Engine/Transmission (1994 - 1998) Fuel filter-just curious

[johnjackson]

I just changed my fuel filter again and the used filter allways comes out black. No other dirt, rust, water or anything, just ink black. Is this normal? Does everybodies filter come out black?



Thanks



John

 

[illflem]

My understanding from the Chevron diesel website is the black we all see is fine metal debris that gets in the fuel in the delivery process from pipes, tanks, pumps, etc. Consider how many gallons of fuel flow though your filter before you change it and the black stuff really isn't that much.

 

[grtescpa]

Originally posted by johnjackson

I just changed my fuel filter again and the used filter allways comes out black. No other dirt, rust, water or anything, just ink black. Is this normal? Does everybodies filter come out black?



Thanks



John

I don't know how long you wait between filter changes but I tend to cut what Dodge recomends in half. I change my fuel filter every 6k. Its not as black so I know I am increasing the life of the injector pump. Getting rid of unwanted debris caught in the fuel system sooner.

 

[moparguy]

First of all, take every thing you read on the Internet with a grain or two of salt.



Now for the opposing view on changing filters. An argument can be made that your injection pump would be better served by changing the filter at twice the recommended mileage rather than half.



Think of a filter as a series of holes. Some big, some small. Whatever you're filtering will follow the path of least resistance. That would be the big holes. Since the larger passages are caring the fuel (or air in the case of a air filter), they will stop particles larger than the passageway. Of course smaller contaminates will pass through.



As the larger passages clog up, the fuel (or air) is forced to follow the next available path of least resistance, or the smaller unclogged holes. They in turn filter out smaller particles.



Filtering out smaller and smaller particles is a good thing.



This process will continue until the filter clogs and a power loss is noticed. Filters should be changed before that happens since if the application generates sufficient suction, a totally clogged filter can start to disintegrate and then really bad stuff starts to happen.



Will our trucks cause a filter to come apart, I don't know. But I change fuel filters on a much longer schedule than the book calls for and it works for me. I do drain a little fuel at each oil change and it's always clean.

 

[illflem]

Asphaltines that are in all diesel fuel to some extent will also stain your filter black, read about it here http://www.baldwinfilter.com/engineer/94_14.html

20k or once a year intervals work for me but just 10 miles on one bad tank is all it takes to plug one.

Best bet is a fuel pressure gauge on the outlet side of the filter. Just saving a couple of needless filter replacements will pay for the gauge.

 

[HEMI®Dart]

Caterpillar has a new 2 micron fuel filer. I think they only make them for their engines. I believe it is a screw-on like ours.



http://www.caterpillar.com/products...d_filters/_filters/high_eff_fuel_filters.html



#ad

 

[moparguy]

Good point Bill F. , a post filter gauge is the best way to monitor fuel filters. I did read the recent thread on that very subject. Guess it's time to source out a gauge and necessary fittings.



Hemi, I wonder what percentage of 2 micron particles our Fleetguard filters remove? Or what the efficiency claim is?

 

[grtescpa]

Originally posted by moparguy

First of all, take every thing you read on the Internet with a grain or two of salt.



Now for the opposing view on changing filters. An argument can be made that your injection pump would be better served by changing the filter at twice the recommended mileage rather than half.



Think of a filter as a series of holes. Some big, some small. Whatever you're filtering will follow the path of least resistance. That would be the big holes. Since the larger passages are caring the fuel (or air in the case of a air filter), they will stop particles larger than the passageway. Of course smaller contaminates will pass through.



As the larger passages clog up, the fuel (or air) is forced to follow the next available path of least resistance, or the smaller unclogged holes. They in turn filter out smaller particles.



Filtering out smaller and smaller particles is a good thing.



This process will continue until the filter clogs and a power loss is noticed. Filters should be changed before that happens since if the application generates sufficient suction, a totally clogged filter can start to disintegrate and then really bad stuff starts to happen.



Will our trucks cause a filter to come apart, I don't know. But I change fuel filters on a much longer schedule than the book calls for and it works for me. I do drain a little fuel at each oil change and it's always clean.

To each his own but I would rather change it sooner than risk all that crap being sucked into the injection pump with out warning. All it takes is a dirty load of fuel and how would you know?? Only by draining at oil change? I have seen the filter loaded with debris and still have the fuel come out clean.

 

[rdrose]

john i guess no one really gave you the answer you where looking for. mine is always black after 10k mile, i change mine every other oil change. it would be best to change it with the oil but there a little too much $. hope this helps and all the advice above is great too. all this is good to know.

 

[johnjackson]

Thanks rdrose and all for all the fuel filter input. I buy most of my diesel from the local fuel and oil co. so pretty clean. What I notice , if I get lazy on the filter change interval, I start loosing power at about 15k miles. Can't peg the boost gauge when I floor it in fourth gear (30#), so I guess maybe the manual is correct with a 12k interval. Glad to hear I'm not the only one with a black filter.



John