When changing fuel filter, do you reuse the diesel drained?

I put fresh fuel in filters when changing.

Diesel fuel is a great weed suppressant.

 

I fill new filters with transmission fluid. Heard it lubricates everything but dont know if it really helps for sure. Sure doesnt hurt, been doing it for awhile now. Never use the fuel in the old filters.

 

It will hurt if u got a DPF filter.

 

If it's a cummins isx you can put them on without filling them then turn key on for 2 mins then off then back on for 2 mins. It will prime itself.

 

I dont have one, thanks for the info though.

 

Never ever fill the secondary. Secondary goes on dry and you prime it if you have a primer or purge it. Do what ever the heck you want with the primary becuase the secondary will pick up the debris. You may not think something small will get into secondary while filling but it can and will if you do it enough times. This is just advise but the littlest thing can leave you with some downtime and an injector removal.

 

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I have always filled both primary and secondary filters with clean fuel. Some engines will fill the filters by cranking on the starter. Some will get to much air and not want to even start. Been doing it this way since 1974, it works for me. But thats with a spin on filter, mayby not the newest, latest kind.?

 

Atf in both filters.