Changing C7 Fuel Filter

Yes, with a two filter system, the primary should be either a 10 or 30 micron.

The secondary (Caterpillar) filter is 2 microns.

The deed is done. Much ado about nothing on my part! I first tried to open up the hatch in the closet. Too much work and I don't think it helps much. Once I put a 500 watt Halogen underneath to use instead of a puny trouble light( old eyes) I could see that it is not that hard. The old filter came off easily. I had a super clean 4 litre oil jug and went to the local Pemex ( we are in Mexico) Brought a new funnel to take the large pump nozzle and solvent and clean rags to wipe the nozzle. Brought 3 liters home. The Secondary is way up there but other than a few lines it is easy to get a filter wrench on the filter body. The Primary filter is mounted to a frame rail and in the open. I did discover that the PO was using the wrong primary filter. It is supposed to e 30 microns but was not. The filter was way too small. I had the correct part. I also discovered that someone had extended the puke tube and recalibrated the dipstick. Before I bought this unit I did shine a powerful light through the rads and it seemed fine but tomorrow I will do more investigating. When we brought it home the first time it was over 80 degrees and we were towing my 6400 lb. PU with no overheating. Engine oil was fairly clean and only had about 4000 miles but I changed the oil and filter as well. We are good to go. Thanks everyone.

Moisheh

Secondary filter can be mounted at any elevation/height. Just figure out where you want it, measure what length hoses you will need to locate it there (keep it in the same "order" in the fuel system)-- probably easiest to have new hoses made that attach to existing hoses and go from there to the new location.

Probably most convenient to have the two filters next to each other. But, the lift pump is between them in terms of fuel flow.

And the manual primer pump is available straight, with 45 degree adapter and 90 degree adapter.

There is plenty of room for the priming pump, it goes just above the filter. It isn't that big, maybe six inches high and bolts right on to a plate above the filter. It will have to be accessed from above, though.

It'll take longer to get the floor up than installing the pump, just two bolts and a new gasket. Well worth the effort to install it, makes fuel filter changes a breeze.

Best Regards!

I get at mine from under the bed. Loosen with a fabric strap wrench and lower the
old filter a bit. Place used filter in a Zip Lock bag and place the bag in a plastic container. Properly dispose of used filter. Fill new filter as described above, place in Zip Lock bag, install and tighten. Start engine and observe for any problems. Keep towels handy....

Thanks. Brett I knew you would reply! I haven't opened up the floor in the closet but looking from below there is no room for the primer pump unless you get some type of adapter to mount it lower down. Regardless if you have to open up the floor to pump might just as well do the prefill. When I prefill a fuel filter I have a selection of plastic plugs that come with Fleetguard filters. These are the same plugs that hydraulic shops put on new hoses. I am very careful to pour into the outside holes.. My container is spotless BUT when you go to a service station the pump nozzles can be dirty. If I move that filter are there any requirements for mounting height? Can it be mounted to a frame rail? I am used to our side rad Dynasty. When you open the engine compartment door both fuel filters and the hydraulic filter are right there! Don't even need coveralls!


Moisheh

Without a pump park with the front as high as possible. Have the new filter ready to go on as soon as you get the old one out. I would fill it with fuel, not ATF. Have a bucket ready so you can drop the old one into it from above... no mess inside.

Yes, first question is does that Caterpillar secondary fuel filter have a Caterpillar manual primer pump? If not, there will be a block-off plate where you can install one.

Also, many coach makers (our current one and last one, for example)have that secondary fuel filter relocated to a much -to-access location. Just requires longer lines to and from filter.

As far as mess, take a gallon milk/water jug and cut off the top. Drop the filter into the jug for removal.

And, were it me, if you have the manual primer pump, install dry. This is Caterpillar's recommendation IF you have the manual primer pump. If not, I would fill with clean diesel, not some other fluid. And if you do fill, use the outer holes (inlets), not the center hole (outlet). That way if there are any small particles in the fluid, it will not go directly into the injectors.

My TS came with the CAT hand priming pump on the secondary filter so no prefilling is required. It's rather inexpensive (around $50) and easy to install so as long as you are there I would consider installing one. After that any future filter changes will be a breeze.

If you are not interested in doing that, I find changing the filter from below the easiest and I usually remove the air intake hose (one hose clamp). Good luck.

Lou
05 Travel Supreme Envoy