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406 Fuel Filter Sediment Bowl Filter

4K views 14 replies 8 participants last post by  tlane 
#1 · (Edited)
Getting ready for SEMF-2015.
While replacing filters and fluids in my 406 (Case MB4-94) I discovered a teaspoon of black sediment in the bottom of the first stage fuel filter housing. That got me looking back to the inline fuel strainer bowl and inside the tank. Surprise! If there was a coating inside this tank, it is now sediment. The inline fuel strainer filter element has a damaged screen (two holes and is falling off the core). I will pull the suction pipe tomorrow and check the strainer too.

The filter element for the inline fuel strainer is PN: 411 477 00 15. (The entire Filter Assembly is PN 001 477 43 01)
I am not finding a source online for this part number.
Do I try and source the original replacement element or pull the entire Sediment Bowl Filter Assembly out and replace it with a disposable inline filter?
Pics attached.
Thoughts?
Doug
 

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#2 ·
I bought one right from Mercedes, to have "just in case" Scott @ EI probably has them.

Mine was around $45 CAD, but I got the whole kit part number for that is: 001 477 80 01 I can get one for you if you have no luck, also available here for more money http://www.unipaser.com/products/specials

I'm not sure but my filter doesn't screw off like yours, you just keep it clean, and replace the whole unit if it gets perforated, I think...
 

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#5 ·
Original Filter Elements are here: https://www.expedition-imports.com/Fuel-Filter-Element-_p_2132.html

We also have the complete housings as well. Complete units will use a different filter and housing, but same filtration. This uses the threaded fittings, but we have the hose barbs to screw into them depending upon what you have.

Complete Filter Assembly

Your photo looks like "algae" although no such thing actually exists.....:) We find this in diesel that has been sitting for a long time.

Cheers,

Scott
 

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#6 ·
Thank you Scott - My filter was order with you tonight.
Learned something new today.
I've hauled a 100 gallon transfer tank of diesel fuel around for 15 years and did not see algae in that tank but I turned the fuel in that tank over on a regular basis.
The UNIMOG fuel tank is my first exposure to what is described as biofilm and algae growth and now I have something to read tonight.
The recommendations are a preventative treatment routine using a biocide like FPPF's Kill-Em.
I appreciate the info and look for my order that I placed tonight.
Doug
 
#7 ·
The recommendations are a preventative treatment routine using a biocide like FPPF's Kill-Em.
Doug, as long as you're going to spend money on an additive, get yourself a multi-functional one that prevents bio-growth, stabilizes the fuel, adds some lubricity (important now-a-days) and maybe ups your cetane rating (if you believe in such things).

I use PRI-D but there are many available. I'm sure there is a thread on them here somewhere.
 
#8 ·
Doug, while you are reading, check out 'asphaltene'. That's what the black stuff looks like to me. I have had a heck of a time with it on my U-1300 having gone through probably 6 pre-filters in the last year. I've no idea why this problem just started with my truck. From what I read the cause is possibly due to heating of the fuel above a point the asphaltene is generated. Our fuel gets heated as it circulates through the IP and back to the tank. Nothing definitive, obviously.

Fleetgard/Cummins has a treatment:

https://catalog.cumminsfiltration.com/html/en/products/fuel/additives/asph_cond.html

I have not used this yet due to difficulty to find it locally. Got some waiting for me but 100 miles away! I need to go for a ride.

Bob
 
#11 ·
Bob
That black shit is diesel bugs. I think they breed in in Germany! Every Mog I've had struggled with that shit in the system. The only way to cure it is to have the tank boiled out, steam cleaned etc to remove it.
We get all our diesel from a Vallero truck stop. Our Peterbilts never have had a problem!! But my Mog toys have all had it.
A good off-road off camber Mog trip will loosen it up and then u will be dead in the water like I was.
Just bite the bullet and boil the fuel tank out--:))) There is no additive to cure it, waste of money. Clean it first then add your
lubricity/ cleaner conditioner an you will be good to go.
TLane
 
#13 · (Edited)
Hi Terry, smiling at your German bug passion!

I have cleaned my tank. Keep in mind I am talking about my U-1300 but Doug is referring to a 406. Different tanks, different pre-filters. Took it off last year and repaired some rusting under the straps. It was pristine inside and is still clean as observed with a flashlight. This black nodular, tar stuff isn't bugs (yeah, I know you are referring to algae).

Andrew, a bigger better pre-filter certainly is the right way to go. I also have a Raycor waiting for me to clear some other projects so I can get to it.

Maybe a better question is why did MB place such a small capacity filter ahead of the two Diesel filters (Primary and Secondary). Or did they?

I'm having a 'duh' moment. Suppose that pre-filter on my U-1300 is meant to catch only the big stuff, that is a strainer, not a filter? Are the MB pre-filters we get now still just 'wide open' pre-filters or are they now a smaller sieve that's clogging prematurely.

See what I'm getting at? Maybe the original MB filters were say 200 micron or whatever and some engineer thought 4 micron is better and changed the spec? That would put a tight filter with minuscule surface area in the path.

I have to admit to occasionally running a NAPA inline filter instead of the MB filter. Am I causing my own problem??? There's this little light bulb blinking over my head.

But there are still asphaltene nodules that are going to plug the first good filter they come to and it'd be worth it to me to run a conditioner that includes asphaltene abatement.

Terry, do the Peterbilts have a recirculating fuel system like the mogs or are they high pressure common rail? Bet that's the difference.

Hope this does not tug the thread too much to the side.

Bob
 
#12 ·
If you don't mind going non-stock, you can get other filters. I put on a marine style Racor with the clear bowl and drain "temporarily" while I was sorting out the fuel system on my CASE mog. It's the same kind I use on the boat. With the stock filter, you can't see if there is anything in there without taking it apart. Granted, that's not hard, but it's easier if you can just see if there is any crud or water in the clear bowl. I may go back to stock later.
 
#14 ·
Nothing sweeter than the sound of success on Saturday. Pushed the starter and she (the 406) started right up.
New inline filter from Scott at EI, fuel filters from Sean at ET, and the Fuel Tank cleaned, blasted, and coated by company near Akron, OH called Linings Inc.
So, the fuel system is good to go from tank to IP. I think Bob has it right... the black stuff in the tank and in the filters is a solid, charred substance. The pictures of asphaltene on fuel filters looked like the gunk on my filters..
The accummulation was greatest in the corner of the fuel tank where the IP return entered the tank.
I will be doing my homework on diesel fuel additives and I appreciate the recommendations provided in this thread.
Thanks to everyone who replied. Makes a big difference having experience guiding the way.
Doug
 
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