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Topic: M11 Fuel Filter Replacement Process (Read 3348 times) previous topic - next topic

M11 Fuel Filter Replacement Process

I am gearing up to replace both fuel filters on my M11. I'm looking at my shop manual and the process for replacing the primary filter looks straight forward and perhaps even easier than on my Power Stroke. However, I can't find mention of the secondary filter anywhere in the manual. Does it go by a different name? My search results here on the forum seem to indicate it's called the "Winn" filter but I don't see anything in the manual for that either.

Is the process for both filters to simply do as follows?
    • Twist off old one
    • Clean mounting surface
    • Prime new filter with fresh diesel
    • Lube gasket
    • Twist back on
    [/list]

    I also can't find a part number for either filter in the manual. Search results here yield loads of different part numbers but none of those posts are recent. If I didn't have you guys to lean on, how would I go about finding the right fuel filters? It seems to me I'm missing something.

    Edit: I should add that my shop manual appears to have been printed in November of 1994... perhaps it's too old?


    1987 Grand Villa ORED
    2001 U320 4010

    Not all that wander are lost... but I often am.

    Re: M11 Fuel Filter Replacement Process

    Reply #1
    The Winn is the primary filter if yours is original. The secondary filter is mounted on the passenger side of the engine and looks like a regular spin on filter.
    1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
    prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
    2014 Grand Cherokee Overland
    Dream as if you will live forever. Live as if you will die today.  James Dean

    Re: M11 Fuel Filter Replacement Process

    Reply #2

    My secondary filter has a valve on the bottom to drain fuel.  Put a plastic bag over the filter while removing it to reduce mess.

    If your Your primary filter has been updated it will have a bottom part that screws on the bottom and the whole thing screws to the fitting on the top. If you have the prescreen filter loosen the thumb screw at the top and tempve the fuel lines from the top. A small bucket will catch any overflow. The  hose can be tied up high to prevent any dribbles.  The plastic screen filter can be washed with soap and water, rinsed well, and a final rinse with alcohol to get rid of water.

    Reassemble being careful with the orings, lube with a bit of diesel or plumbers grease.  Follow the air purge process, start and run on high idle for three minutes.

    Shop around for price and delivery time, get at least two spares of each.

    Racor S3230P Fuel Filter Water Separator
    Amazon.com: Racor S3230P Fuel Filter Water Separator: Automotive

    Secondry Fleetguard FS1001

    This one should work Amazon.com: iFJF FS1001 Fuel Filter and Water Separator Combo for HD...

    FLEETGUARD FS1001 replacement fuel filters
    ALLIANCE ABPN10GFS1001
    BALDWIN BF1258
    BIG-A 95407
    CARQUEST 86407
    CASE-IH 335341A1
    CUMMINS 3413084
    DAEWOO 65125035016
    DONALDSON P551001
    FIL ZP512DF
    Fram PS8047
    HASTINGS FF1147
    KRALINATOR FS345
    LUBER-FINER LFF1001
    MANN WK10012X
    NAPA 3407
    WIX 33407
    WIX 533407






    Re: M11 Fuel Filter Replacement Process

    Reply #3
    If you don't have clean diesel then use a new container of ATF fluid to fill the filter.
    Forest & Cindy Olivier
    1987 log cabin
    2011 Roadtrek C210P
    no longer 1999 36' U320 build #5522
    2013 Rzr 570 & 2018 Ranger XP1000
    2006 Lexus GX470
    2011 Tahoe LT 4x4
    Previous 1998 45' 2 slide Newell, 1993 39' Newell

    Re: M11 Fuel Filter Replacement Process

    Reply #4
    I have Baldwin brand filters on my M11:
    Primary - BF781
    Secondary - BF1258
    John & Genni Kerbs
    ex 1993 U280 40'
    1997 U320 40"
    Build #5171
    Engine: M11 450
    Floor plan: walk thru bath

    Re: M11 Fuel Filter Replacement Process

    Reply #5
    If you have Winn pre filter get spare o rings. There are 2  on filter and 2 more in housing. Mine was sucking air. New o rings fixed it
    2001 4010 U320
    Build 5875

    Re: M11 Fuel Filter Replacement Process

    Reply #6
    Thanks guys great stuff.

    Follow the air purge process, start and run on high idle for three minutes.

    Roger, is the "air purge process" the same as is listed under the "Operation" section of the document you shared?

    1987 Grand Villa ORED
    2001 U320 4010

    Not all that wander are lost... but I often am.

    Re: M11 Fuel Filter Replacement Process

    Reply #7
    Yup.  Ignition needs to be on. With new filters I usually run it two or three times. It is also a way to make sure your engine has fuel at the engine before you start it.  If your coach has sat without running for a few months give it a try. 

    Re: M11 Fuel Filter Replacement Process

    Reply #8
    No need to fill filters. Depress air vent and vent air out with air purge button. Filter on engine will fill and return air back to tank. Common rail engine. The four o-rings on the clear screen do fail. Replace and keep spares. I like DC4 on the filter seals, makes removal much better. I destroyed a filter wrench on the engine mounted filter prying it off. I like to carry spares for all.
    Scott
    Scott and Kim Davidson
    If you're going to be dumb, you got to be tough.
    DEGOIWKY
    Don't ever get old, it will kill you
    June 30, 2020
    2001 U320 3610 Barn find
    Build 5834

    Re: M11 Fuel Filter Replacement Process

    Reply #9
    These are the oring sizes needed for the pre-filter.
    I would have preferred both in 70, but the only 90 was available for the one size at the time I ordered.
    40ft 1997 U320

    Re: M11 Fuel Filter Replacement Process

    Reply #10
    Just a note on filter replacement process-make sure you remove old filter seals, which may still be stuck in place once the filter is removed.  Not doing so will cause double gasketing and a guaranteed fuel leak.
    Regards,
    Brett

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

    Re: M11 Fuel Filter Replacement Process

    Reply #11
    My secondary filter has a valve on the bottom to drain fuel.  Put a plastic bag over the filter while removing it to reduce mess.

    If your Your primary filter has been updated it will have a bottom part that screws on the bottom and the whole thing screws to the fitting on the top. If you have the prescreen filter loosen the thumb screw at the top and tempve the fuel lines from the top. A small bucket will catch any overflow. The  hose can be tied up high to prevent any dribbles.  The plastic screen filter can be washed with soap and water, rinsed well, and a final rinse with alcohol to get rid of water.
    Thanks Roger, I think I have the same setup as you suggest here. Could you help me clarify the process of removing everything? The attached pic is how I'm planning on attacking this and I'd just like a bit of confirmation. I have some confusion about how to get at the pre-screen filter on the right.

    Also, if someone could just give me an overall explanation of how these components work I'd really appreciate it. I assume fuel enters from the right, through the clear pre-screen filter, and then goes through the primary filter and then back out the big line on the left. If so, what's the little line coming out of the bottom of the primary filter?

    Thanks... feels like I'm asking silly questions about something simple but you don't know until you know.

    EDIT: if anyone has a link handy to their favorite filter wrench I'd appreciate it. I'll double check later this week but I'm pretty sure the one I have for my Powerstroke won't be big enough and getting a pair of channel locks on their looks tricky
    1987 Grand Villa ORED
    2001 U320 4010

    Not all that wander are lost... but I often am.

    Re: M11 Fuel Filter Replacement Process

    Reply #12
    The clear filter with the screen in it I leave alone if it is clean although it looks from the picture you might have some dirt in it.
    It's been awhile since I have had the clear one apart but I remember it being a little tricky. Someone will come up with the answer.
    The rest is like you have drawn. Take the line off the bottom and twist the bottom off and then twist the filter off. I use a strap
    wrench for all my filters. If you are changing the oil fill the oil filter up before installing it. 
    Peter and Frieda Morin
    1999 36ft. U320 Foretravel
    Build # 5436
    1998 Suzuki Sidekick Sport

    Re: M11 Fuel Filter Replacement Process

    Reply #13
    Might consider upgrading the old Winn to a Racor 700 Series.
    Charles
    W5CRY
    1997 Dynasty - Sold

    Re: M11 Fuel Filter Replacement Process

    Reply #14
    For the clear one, loosen the thumb/wing screw you marked and the whole top assembly will lift off, then you can remove the plastic bowl.  Consider replacing the o-rings that are on the plastic bowl top and bottom and inside the metal housing top and bottom.
    40ft 1997 U320

    Re: M11 Fuel Filter Replacement Process

    Reply #15

    quote author=DayDreamer link=msg=410393 date=1606996696]
    It is easy to miss the o-rings inside the upper and lower housing unless you know they are there. Even if you purchase a new pre-filter, it does not come with the smaller ones needed for the housing.

    These are the ones I ordered.  The ones on the right (114) go inside the housing.  The ones on the left (208) go over the pre-filter.

    I ordered from Amazon....but forgot to use the affiliate link  :(

    208 Buna-N O-Ring, 90A Durometer, Round, Black, 5/8" ID, 7/8" OD, 1/8" Width (Pack of 50): O Ring Seals: Amazon.com: Industrial & Scientific

    114 Buna-N O-Ring, 70A Durometer, Black, 5/8" ID, 13/16" OD, 3/32" Width (Pack of 100): O Ring Seals: Amazon.com: Industrial & Scientific


    [/quote]
    Orings plastic screen is a racor 300200 Racor 200 Micron Pre-Filter with O-Rings 300200 | M&D
    Scott

    Scott and Kim Davidson
    If you're going to be dumb, you got to be tough.
    DEGOIWKY
    Don't ever get old, it will kill you
    June 30, 2020
    2001 U320 3610 Barn find
    Build 5834

    Re: M11 Fuel Filter Replacement Process

    Reply #16
    Quick question for those of you that carry spare filters with you. What's your plan for priming the filters if you need to change one on the side of the road? Siphon diesel out of the tank?
    1987 Grand Villa ORED
    2001 U320 4010

    Not all that wander are lost... but I often am.

    Re: M11 Fuel Filter Replacement Process

    Reply #17
    Quick question for those of you that carry spare filters with you. What's your plan for priming the filters if you need to change one on the side of the road? Siphon diesel out of the tank?
    Your coach had a water and air bleed function. Just use the air bleed until it quits pumping and it will fire up, mine does.
    1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
    prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
    2014 Grand Cherokee Overland
    Dream as if you will live forever. Live as if you will die today.  James Dean

    Re: M11 Fuel Filter Replacement Process

    Reply #18
    As Chuck said, use the air bleed, maybe two or three times. Start the engine and set idle to middle high (cc On, press set) about 800 rpms for 3 min.  Check for leaks.

    Re: M11 Fuel Filter Replacement Process

    Reply #19
    Thanks guys, I'll test it out when I change this set of filters.

    When would one use the H20 purge?
    1987 Grand Villa ORED
    2001 U320 4010

    Not all that wander are lost... but I often am.

    Re: M11 Fuel Filter Replacement Process

    Reply #20
    You should see an H2O indicator light and an H2O Purge button.  The light comes on if it senses water, push the button to purge water.  I don't think I have ever done this or needed to do it. 

    The air purge can also be like a primer.  If your coach sits without running for a few months, run the air purge a couple cycles before starting.

    Re: M11 Fuel Filter Replacement Process

    Reply #21

    No need to fill filters. Depress air vent and vent air out with air purge button. Filter on engine will fill and return air back to tank. Common rail engine.
    Scott
    [/quote]
    Scott, I take it that this is for the Winn filter. Previous owner installed Racor 700 ( thank you very much ), and Keith at MOT told me I did NOT have top refill my filters, as I have a prime button. Doesn't all 2001 U320 FT have the prime button?
    Glenn and Amy Beinfest
    2001 36' U320
    #5812
    2014 Honda CRV

    No Whining on the YACHT

    Re: M11 Fuel Filter Replacement Process

    Reply #22
    Air purge button is what Keith at MOT was likely referring to.  Turn on the ignition (don't start the engine) press the air purge button.  A small pump moves fuel and gets rid of air.  There is a Schrader valve under a cap to get rid of excess air quickly but fuel (under pressure) will come out if you hold it too long.

    See the Operation section in the Racor manual, post #2.



    Re: M11 Fuel Filter Replacement Process

    Reply #23
    Changing filters on my rig and have the same setup as Elliott.  Does anyone have the part number for the aluminum housing on the bottom of the FS19592 filter in his picture?  My looks a bit crusty and if it's anything like the other filter bowls from my AH and generator, I'd rather just replace now.
    Keith
    2003 U320 38' #6197