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oil return

Discussion in 'Norton Commando Motorcycles (Classic)' started by alan hodge, Jun 12, 2018.

  1. alan hodge

    alan hodge VIP MEMBER

    Joined:
    Oct 10, 2017
    gennelmen I have been making progress on my 72/73 commando project....the latest 'curseathon' involved oil return...I plumbed oil lines per old brits diagram..with intake hose on engine unhooked I pumped oil from a can into the tube on engine as I kicked it over,,,,i left oil filter off..i put the oil can to use until I saw oil drizzling out of filter head..then put new filter on and reconnected oil line to engine intake pipe and put about half a quart in (empty) oil tank...I proceeded to kick and kick with sparkplugs out but still no sign on oil return to tank....how many kicks does it take? I even unhooked hose from filter to tank and kicked just to make sure no kinks making blockage...still no oil return from that hose ...I must have kicked 100 times
    thanks
     
  2. kommando

    kommando

    Joined:
    May 7, 2005
    Depends on size of filter, took a lot of kicks on my B44 with a Norton filter, more than 100 it seemed.
     
  3. alan hodge

    alan hodge VIP MEMBER

    Joined:
    Oct 10, 2017
    'standard' size commando oil filter
     
  4. kommando

    kommando

    Joined:
    May 7, 2005
    Yep it was std but there are larger ones.
     
  5. Triton Thrasher

    Triton Thrasher

    Joined:
    Feb 10, 2009
    I just start the engine, but there’s no law against kicking it a million times if you prefer.
     
  6. Nortoniggy

    Nortoniggy

    Joined:
    Nov 17, 2010
    On a rebuilt engine it might take 30 secs or so for the oil to start flowing back into the oil tank. With the engine revving around 2000 rpm that means you have to turn the engine over 1000 times! Best of luck doing that with the kickstart. Also you will never generate any oil pressure using the kickstart. Just fill the tank with oil and start the engine.
     
  7. Triton Thrasher

    Triton Thrasher

    Joined:
    Feb 10, 2009
    And all it proves is that the scavenge sucked some oil out of the bottom of the crankcase.
     
  8. oldmikew

    oldmikew

    Joined:
    Jul 25, 2015
    not very kind to the cam to keep kicking and kicking -it will wipe off any oil or camlube
     
  9. alan hodge

    alan hodge VIP MEMBER

    Joined:
    Oct 10, 2017
    ok since i have the return hose off at tank i will take oil can and stick nozzle in hose fill it up and then reconnect and put some more in tank and stop kicking....first start a couple of months off..
     
  10. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
    There's really no point trying to fill a line that's pumping oil away from the engine.
    If the scavenge is working then you will know soon enough once the engine has started.


    After a couple of months that oil will most likely have drained to the sump (unless there is an anti-drain valve but I'm not suggesting that you should fit one) which you will then have to drain and put back in the oil tank.
     
  11. alan hodge

    alan hodge VIP MEMBER

    Joined:
    Oct 10, 2017
    no anti drain valve will put small clamp on feed line for now.. the reason i thought of squirting oil in return line was to fill it and filter and eliminate air am i wrong ?
     
  12. Triton Thrasher

    Triton Thrasher

    Joined:
    Feb 10, 2009
    I don’t think there’s any useful gain from doing that.

    The tank level will go down a little when the filter gets filled by the scavenge: you can just top up the tank.

    Clamping the hose can’t be good for it.
     
  13. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
    When the line/filter is on the feed side (so between the pump and engine) then it does make sense to prime it, but as it's on the return side and only pumping oil back to the tank then as TT said, there's no useful gain.
     
  14. alan hodge

    alan hodge VIP MEMBER

    Joined:
    Oct 10, 2017
    okee thanks men i leave alone until time for first start still need carb., pazon, alternator, wiring harness...slowly slowy catcheee monkey
     
  15. oldmikew

    oldmikew

    Joined:
    Jul 25, 2015
    let it wet sump ... if tank is empty when you come to start, take the plugs out and kick it over a few times.. that will ensure oil is splashed everywhere...then drain into clean bowl , put sump plug back , refit spark plugs and away you go...
     
  16. comnoz

    comnoz VIP MEMBER

    Joined:
    Dec 10, 2008
    Start a fresh engine with the least amount of kicks. It only takes a few slow rotations [kicking speed] on a new cam to cause scuffing, which will shorten the life of the cam.

    And you will definitely damage the cam and your leg if you try to kick it over until you get oil return....it would take hours. Jim
     
  17. comnoz

    comnoz VIP MEMBER

    Joined:
    Dec 10, 2008
    It is a common understanding that most engine wear occurs during starting. That is not because there is no lubricant on the parts. It is because the parts are moving too slowly to form a hydro-dynamic wedge. A hydro-dynamic wedge is similar to a hydroplaning tire or a water ski. It only requires a tiny bit of oil to float the parts a few millionths of an inch - AS LONG AS THERE IS ENOUGH SPEED. This tiny amount is all it takes to avoid metal to metal contact and damage. This is not only true with the cam but all the moving parts in the engine.

    That is why it is a good idea to use the least amount of cranking to start a fresh engine.
    A drop of oil or assembly lube on the moving parts during assembly is all that is needed to protect the parts during starting. Just make sure the crankshaft, oil pump and oil lines are full of oil so there is lubrication as soon as the motor starts. Start it quickly and bring it up to 2000 to 2500 rpm for a few minutes.

    After the motor runs for a few minutes you should get oil return to the tank.
    That is a dangerously delayed method of making sure you have oil delivery to the motor. I would suggest an oil pressure gauge at least temporarily plumed into the overhead oil line to make sure you get pressure within 15 or 20 seconds of starting. The oil reservoir in the crank will supply enough lube till the pressure comes up. Jim
     
  18. Bernhard

    Bernhard

    Joined:
    Apr 20, 2011
    Just take one of the exhaust covers off, then pour oil into it to lube the cam, then start the engine, but do not rev it until the oil filter is full and you see oil coming out of the return pipe inside the oil tank.
     
  19. oldmikew

    oldmikew

    Joined:
    Jul 25, 2015
    Good idea and better than nothing but the oil will not make its way onto the actual lobes until the Cam rotates bywhich time it could be scuffed
     
  20. Triton Thrasher

    Triton Thrasher

    Joined:
    Feb 10, 2009
    Why?