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?
#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.
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.
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.
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.
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.
SCA is Supplemental Coolant Additive. Just sayin'
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.
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?
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.
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.
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 (https://www.amazon.com/dp/B01L1DKSM4)
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)
They must have used shoe goo for the lube.
Or perhaps you just beat it into submission with your relentless assault, and it finally capitulated.
Either way, perseverance pays off! :thumbsup: