Fuel Filter Autopsy after 100k miles

glasseye

Well-known member
I finally got around to replacing my fuel filter. It was time. Last replacement was at 50k miles, now I'm showing 153k. :frown:
I decided to hack it apart to see how much crap the filter had trapped in several years and 100k miles.
IMG_20190908_124718.jpg
I cut off the cap with my angle grinder and a cutoff disk.

IMG_20190908_124801.jpg
The element was easy to remove. Getting the cap off the element wasn't. Brute force prevailed.

IMG_20190908_125534.jpg
The media was pristine. Wherever I've been buying fuel all over the continent was the right place. I could see absolutely no stuff on the element other than what I'd added with my surgery.

IMG_20190908_125559.jpg


Hengst filter from Europarts SD.
 
Last edited:

220629

Well-known member
Thanks for the information and great pictures. You should take up photography. :tongue:

The good news is that the filter media doesn't seem to show any degradation from being steeped in fuel for 100k miles.

One problem is that there could be a bunch of 4 micron particles loading up that media without it being visually obvious. I don't have any control to compare against.

Don't get me wrong. I've pushed the fuel filter changes too. I always carry a new filter and the tools needed to change it in case my dice roll doesn't go right. And... there's always the possibility of some bad fuel loading up a filter very quickly. Frequent filter changes won't always protect against that.

As much as there are those like to criticize the fuel found in North America it really isn't "The sky is falling" scenario some believe.

:2cents: vic
 

Ciprian

Spark Plugs not allowed!
I changed the fuel filter every 60k on my 2004 and now on my 2015 I change it every 50k just because it is easier to keep up with it. Never opened one up to see what was inside, but never had an issue. Good to know that it looks good even at 100k.

Sent from my VS995 using Tapatalk
 

CJPJ

2008 3500 170 EXTD 3.0 V6 OM642.993 4.182
Glasseye can you post a picture comparing the inside media (the filtered side) to the outside filter media.
 
Last edited:

Midwestdrifter

Engineer In Residence
The debris that filter is catching is sub 10 micron. You can't see it with the naked eye. Notice the filter is not a light tan color? Its dark, and if you rinsed it, it would color the solvent a light brown. That stuff can and will damage the HP pump and injectors. The clearance between the HP pumps cylinders and bores is on the order of 5 microns, tiny! If memory servers most fuel stations filter to 10-20 micron at the pump. The distributor probably filters to smaller particles than that.

Filters also will accumulate "sticky" leftovers from the refining process. Asphaltenes for example. These are smaller than 5 micron, but will stick to the filter, gradually plugging its pores up.
 

white whale

Active member
Just did replacement, must have been close to 75k since last. Opened mine too, black as could be, but didn't go further into the filter. Small issue. This is second for me. Both Hengst. Did not have issue on first go. This time just an an extra second or two to fire up. I did load in the fuel prior to install. It is fine after long trip, back to instant start. Is this considered normal ? it was only the initial start while cold, afterwards was fine. Did I miss a trick?
 

220629

Well-known member
...

Filters also will accumulate "sticky" leftovers from the refining process. Asphaltenes for example. These are smaller than 5 micron, but will stick to the filter, gradually plugging its pores up.
Good information. Asphaltenes came up in a recent thread thanks to Dennis. :thumbup: .

Asphaltenes are actually small particles, but clump together.

"Dark Fuel
Asphaltenes are a bituminous material found in most diesel fuels with the concentration varying between batches and geographic location around the world. They are a natural contaminant from the refining process of producing various fuels out of a base crude oil. Asphaltenes are not soluble in fuel and are generally less than 2μm in size in their natural state. However, within diesel fuel they have a tendency to agglomerate, forming clusters in the order of 100-200μm, making them a key component to premature fuel filter blockage. Asphaltenes are NOT always filtered out by fuel producers in the refining process due to their small size and the expense of removal."


"Do you see black specs floating in your fuel? Does your diesel fuel appear discolored and darker than normal or are your fuel filters black? Do you notice you are losing MPG? Asphaltene might be your problem!
...

Fuel Scorching Leads to Asphaltene Buildup

Simply put, the injector operates with a large amount of pressure and at a very high temperature and unfortunately it can scorch the fuel. This burning can create a black asphaltene buildup. The small pieces of asphaltenes, which contain carbon, group together forming larger clusters that can even plug the fuel filters and lead to a shorter filter life. This can cause lost MPG in your vehicle and that means you are wasting money and not getting the most out of your fuel.

Asphaltenes can be present any time of year and is all too common so be on the lookout! You should know that if you have asphaltenes, they won’t go away on their own and need to be treated by a fuel professional. If you believe you may be experiencing this issue, contact us today so that we inspect your equipment and properly treat your problem."


*****

My fuel filter change interval is every other oil change. That works out to about 28,000 miles with my typical ASSYST prompted oil change interval. Similar to Glasseye realizing 100,000 miles came around, my filter replacement schedule has at times fallen apart. Sometimes that has resulted in slightly over 50,000 miles on the fuel filter before changing.

:cheers: vic

Added:

Glasseye can you post a picture comparing the inside media (the filtered side) to the outside filter media.
The #4 picture that Glasseye posted shows the torn outside section right next to the folded back inside section.
 
Last edited:

220629

Well-known member
I was cleaning out the garage today and found the fuel filter that I removed from the 2004 . I set it aside to deal with the fuel it contained at a later date. This is later I guess. :rolleyes:

Anyway. I decided to do an autopsy ala Glasseye. It is the last time I'll bother. What a pain in the a$$ it is to get apart. Not to mention the stink of diesel fuel.

Bottom line.
The filter had at least 50,000 miles on it. The filter media looked the same as the pictures Glasseye posted above. The outside of the intact filter element didn't look quite as chunky as the Glasseye filter shown in the 2nd picture, but overall the spread open media itself was similar to his pictures inside and outside.

My thanks goes out to those that put in the effort to do a fuel filter autopsy. It ain't as easy as it would appear.

Thanks Glasseye. :thumbup: :thumbup:

vic
 
Last edited:

Top Bottom