View Full Version : Cummins C8.3 Service

11-05-2008, 02:09 PM
I have been meaning to post this for a while now but haven?t had the time.

I needed to perform a fluid service on our DP and had been gathering the parts for a while. I changed out the engine oil and filter, both the primary and secondary fuel filters, coolant (DCA) filter and re-built the air dryer that is responsible for cleaning and drying the air supply for the air-brakes and air-bag suspension. I also added a Fumoto #F104 drain valve in place of the factory oil pan drain plug to aid in future oil maintenance.


I used Baldwin or Wix filters instead of Fleetguard as they are at least equal if not superior in quality?and a bit cheaper. I have posted this info. somewhere else?but can?t remember at the moment so here it is again.

11-05-2008, 02:10 PM
Here are the part numbers I have.

Oil Filter: LF3000 (LuberFiner/Fleetguard) ; BD-103 (Baldwin) ; 51748 (Wix) (+/- 22 quarts (15w40 HD diesel oil) with filter change including filling filter with about 2 quarts)

Primary Fuel Filter (w/water separator): FS1242 (Fleetguard, FS1242B indicates with bowl) ; BF1249 (Baldwin w/o bowl) ; S3201T (Alliance with bowl)

Secondary Fuel Filter: FF5018 (Fleetguard) ; BF988 (Baldwin) ; 33358 (Wix)

Coolant Filter: WF 2071 (Fleetguard w/4 units DCA, use at each oil change interval, test with strips) ; 24071 (Wix w/4 units DCA)

Midland Air Dryer:

Dessicant Filter: DA 33120

Coalescing Filter: DQ 6032

Air Dryer Filter Kit: DQ 6026 (includes both of the above items)

Repair Kit: DQ 6020 (includes new purge valve, 1-way check valve, turbo saver valve and all related o-rings etc.)

11-05-2008, 02:16 PM
The ENGINE OIL FILTER is located below the turbo on the driver?s side of the engine, is heavy and holds about 2 quarts of oil. Change it out AFTER the engine oil pan is emptied.

http://www.gsowners.com/attachments/photobucket/img_6785_bfcad151a870271339af11fbd8123f1d.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=OilFltr.jpg)

The PRIMARY FUEL FILTER is located on the passenger?s side frame rail across from the engine fuel lift pump (middle of the engine block) and includes a water separator with drain.

http://www.gsowners.com/attachments/photobucket/img_6785_b5215354c9f574c94aba48aab203a1c9.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=Pri_FuelFltr.jpg)

The SECONDARY FUEL FILTER is located near the passenger?s side front top of the engine, just below the valve cover and the throttle cable linkage support plate. It is a bit difficult to get to and should be accessed from the bottom. I had to snake my hand/arm between the block and wiring harnesses in order to get to it.

http://www.gsowners.com/attachments/photobucket/img_6785_212b00a26ad307c884278ef1d3c332e3.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=Sec_FuelFltr.jpg)

Both filters need to be filled with "CLEAN-FILTERED" diesel fuel to overflowing before you screw the replacement filters back on to prevent needing to re-prime the fuel system. Some coaches have a "prime feature due to the electronic fuel pumps but mine is a Bosch mechanical unit so this is the best procedure I have found. It should also be noted that with ALL FILTERS, you should fill (if possible due to mounting location) them through the "side" holes and not the large middle mounting hole as this gives the filter media a chance to "pre-filter" the fluids prior to introduction to your fuel/oil/coolant system.

The "fuel lift pump" is shown in the last photo, just forward and above the oil pressure switch.

11-05-2008, 02:22 PM
Here are two shots of the rebuilt HALDEX AIR DRYER. I couldn?t take any pics during the disassembly, cleaning and reassembly as I was fighting the clock.

http://www.gsowners.com/attachments/photobucket/img_6786_e1285cca9f21f6aab76c154a7a55912b.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=AirDryer_01.jpg)

http://www.gsowners.com/attachments/photobucket/img_6786_748bc58d0ae2d94713589f87d76dd780.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=AirDryer_02.jpg)

Basically, you dump the air bags and tanks completely, disconnect the air lines from the dryer, loosen the coalescing filter with a BIG filter wrench BEFORE you remove the dryer from the frame mounted bracket. You then remove the heater, lower bracket retaining bolts (3), loosen the stainless steel band clamp and wiggle the dryer down to the ground. It looks big but it is light as it is primarily aluminum. The Coalescing filter however IS HEAVY!

When the air dryer is working correctly, it should "pop" any residual air/moisture off when you first turn the key on and then the massive air blast when everything is fully pressurized (don't forget to shut the air tank drain valves first). Hopefully, you should have minimal moisture and no oil in the discharge as that is what the coalescing filter and dessicant cartridge are supposed to clean out or "DRY".

I will be cleaning, checking and/or rebuilding my air compressor shortly as I think it is time...and it may be leaking...which would explain the oily road grime all around it.

11-05-2008, 02:32 PM
Finally, here are some pics of my current ?ramp? setup, a engine and bed cover steel support rod (much better than those pesky hydraulic struts I was going to use) and some of the air-brake/emergency brake and air-bag leveling valves and connections. I will soon be making some structural ramps and ?cribbing? to get the coach higer into the air (+/ 12?) on all wheels for some belly pan replacement.

http://www.gsowners.com/attachments/photobucket/img_6788_a60b48b0acfba2330b163a43c02cdecf.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=Ramps.jpg)

http://www.gsowners.com/attachments/photobucket/img_6788_16cac970fa317bc61e90de07d9348661.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=EngCvr_Rod.jpg)

http://www.gsowners.com/attachments/photobucket/img_6788_f502f7b4e7c96e25e603deca7811e431.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=RRbrake_Valves.jpg)

http://www.gsowners.com/attachments/photobucket/img_6788_d34aba0e0e144a45d321559e93990245.jpg (http://s107.photobucket.com/albums/m304/ducatisti750SS/GS_Service/?action=view&current=RRlevel_Valve.jpg)

I still have to replace the broken DCA filter shut-off valve and a myriad of other items so?more to come?as usual?

11-19-2008, 02:14 PM
Ken, Looking at the side view of your air dryer I am a little confused as to what is the black cylinder that protudes on the right hand of your pic. Is that the plastic purge shield or is that the filter. I just can't make it out. I did crawl under my coach to see what my coach has and it does look like a Haldex Pure Air Plus. But the one you have on your work bench looks a bit different. The location of the air dryer on mine is on the driver side more or less between the rear axle and the Allison tranny facing downward. It looks like it might be a pretty hard job just getting to it with a oil filter strap. I don't intend to do anything right now until after the holidays. Got to get ready to fly to Miamii, Fl.

11-19-2008, 06:55 PM

They could have mounted it anywhere so your setup is certainly possible plus you are CAT powered so your compressor may be on the DS side which would explain the change.

On the lower photo of the dryer, the large round black canister is the thread on dryer coalescing filter. The unit mounts vertically with that filter pointing straight up. When you unscrew it (it takes a filter wrench with a size range of 4"-5" to remove it), the dessicant cartridge is inside. It just pulls out and gets replaced.

The smaller black phenolic item on the left in the picture is the main purge port when proper total system pressure has been reached (130 PSI on mine).

The brass valve with the slot in it just below and to the right of the purge port is the pressure relief valve. This is the item that gives a quick, short burst of air when the ign. key is first turned on.

Take some pics of yours and email them to me so I can see if there are any differences. After rebuilding mine, I am thoroughly familiar with how it works and goes together.

PS, Thanks for the number again.