C8.3 UCS Fuel Filters

[abyrd]

When changing the fuel filters is there any preferred order that the filters are changed.

I normally change the water separator (filter with water detector /drain) first and the smaller filter last.

I leave the water separator filter empty and have no problem starting engine, however if I don't fill the secondary filter engine won't start even with turning ignition sw. to run position several time and letting fuel pump cycle. Starts immediately if I remove secondary filter and fill with clean fuel.

The filter has a label on it warning not precharge filters on ISC engines.

[ticat900]

I always always prefill both filters on my ISL and nary a problem

[wildebill308]

Well it seems to work for you.

Bill

[wolfe10]

Actually, if you are going to pre-fill one filter, it is safer (from a dirt in fuel standpoint) to fill the primary fuel filter/water separator. That way, if there are any contaminants in the fuel, the secondary fuel filter will catch them.

But, my recommendation is to follow your engine manufacturer's recommendations for your engine. On some, that is to pre-fill. Others to install dry and use the manual primer pump (many Caterpillar engines) or engine fuel pump to prime.

[five]

My manual says not to prefill them. Tried that...wouldn't start...prefilled both and did start. So now I prefill both, but do have a portable boat fuel filter I run the diesel fuel through prior to putting it in the two Cummins filters. So I'm prefiltering the fuel before it goes in the filters for the engine. That should be enough filtering.

[wolfe10]

Another trick if you have to fill a fuel filter is to fill the INLETS, not the OUTLET.

On an "oil filter looking filter", the outer small holes are the inlets, the center large hole the outlet.

Yes, it takes awhile to fill through the small outer holes. Some have bought a pipe that screws into the center hole to make the process easier.

Brett