Filling New Fuel Filter with ATF

[moisheh]

I am not a person who adds things like ATF to my fuel. Not in a modern diesel fuel system. BUT I read so often that some fill the new filter with ATF. I can see the merit of pouring in a clean liquid. How does the fuel system handle that high concentration of oil? Does the engine smoke? Thanks

[AFChap]

IF you fill it with anything, make it clean diesel. HOWEVER, the manual on my Cummins says very clearly DO NOT pre-fill the fuel filter. The manual has instructions on priming it via the ignition key before starting.

[Algoma]

There is a risk if you prefill the engine filter that you introduce contaminants that will not be filtered out. However, I fill my filter with Seafoam directly from a sealed container which cleans out the injectors. Follow the instructions and you should be OK.

[Triker56]

Use clean diesel fuel and fill the filter using the small outside holes.

[MaverickBBD]

Cover the center hole and fill with diesel from the outside until full.

[laj]

been filling my filters with ATF for over 40 yrs. including the new egr engines. it's clean, easy to carry with you, easy to fill the filter, and lubes everything down the line. I even occasionally pour some in the fuel tank. as far as starting with the filter full of ATF no problem. no it doesn't smoke or act weird just fires right up and idles smoothly. I have over 30 diesel engines usually get over 10,000 hrs out of pumps

[palehorse89]

Most all quality fuel filters come with a rubber or plastic plug in the center hole (threaded mounting hole) just for pre-filling, so all the fuel is filtered at start up. Folks can go by thier engine Bible(manual) no matter what engine, no matter if it has a hand primer pump or a electric pickup pump or nothing, but the bottom line here in the diesel world...... they do not like air! and if you get a lot or just a bit you are going to have a sputter(little air) or end up with a "no start". I have done it both ways cycling key and electric pick-up pump and pre-filling a fuel filter with diesel fuel is by far easier on starting a diesel engine after a filter change everytime. No air = A Happy diesel engine.....
Everyone has thier own method though........

[stuhly]

If you ever miss getting it to start on a dry filter you will wish you had torn that page out of the manual.

[Zoafan]

Just did my fuel filters for the first time, installed them dry and used the instructions to prime. It was very simple.

The key is do not change BOTH filters at the same time. I changed one and primed and started and then I changed the other one and primed and started.

[moisheh]

Stuhly: I like your post I changed my first fuel filter on our ISL back in 09. Did not prefill and the key thing was not working. I was in Mexico 65 miles from the nearest Cummins srevice and I had visions of spending mega baucks to clear the air out of the fuel lines. I let it rest for an hour and it finally started. If you look at a Fleetguard ( Cummins Filtration) there are instructions on the filter for prefilling. The filters come with a plastic plug for the center hole. BUT the filters I am concerned about are on my C7. The HEUI pump does not like any dirt. I do not have a primer and I havent checked but I dont think there is room for a primer without relocating the filter. So I thought maybe the ATF is the way to go. I am considering a Facet electric pump. These are used on aircraft. Our Bluebird had one from the factory and it would prime instantly. The pump is about $60.00.

[Chuck 1935]

I do not understand. The need for all this angst about a simple fuel filter ! The reason you pre fill with trans fluid from an unopened quart is that you know it is CLEAN. It is cheap and it eliminates the need for add on pumps or anything else. I subscribe to the KISS method ,(keep it simple stupid).
We can go on about lift pumps, lift pumps that are controlled by oil pressure, key on, key off or any other method that may or may not work.
PRE FILLING WORKS !

[budwilson]

Originally Posted by Zoafan

Just did my fuel filters for the first time, installed them dry and used the instructions to prime. It was very simple.

The key is do not change BOTH filters at the same time. I changed one and primed and started and then I changed the other one and primed and started.

Will it make any difference which filter you change first?

[Family Time]

Originally Posted by moisheh

Stuhly: I like your post I changed my first fuel filter on our ISL back in 09. Did not prefill and the key thing was not working. I was in Mexico 65 miles from the nearest Cummins srevice and I had visions of spending mega baucks to clear the air out of the fuel lines. I let it rest for an hour and it finally started. If you look at a Fleetguard ( Cummins Filtration) there are instructions on the filter for prefilling. The filters come with a plastic plug for the center hole. BUT the filters I am concerned about are on my C7. The HEUI pump does not like any dirt. I do not have a primer and I havent checked but I dont think there is room for a primer without relocating the filter. So I thought maybe the ATF is the way to go. I am considering a Facet electric pump. These are used on aircraft. Our Bluebird had one from the factory and it would prime instantly. The pump is about $60.00.

Cat does make a 90 degree adapter to lay the pump down horizontal for low clearance applications.

[Zoafan]

Originally Posted by budwilson

Will it make any difference which filter you change first?

I changed one closest to the engine first.