Cummins ISB 350 Fuel Filter & water sep Filters changes

[N6CUS]

Been thinkin on changing my fuel filters, I've had it done 2 times already
first time by A Fleetwood Service and they had a very hard time getting the Cummins ISB started again. then when it did it ran rough, very rough
then at my 12,000 mile M2 Service I had it done again, this time no problems starting or running. I talked to them about how they did it
and was told they filled the fuel filter with fuel then installed it.
I asked Cummins that question and they said don't do it that way cause
fuel is not filtered, and I don't know if theu ever changed the water seperator filter inside the see thru bowl.

My questions is
1, does fuel from the tank go thur water seperator first of fuel filter first
before going to the engine?

2. How do "I" change the filters and in what order?
(don't want a situation where I have to tow it in to get system recharged or bleed)

3. suggestions to look out for?

I want to do this before my up coming 5,000 trip

Any help or suggestion would be greatly appreicatied

Ron

[Ray,IN]

Pre-filling the new filter with fresh fuel prevents air-lock/hard starting. Usually there is a priming pump on top of the filter housing, and a bleed screw to allow the air to escape as you pump fuel into the filter. The procedure is in your Cummins engine book, which is separate from the general owners manual.
If my memory still works correctly, filling the filter through the outside holes (where the unfiltered fuel enters) filters the fuel when it flows into the center.

[N6CUS]

All done and thanks for the help.
as it all turned out I decieded to go to Frieghliner and have it done
with the simpulation THey would instructed me along the way.
Reason
I started the morning myself with filling the water seperator with fuel and using the filter my book said, I got my wrenches, oil for o ring filter full of diesel a little screwdrive to undo the wire connector harness, I notice that it is a screen in connector not a slip on like the new filter, PROBLEM seems cummins ship the engine with one kind of filter and Frieghtliner changed to another. I'm pissed as I now have a new filter full on fuel and its no good to me at all $40 down the drain.
I gave up and went to freightliner with what I wanted ( instruction)
a chassis lube (18 points) and differentail checked.
they showed step by step how to do it and wasn't very neat about filling the filters full, I thought no air bubbles and entirely full
Nope 7/8 full and slap it on fuel filter and he said start it up.
it cranked about 3 times normal lenght maybe 4 to 5 seconds and it started and ran smooth. Next water seperator same thing clean clean bowl on bottom, oil o ring put 2 parts together fill it 7/8 or so full
and put it back on and plug in wire harness. cranks 4 to 5 seconds and ran smooth, drove home all is smooth and cost $160 for everything including all fitlers
I was always afraid to do this as the frist time I had it done at a Freightliner Oasis dealer they cranked and cranked many times and finally after 30 min of so it started and ran so rough and they tell me some BS about new engines now having elec lift pumps and that all was it was BS
acutally this is so simple I'd say less problems than changing the oil
for all those that gave me thier advice I thank you. I made domwthing out of nothing as I finally found out.
Ron K