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Topic: change fuel filter/water separator,leaking from drain. (Read 2429 times) previous topic - next topic

change fuel filter/water separator,leaking from drain.

How stop fuel while filter unscrewed?

thnx,

Jim
'92 Grand Villa 36' w/8.3Cummins mechanical
ORED
Build#4062

Re: change fuel filter/water separator,leaking from drain.

Reply #1
Jim,

I'm not sure I'm understanding your question.  Are you asking if fuel will run out of the filter base while you are changing the filters?  In my limited experience, there is very little drainage from the lines while the filters are removed.  I was expecting it to be a problem the first time I changed mine, but it just didn't happen.  If anything, I think the fuel tends to siphon backwards toward the fuel tank, drawing some air into the lines.  That is why the engine runs a little rough when you first start it with fresh filters.

I warmed my engine up to operating temp before changing filters, and pre-filled my filters with fresh diesel prior to installing.  I had no difficulty restarting the engine after swapping both filters.

You do have a manual priming pump that is part of the transfer pump (lift pump).  See photo below of old and new pump.  The priming pump is the "button" on the bottom of the lift pump.  It is protected with a black rubber cover.  This primer can be used if you have a hard time getting the engine to start, but I did not find it necessary to use it on our coach. 
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: change fuel filter/water separator,leaking from drain.

Reply #2
The diesel engines have what's called a "high side" and a "low side". If you're changing filters, they're on the "low side" and need nothing to start. However, if you run the coach out of fuel (a no-no), you're on the "high side", and you'll need the pump to get it flushed of air. If that happens, be very carefull to shut the bleeder all the way down.  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: change fuel filter/water separator,leaking from drain.

Reply #3
Mike,

Both your coach as well as the vast majority of Foretravels have two fuel filters:  Primary fuel filter/water separator between fuel tank and lift pump.  The secondary filter is on the pressure side of the lift pump.

Bleed procedure varies by engine family.  Some have an electric pump.  Some (like your Cat 3116) have a manual primer pump.  So no "one way fits all".
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: change fuel filter/water separator,leaking from drain.

Reply #4
Mike,

  Some (like your Cat 3116) have a manual primer pump.  So no "one way fits all".

Thanks Bret - my manual says it is a 8.3 250hp Cummins. Where do I find a tag to verify same? It's an inline six.

Jim
'92 Grand Villa 36' w/8.3Cummins mechanical
ORED
Build#4062

Re: change fuel filter/water separator,leaking from drain.

Reply #5
Jim,

Brett's comment was directed at Mike Leary (who has a Cat), not at you.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: change fuel filter/water separator,leaking from drain.

Reply #6
Thanks Brett - my manual says it is a 8.3 250hp Cummins. Where do I find a tag to verify same? It's an inline six.

Jim


Yes, Jim, you have a Cummins "C"-- a very good engine.

 It is a linered engine, so be sure coolant is correct (either low silicate with added SCA that you check and keep the SCA concentration where it needs to be OR one of the newer long life coolants that do not require SCA testing and addition).
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: change fuel filter/water separator,leaking from drain.

Reply #7
Quote from: Chuck & Jeannie link=msg=227441 date=145 Brett's comment was directed at Mike Leary (who has a Cat), not at you. [/quote
Yup, and sorry for the confusion on my part: both my Isuzu engines had bleeders and I assumed (wrongly) all the big diesels had them, as well. Is it a pain to bleed the other engines if one (gasp) runs out of fuel?
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: change fuel filter/water separator,leaking from drain.

Reply #8
Mike,

That's OK...confusion is normal around here.

Bleeding.  It has never come up for me (knock on wood), but on the (mechanical) Cummins engines I think all you do is loosen the fuel line connections on top of the injectors, and pump the priming pump.  When fuel dribbles out at the connection, tighten it back up and you're good to go.

I don't plan on EVER running out of fuel!  8)
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: change fuel filter/water separator,leaking from drain.

Reply #9
Actually, "best practices" is to always run on the top half of the tank.  Fuel is used to lube and COOL fuel injection components and parts of the head on some engines.  For every gallon of fuel that goes to the engine, most return to the tank.

Operating on the top half insures better cooling of engine components/cooler fuel temperatures.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: change fuel filter/water separator,leaking from drain.

Reply #10
Thanks for the schooling session folks - and especially Bret as I was wondering about cylinder linings...

Jim
'92 Grand Villa 36' w/8.3Cummins mechanical
ORED
Build#4062

Re: change fuel filter/water separator,leaking from drain.

Reply #11
Bleeding.  It has never come up for me (knock on wood), but on the (mechanical) Cummins engines I think all you do is loosen the fuel line connections on top of the injectors, and pump the priming pump.  When fuel dribbles out at the connection, tighten it back up and you're good to go.
I suggest you NOT make any changes to the fuel lines on top of the injector pump. One of the mechanics at FOT loosened and tightened one of the injector lines to bleed air after they replaced fuel lines. I had a fuel leak at that point for a year. Folk at FOT could not find the source of the leak. I took the coach to someone who knows Cummins engines. He quickly identified the problem. He did some machining on the injector line and tightened it to the proper torque. It has not leaked since then.

I trust FOT to do a lot of service on my coach. However, I take the coach elsewhere if there is an engine issue that requires any more service than changing fluids.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: change fuel filter/water separator,leaking from drain.

Reply #12
I try to avoid changing filters with a full fuel tank, just in case.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: change fuel filter/water separator,leaking from drain.

Reply #13
With my 96 U320, to drain water from water/fuel separator, tank must be almost full or rear must be much lower than front. With less than 3/4 tank, air sucks into water/fuel separator, so there would be no fuel leaking when changing fuel filter. Air in fuel line is easily removed using suction on the schrader valve. I have a hose with female connector from a hand air pump that I use to do this.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: change fuel filter/water separator,leaking from drain.

Reply #14
Amen for keeping your fuel level @ 1/2 tank plus.
Especially if you are the owner of anything with a small cell (ie; auto, pickup, etc..)
2 stroke additive and cetane booster hurt nothing.
FWIW.. Current fuel reg's and older diesels are not a positive combination.. pc
S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..

Primary filter/water separator

Reply #15
I'm having a heck of a time finding one - the AC number on Beamalarm will will not cross over to anything in my neck of the woods. The water drain valve on mine is leaking. Anyone have a good number of a filter that will replace mine? The one on there now has a transparent sediment bowl with the bleeder on the bottom of that - don't know if that was OEM or not....How do I keep from getting soaked when I take that filter off(as we did when we  replaced the fuel line!

Jim
'92 Grand Villa 36' w/8.3Cummins mechanical
ORED
Build#4062

Re: Primary filter/water separator

Reply #16

For what it is worth--on my '89 DD 8.2--- I position a drain pan or pail under the primary filter. Then I test that I am going to be able to unscrew the filter. I do this, just in case I can't get it off easily. Then, having confirmed that I will be able to unscrew the filter I use a long bladed screwdriver and punch a hole in the bottom of the filter. I wait until fluid quits draining and then I unscrew the filter.
I prefill the new filter, grease the threads and the rubber seal, and then screw the filter on. I then start the engine and let it run for a few minutes to get any air out of the line.
I then proceed to do the secondary filter the same way.
Amazing how clean I stay compared to the old way of just unscrewing a full filter and getting diesel fuel all over everything!!
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Primary filter/water separator

Reply #17
What drenched us was fuel from the tank - running free flow until we raised the line 'til it stopped. Will fuel gush from the filter mtg as it does from the hose?

Jim

'92 Grand Villa 36' w/8.3Cummins mechanical
ORED
Build#4062

Re: Primary filter/water separator

Reply #18
Most likely will keep running unless you put a clamp on the rubber line. Don't know if that would be a good idea, tho, unless lines are fairly new and pliable.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Primary filter/water separator

Reply #19
I can be a Racor S3202 or a Fleetguard FS 19520, do yourself a favor and buy a second clear bowl, that way you can have a fitler that is prefilled and ready to swap out.
The selected media item is not currently available.Bill&Doris 97 U270 36'
University of Parris Island Class of 66
Semper Fi  Build# 5174 MC#17094

Re: Primary filter/water separator

Reply #20
I try to make sure the tank is about 1/2 full and then raise the rear and lower the front of the coach.  Seems to help a lot.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Primary filter/water separator

Reply #21
I installed a new Racor 1000FH turbine filter/water separator. IMO it would be less likely to plug up in the event of a bad tank of fuel.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: change fuel filter/water separator,leaking from drain.

Reply #22
I can be a Racor S3202 or a Fleetguard FS 19520, do yourself a favor and buy a second clear bowl, that way you can have a fitler that is prefilled and ready to swap out.
Bill, will you elaborate - I don't understand about the second bowl?
Do the sediment bowls come with the new filter? How about the petcock?

Jim
'92 Grand Villa 36' w/8.3Cummins mechanical
ORED
Build#4062

Re: change fuel filter/water separator,leaking from drain.

Reply #23
Jim,

Bowls do not generally come with the filters.  I agree-- easier and safer (in case a plastic bowl breaks) to have a spare bowl.  Install it on the new filter element at your leisure.  Makes changing filters less of a "drama".
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: change fuel filter/water separator,leaking from drain.

Reply #24
Jim,
Fuel will continue to run out the hose when the filter is removed.  Try to find a large drain pan, and if you purchase another bowl you can assemble the new filter and have it filled with fuel so that when you drop the old filter you can immediately install the new, thus cutting down on the amount of lost fuel.
It is also good to have the second bowl so you can carry a spare filter already assembled in case you ever get bad fuel.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.