990 fuel filter idea

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by Helios, Apr 18, 2013.

  1. Helios

    Helios Been here awhile

    Joined:
    Apr 24, 2007
    Oddometer:
    388
    Location:
    Boise, ID
    So here is my evil master plan..
    I use a split stream filter sock on the left tank that filters to 40 microns
    and use a 50 micron filter between the tanks. (could be changed to any micron, these filters are in place and have been for some time)
    this way all fuel put in tanks is filtered to 50 microns before it even gets to the prefilter on the fuel pump.
    My understanding is the prefilter sock on the pump is a 50 micron filter, so if this is accurate, I could flush the left tank and remove it entirely as my other filters are doing that job.
    I am also planning on removing the 10 micron filter from the fuel pump and installing a 10 micron automotive filter in the airbox.
    I am also installing a fuel pressure gauge after the 10 micron filter so I can monitor the pressure after all filtration is done to make sure it stays at least 50psi. this is necessary due to the regulator will no longer be able to detect a drop in pressure as it is no longer last in line (after 10 micron filter) I am not too worried about this as the automotive filter will have many times the filtration capacity the the stock 10 micron does and I will have a eyes on gauge on my dash to monitor pressure in real time.

    benefits of this mod..
    1. I can get 10 micron filters in auto parts stores anywhere..
    2. No longer dependent on KTM filters
    3. Fuel pump will never starve for fuel, cavitate and burn up
    4. I have a 10 micron filter after the quick disconnect and before the injectors.

    Down side of mod
    1. possible fuel pump damage if prefilters fail (unlikely)
    2. internal fuel pressure regulator on pump cannot detect a clogged 10 micron filter as it is no longer last in line. (reason for pressure gauge)

    Thoughts??

    -H
    #1
  2. guglemonster

    guglemonster Crivens!!!

    Joined:
    Aug 28, 2007
    Oddometer:
    977
    Location:
    Italy
    hell as far as I know I cannot cross reference in here :)

    so..

    your idea is a bit crazy

    first of all the dirt from the petro can star encrusting the tanks and be released in the most unconvinient time in for of big particles, like dendruf :D:D:D

    you cannot leave a pump unguarded, think if the stupid screw that holds the negative cable get loose, the pump will suck it and get destroyed

    you must have a screen, it'a a must

    you plan to put a 10micron filter outside the tankis simply perfect, I am running this set-up on my bike and other ten... it is just that aoutmotive filter are 5-8 microns, not 10 :) and you need a 5 micron for a modern fuel injection :)

    the idea to use a mesh in just one tank will force you to spend half an hour at the petro station and everybody will hate you... I know it becouse I was refueling using a Profill filter for two years and got my teabag (original) any way clogged from small particles.

    the original KTM filter is much more selective than 50micron, I think we are much closer to 20... that's way it clogs so easily

    I run my own design, it's a 5 layer 3d filter (3d beacouse the 3 first layers are thick, like wool creating a much bigger surface where the bigger stuff get cought leaving lenty of space for the petrol to go through) and the 4th layer goes down to 30 (but le'ts pretend it's 50)

    [​IMG]


    it's almost twice as bigger as the original small one and a big automotive filter before the airbox

    [​IMG]

    here protecetd inside a tyre tube

    I do not have a pressur gauge, the bike runs like hell, I will never face a pump cavitation and my huge automotive filter will survive the worst part of 50.000 km of the dirtiest petrol you can immagine while the screen filter will block anything the pump would not be able to swallow, it has also water blocking capability

    here after 10.000 km of east block petrol opened for forensic analysis

    :D:D:D:D:D

    [​IMG]


    [​IMG]

    [​IMG]


    [​IMG]


    filter was working without any problem and I just cut it for testing pourposes

    let me know if you want to try my set-up :)

    :D:D:D:D:D

    don't ermove the teabag, or you'll suffer, believe me

    :D:D:D:D:D

    forgot one thing

    in case o pressure drop, the bike will not work... and you will see it much sooner, below 3,5 atm the system shuts down, and you will have fuel starvation befor a pressure drop due to clogged filter

    if you have got teabag clogging you may risk cavitation, if you have main filter cloggin, the bike will siply switch off :)

    her a pic of my monster filter :)

    [​IMG]


    [​IMG]


    ain't it a beau ??
    :)

    here the comparison between old and new ktm filters... the dwafrs

    [​IMG]



    ;0
    #2
  3. guglemonster

    guglemonster Crivens!!!

    Joined:
    Aug 28, 2007
    Oddometer:
    977
    Location:
    Italy

    forgot to answer to this :)

    if the pressure goes above 3.5 bar, the regulator will cut in anyway for the back flow pressure wave coming from the filter

    a big automitive filter is supposed to run much more petrol than a 1000cc bike, get some 5.7lt petrol filter and you may never change it again :)

    mine is for a 3.2l v6 engine, considered a big bore here in italy

    :rofl:rofl:rofl:rofl:rofl:rofl:rofl:rofl:rofl:rofl:rofl
    #3
  4. Helios

    Helios Been here awhile

    Joined:
    Apr 24, 2007
    Oddometer:
    388
    Location:
    Boise, ID
    Thanks for the reply!
    I have been filling the 40 micron sock for quite a while, it does not fill as fast as an open tank but it is more than manageable, it might take twice as long to fill that side. this is why I dont have one in both tanks! As far as dirt lining the inside of my tank.. I would flush it really well with a cleaner plus our fuel here in my area is not so contaminated. I have though about leaving a strainer on the pump in place of the sock filter. something around 40 microns, as a just in case kind of thing.
    IIRC most prefilters on intank fuel injections pumps have a 50 micron filter.

    -H
    #4
  5. guglemonster

    guglemonster Crivens!!!

    Joined:
    Aug 28, 2007
    Oddometer:
    977
    Location:
    Italy
    hey, my pleasure :D:D

    how are you going to fix the strainer to the pump?

    40microns are just good, it's std automotive spec :)

    if you can put the strainer i'd go for it, big automotive filter outside and live happily

    :D:D:D:D:D:D:D

    you will feel also a faster throttle respons, don't know if it is placebo or not, but it makes you grin :)

    :D:D:D:D:D:D
    #5