (~18 ft-lbs).
Prime the unit by filling the clear cover with clean diesel
fuel until it reaches the top of the filter.
Install the vent cap and hand tighten until it clicks
the engine and run for one minute.
open the vent
cap and allow the fuel to drop to about one inch above
Close the vent cap. Tighten the vent cap by hand until it
clicks. It is normal for the fuel level to vary after the initial
start-up and during engine operation. Filter performance
is not affected.