How do you disable the low oil shut-down on the HF?

Discussion in '4-Stroke Engines' started by professor, Jan 13, 2010.

  1. professor

    professor Active Member

    One of the posters mentioned doing this. 2 wires go to the sender. Do they get disconnected or joined?

  2. KeyWest

    KeyWest Member

    professor, just disconnect it I had problems with mine shutting off the engine.
  3. JemmaUK

    JemmaUK Guest

    Ok. So let me get this straight

    Your engine manufacturer has kindly included a low oil level cut out to protect the engine you just spent alot of money on... in order that if you forget to check the oil you wont be left with a expensive chunk of useless metal and a trip to ER should you have been riding the bike at the time and it decided to throw a rod through your leg and/or you into the nearest poison ivy bush...

    Why on earth would you want to disable a useful function like that? it wouldnt be difficult to rewire it in order to make it show a warning light or something of that nature instead of cutting the motor... but that would mean the engine would still be running and at the worst tearing itself to bits.

    The responsibility of any autocycle/motorcycle/motorized bike rider is to make sure their equipment is fit for use... that includes oil levels, fluid levels, brakes, pads, tyre pressures and tread, lights and the rest of the items...

    If the engine does cut out due to low oil condition that is not the fault of the motor, its designed to do that... its the fault of the rider who didnt maintain their eqiupment properly and then whines when they headbut a tree because a safety feature did what it was supposed to do...

    /rant mode: off

    Jemma xx
  4. give me vtec

    give me vtec Active Member

    I think it causes the engine to shut off at random/inconvenient times.
  5. HoughMade

    HoughMade Guest

    Some of these things are very sensitive to vibration, making even a properly maintained engine cut out in normal MB use. That being said, I would try to make it work. On my Honda, there is an external switch- I don't know about the HF, but if there is an external control, maybe mounting that diferently or something. I have my low oil switch connected and it works fine.
  6. arceeguy

    arceeguy Active Member

    Problem is that these low oil protection devices will trigger and shut an engine down if oil temporarily gets sloshed over to one side of the engine when you are making a sharp turn. (with proper oil level) The sudden loss of power is dangerous, and even if the engine returns to an upright position, it will not turn the ignition back on. Once triggered it shuts the engine off, and you have to restart it.

    The low oil protection was designed to work with a stationary engine, and will save an engine if a user decides to run their pump/generator/etc. tank after tank without checking the oil level.

    I would imagine most MB'ers will check and change their oil more often than necessary. Just look at the heated discussions about what kind of oil or fuel additives to use! I think some people take engine lubrication a little too seriously sometimes.
  7. JemmaUK

    JemmaUK Guest

    Then you troubleshoot the problem - but there is also the fact that this is what will happen if engines are used that are not designed to be used in this fashion...

    An easy fix - it sounds like the trigger for this is a rocker switch that drops and makes a permanant ignition break when it senses the oil is low either correctly or erroneously...

    Drain the engine and take out the switch - if as I suspect the thing is some sort of float on a wire or even a simple wire or something, simply bend the wire or adjust the float and test to the point where it wont cut out at normal oil levels but will when the oil is low... this can easily be done with the motor ticking over by angling the bike as it would be angled into turns.

    I personally dont really see the point of removing a useful function that you've paid money for when with a little fettling it could be useful in the current application the engine is being used for.

    If someone could post a piccy of this switch in its entirety maybe the people on here can find a way of making it work safely and properly without just abandoning it... either that or maybe a little judicious engineering work could move the switch to where it isnt affected by turning forces?...

    Not to mention the fact that if you crash the bike this could act as a cut out and save a rider from further injury...

    Jemma xx
  8. professor

    professor Active Member

    The actual switch is a little button that looks like a pipe plug with wire coming out of it.
    This weekend I will hoist up the rear of the bike, remove it and see how it works. then I will disable it.
    Jemma, a lot of times we happen to pay for things we absolutely do not want, because they were part of the package. This is one of them.
    Married people (and I am one of them) find out a similar thing.
    Only, disabling the bad features is a lot more difficult. Ask my wife.
    NOW does the above make sense?
    Last edited: Jan 14, 2010
  9. KeyWest

    KeyWest Member

    With my H.F. 2.5 H.P. engine,I have it on a pusher that I made when riding around the thing would shut off the engine.This happened at the same spot that I was riding around town,everytime I went over this dip in the road the engine would shut down??? now when I had the engine apart to remove the govenor I checked out the sensor inside the case, should of took out that bugger then but I left it in.I check the oil level every tank of gas and have not had to add any in-between oil changes.Just because they put this stuff in these things like the govenor,low oil shut off thats nice if one where to use the engine in what it was attended for but as a M.B. engine you need to make this work for your cause.In my case unplug the low oil shut off and after I did that it's all good.
  10. arceeguy

    arceeguy Active Member

    It is not a float switch. There is a little spark gap inside. When immersed in oil, the voltage from the primary of the ignition coil will not jump the gap because oil is a good insulator. When the oil level dips and the gap is exposed to air, the energy jumps the air gap and triggers an SCR to ground out the ignition primary - stopping the engine. But once the SCR is triggered into conduction, it is latched on until the coil quits producing voltage. (engine stops) Then and only then can you restart the engine.

    Pretty clever device actually, but go kart and mini-bike enthusiasts have been disabling them for years.

    We also disable the governor. And that is suposed to keep the engine from over-revving, but they'll rev up another ~1000 RPM without any issues like exploding flywheels and ejected connecting rods.
  11. professor

    professor Active Member

    I stand corrected- there is only one wire to the switch, I pulled the connector to it and ran the engine. No problem.
  12. KeyWest

    KeyWest Member

    That sounds great professor, I am glad that it worked out.Do you feel the need to have that componet working ? I dont because as a Motorized Biker I am one with my Machine and I will not neglect maitenace.
  13. professor

    professor Active Member

    Actually, I feel the need to have that NOT connected. Devices like that do have a place on stationary equipment that runs continuously.
  14. KeyWest

    KeyWest Member

    professor I agree. happy