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Changing fuel filters

I want to change out the fuel filters on my '98 U295 with mechanical Cummins C8.3. Are those in the first two pics the ones I should be changing? First one is in the street side chassis battery compartment, 2nd is hanging off the street side of the engine under the bed.
Also what is the filter(?) seen in the third pic?
1998 U295 36' No slides
Towing 2018 Jeep Wrangler
Previous rigs:
  1995 26' Fleetwood Flair
  1998 34' Fleetwood Bounder
  1997 40' Bluebird BMC
  1999 24' Winnebago Minnie Class C

Re: Changing fuel filters

Reply #1 –
#1 Primary fuel filter/water separator (course element)
#2 Secondary fuel filter (fine element)
#3 Water filter-- the correct one depends on what coolant you use and if "low silicate for diesel with added SCA" it MUST be tested to determine the correct filter, as the filters can add different amounts of SCA which is consumes by protecting the cylinder liners.  If one of the new generation OAT-based coolants, a filter BLANK is correct. A blank has the same filtration, but no SCA.  I.E. DO NOT AUTOMATICALLY USE THE SAME PN AS IS ON THERE NOW.
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: Changing fuel filters

Reply #2 –
Hi Dan,
Brett is correct on the filters, one thing to remember is fill up the new filters with diesel and you will have to prime the system with the manual pump that is attached to the lift pump which is on the side of the engine. Probably about 10 to 20 pumps on the prime pump.
2002 Custom No Slide U320
98 U295 36'
92 Grand Villa 29' front engine gas-Sold
Motorcade 18100

Re: Changing fuel filters

Reply #3 –
Quote from: windwalker –
Hi Dan,
Brett is correct on the filters, one thing to remember is fill up the new filters with diesel and you will have to prime the system with the manual pump that is attached to the lift pump which is on the side of the engine. Probably about 10 to 20 pumps on the prime pump.

This really depends on the engine.  Said another way, advice for a mechanical C engine should NOT be taken as gospel on a newer electronic engine.  So, yes, you will see advice for both your engine and likely several others. Please follow advice for your engine!

With many of the newer Cummins engines, there is an electric fuel pump that runs for 30 seconds or so when the key is turned on.  Easy to identify-- have someone turn the key to on (not start) while you are by the right rear of the coach-- you will hear the pump run and automatically shut itself off after 30 seconds or so.

If you have this setup, no need to pre-fill, as cycling the key a few times does the priming.

One observation irrespective of what engine/coach you have:  If the level of the filter head is higher than the level of fuel in the tank, fuel will drain all the way back to the tank, leaving you with 25+ feet of AIR to purge.  If level of filter head is lower than the level of fuel in the tank, fuel will continue to run out the filter head until the levels equalize (read that a LOT of gallons).  Short term answer is to have the new filter absolutely ready to go so you can do a very quick replacement.

By far the best long-term solution is to install a diesel compatible ball valve on the inlet side of the primary filter.  Close it when changing filters.  BTW, this also makes a heck of an anti-theft device.
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: Changing fuel filters

Reply #4 –
98 8.3 is the mechanical engine no electric primer on it you have to use the mechanical pump on the side of the engine.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Changing fuel filters

Reply #5 –
On the Monaco I had the 8.3 was a mechanical engine but had Winn primary fuel filter system
so there was an electrical pump. I don't see one on your engine so follow Red Tractor advice.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Changing fuel filters

Reply #6 –
On our mechanical C8.3 the following procedure works very well, and requires zero use of the manual priming pump.

1.  Fill the new filters with fresh clean diesel and have them standing by ready to install.
2.  Start the engine and run it long enough for the idle to smooth out and coolant temp to come up a bit.
3.  Shut off the engine, remove the primary filter, install the new filter.
4.  Start the engine and let it run a few minutes until it idles smoothly.
5.  Shut off the engine, remove the secondary filter AND THE OLD GASKET, then install the new filter with new gasket.
    Note:  I lift the mattress platform, climb into the engine bay, stand on the transmission bell housing, and R&R the secondary filter from above.
6.  Start the engine, check carefully for leaks at both filters.

Works for me, with only minimal fuel loss which is easy to catch with a rag.  Others may have differing experience.

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: Changing fuel filters

Reply #7 –
Quote from: wolfe10 –
#1 Primary fuel filter/water separator (course element)
#2 Secondary fuel filter (fine element)
#3 Water filter-- the correct one depends on what coolant you use and if "low silicate for diesel with added SCA" it MUST be tested to determine the correct filter, as the filters can add different amounts of SCA which is consumes by protecting the cylinder liners.  If one of the new generation OAT-based coolants, a filter BLANK is correct. A blank has the same filtration, but no SCA.  I.E. DO NOT AUTOMATICALLY USE THE SAME PN AS IS ON THERE NOW.

SCA is Supplemental Coolant Additive.  Just sayin'
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Changing fuel filters

Reply #8 –
Quote from: Old Toolmaker –
SCA is Supplemental Coolant Additive.  Just sayin'

Correct!
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: Changing fuel filters

Reply #9 –
For what it is worth, because the bottoms of all my filters are a bit convex, I made a wooden box to hold the filled filters upright until I was ready to install them. Got tired of the spillage on the driveway. The used filters were OK to just let them down into the drain pan.
The whole operation is a lot cleaner, neater, and faster now.
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: Changing fuel filters

Reply #10 –
Okay, just ordered the new filters, 2 of each so I have a spare, and am ready to do this next week when the Amazon delivery truck arrives. Thanks, all.
1998 U295 36' No slides
Towing 2018 Jeep Wrangler
Previous rigs:
  1995 26' Fleetwood Flair
  1998 34' Fleetwood Bounder
  1997 40' Bluebird BMC
  1999 24' Winnebago Minnie Class C

Re: Changing fuel filters

Reply #11 –
Quote from: Dan & Annie –
Okay, just ordered the new filters, 2 of each so I have a spare, and am ready to do this next week when the Amazon delivery truck arrives. Thanks, all.

Do you have the wrenches you need to install them?
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Changing fuel filters

Reply #12 –
Big channel locks work fine for me.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Changing fuel filters

Reply #13 –
Quote from: John44 –
Big channel locks work fine for me.

I find that a rubber strap wrench such as carried by Lowes, Harbor Freight and others works best for me. A set of two different sizes is available at low cost.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Changing fuel filters

Reply #14 –
If your rubber primer bulb is on the lift pump like my mechanical 8.3 the easiest way to pump it is raise the bed and take a claw hammer by the head and use the end of the handle to pump the primer pump. Makes quick work and an easy reach, if it's like mine.
Dub McBride 1996 270

Re: Changing fuel filters

Reply #15 –

This is the one I carry. Works great on seized toilet flanges too.

RIDGID 42478 STRAPLOCK Pipe... Ridgid 42478 Straplock Pipe Handle 7" Strap Wrench, Red - - Amazon.com

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1987 Grand Villa ORED
2001 U320 4010

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

Re: Changing fuel filters

Reply #16 –
Ever run in to a filter that some idiot put on dry and turned it really tight? Just getting their kicks, I guess.
Well, not so funny when we have to remove the filter.
I have tried rubber strap wrenches (broke or slipped after mangling the filter exterior)
(Actually broke the best strap wrench NAPA had in Stromsburg, NE)
Oh, tried my sheet metal filter "socket" until the socket slipped.
Tried chain wrench until filter housing distorted.
Tried driving a large screwdriver thru filter body and then twisting until the filter housing tore.
Tried using a chisel on the rolled lip at the top of the filter body---still no luck.
Tried cursing and then praying and still no luck.
Tried my 6" Channellock Pliers----------------WORKED--( I do think the praying had something to do with it)
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: Changing fuel filters

Reply #17 –
They must have used shoe goo for the lube.
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: Changing fuel filters

Reply #18 –
Quote from: nitehawk –
.
Tried my 6" Channellock Pliers----------------WORKED--( I do think the praying had something to do with it)
Or perhaps you just beat it into submission with your relentless assault, and it finally capitulated.

Either way, perseverance pays off!  :thumbsup:
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"