How to test whether fuel filter is clogged

Discussion in 'Parallel Universe' started by jlpp, Oct 7, 2012.

  1. jlpp

    jlpp Adventurer

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    I've had some trouble with the fuel quality while travelling in central/southern Asia over the past couple months. In another thread I mentioned that the original fuel pump was failing (overheating, it appears) and how I found what seemed to be a suitable Bosch replacement at a dealer in Bishkek. Well, that replacement failed in India. It went about 2,500 miles before dying outright.

    I'd like to get some idea whether it died because it was working too hard to push fuel through a partially clogged fuel filter, whether the pump wasn't properly speced for the application (e.g. in terms of liters per minute), or something else. I want to do this to help me decide whether to spend $500+ getting a new pump/filter assembly to India or whether to keep experimenting with $40 pumps from Bosch.

    I'd like to test whether the filter is shot, first. When I had the pump failures I pulled the hose off the pumps and blew through the hose into the filter and, after pushing the remaining fuel out the other end, air does pass through. I've tried the same blow test on a new, generic fuel filter that was about the same dimension and it had about the same resistance.

    Is this a fair test? Is there some other test I could try?
    #1
  2. Hicks

    Hicks der Ɯberluber

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    and where did you find a fuel filter on the 800GS?
    #2
  3. ebrabaek

    ebrabaek Long timer

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    Flush the tank, and blow through the screen backwards... not much else you can do...
    #3
  4. Snowy

    Snowy Long timer

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    Interesting.

    I looked through the genuine BMW repair DVD.

    I would be tempted to fit an inline HP filter, after looking at the diagrams. Possibly even remove the screen altogether.

    Another thought that occurred was replacing the in-tank pump with an inline HP one. Extra tank volume.

    Finding somewhere to mount would be the fun part.


    I might give this some more thought. I'm tempted to keep the F800 and completely cut it up and rework everything.
    #4
  5. jlpp

    jlpp Adventurer

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    There's a mesh strainer below the pump in the tank but that's not what I'm referring to. I'm talking about the metal canister above the pump but in the tank. That's the fuel filter. Wish I could replace it without replacing the entire pump/filter/gauge float harness. But since I can't find a replacement part, at least I want to know whether this filter is causing the pumps to fail.

    Any other ideas on testing the filter?
    #5
  6. LukasM

    LukasM Long timer

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    For those that don't know, this is what the fuel pump for the F650GS twin/F800GS (same part) looks like.

    The round metal canister under the blue connector is the filter.

    [​IMG]
    #6