Epic - When You Changed Your Fuel Filters Did You Notice?
 

Did you notice the new frame mounted/DFCM filter has what appears to be a really fine membrane(Feels like Plastic) on the inside or I.D. of the filter instead of on the outside. This could be what is supposed to take the place of the membrane that is on the O.D. of the 6.4 filters, which I could be wrong on this one but is supposed to be the water seperator. I this is true I don't know that the new design is better for one main reason, wiith the membrane on the inside of the filter it will not prevent the pleated media from holding water. This water could build up over time and not drop to the bottom of the bowl. At least with a membrane on the outside of the filter the water just hits it so to speak and falls to the bottom like water off of a ballon.

Anybody else's thoughts and please keep it about the filter not a bash on Ford or any of their suppliers.

I didn't notice this with my filter change but the filter I used was purchased around May of last year.
I always keep one in the truck so when it is time for a filter change, I use the spare in the truck then rotate out with a newer one.

Are you saying this design wasn't included on the FD-4615 filters previously?
If these are slightly redesigned, I wonder if it's worth starting over with new filters?
I suppose there’s no guarantee we would get a new one from DFO stock, either.

When I first saw the inners of a Ford 6.7 filter, I did not see any water block membrane. I have since seen the inner portion that you speak of.

The 6.4 filter that you speak of was a Racor filter which is said to be the exclusive water block construction.

I am wondering if by putting it inside the filter ,they are able to get around Racors patent? Or if it is even the same material? Even if it is, I am undecided on which way is better...If this is a end run around Racor, then I would tend to think that Racor being the first likely tried it both ways and decided to block the water before it contacted the filter.

Another way of looking at it is that they took Racor's design and improved it?

One thing that comes to mind is that by putting it inside, the surface area will be less, and likely water would be able to squeeze thru the membrane easier due to more fuel flowing faster thru a smaller sized medium.

More questions than answers.

Hey Doc,

When you disassemble the DFCM filter, you will find a porous plastic cylinder inside the primary filter media. I don't have any thoughts on whether it's best for it to be on the inside or outside of the primary filter. Here's a video of the tear-down:

Ford 6.7L Diesel Fuel Filter Inspection - YouTube

Filtration + Separation - Fuel filtration: Protecting the diesel engine

"The most typical filtration media found in such separators is hydrophobic barrier media, such as silicone treated cellulose. This media separates water on its water repellent surface. Water in the fuel is rejected and beads up on the upstream side of the media. As more water is rejected, beads coalesce into large drops, and drain into a collection cup. Another successful media is hydrophilic depth coalescing media, such as glass micro-fibre. This media has high affinity for water. As water in the fuel encounters the media, it associates with the glass fibres, where it is joined by more water over time, growing into massive drops. The water moves through the filter with the fuel. On the downstream side, the water falls out of the fuel flow into a collection cup due to its higher density, while the dry fuel rises out the filter exit. "

Who knows which is best method. Ford engineers knew or believed water in fuel was an issue before the 6.7; I want to trust they made a good engineering decision on the new fuel filter.

Bob

I do recall seeing that the first time I just didn't put the 2 together until know. Anyway I don't know enough about filters to say either way it struck me as different.

I remember the white hard plastic filter piece on the inside of the filters.
I was thinking this topic was referring to a thin layer of plastic on the outside.
Now I know what's being discussed. Didn't occur to me prior.

I changed my oil and fuel filters today. Inspected the DFCM bowl very carefully and cut open the filter housing for the engine mounted filter.

I found one thing, a piece of foil from the top of one of the fuel additive bottles. Everything else was perfectly clean and free of any substance that could be deemed metallic. The filter media was dirty though, fairly saturated with brown dust.

My motor has 97,670 miles on it and the fuel filters around 15,000. (every other oil change.)

Only surprise to me was that it took longer than I thought it would to purge the air with key on strokes. I thought it might be done as I could hear the air hissing out but it still took about 2 sec for the engine to start when I started it.

After watching Epic's video I noticed it took a little longer for his truck to start. So when I changed my filters out I did the keys turns 6 times for 30 seconds to prime the system. Then I let the truck sit for about 10 minutes and repeated the process, by the time I completed what was actually the 12th key turn all the hissing was gone and the truck started right away with no delay.

Oh and filters where clean and no signs of metal debris.