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Tales of woe

Discussion in 'Norton Commando Motorcycles (Classic)' started by Woody850, Apr 19, 2019.

  1. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
    Hello All,
    well just began to get my 73 850 ready, primary chain a little tight, camchain (feeling through the hole in my Mk III Cover) far too tight. I couldn't even find a loose spot caused by the cam not being on lobe.
    Of came the cover and I found the spring of the cam seal stuck to the cover.
    I mounted the intermediate plate I got from AN but can not find the correct way to set the 4.5 mm play.
    If the cam is opening a valve should the mesurement be made pushing the chain down and then lifting it.
    Another question on the oil pump was a large flat washer, I had earlier bought the conical seal which I had been told should be used on the Mk III Cover. Is this correct or do I need the flat sealing washer?
     
  2. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
  3. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
  4. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
    Thanks L.A.B. I believe the conversion was correctly done. Is the bushing screwed into the pump housing?

    I have tried to post a picture with not much success though.
     
  5. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
    Just a press fit. Edit: Your photo shows it has a Mk3 pump bush.

    It works as a link.
    https://photos.app.goo.gl/8oBStgnCDHorxLNn8
     
  6. Woody850

    Woody850 VIP MEMBER

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    Sep 30, 2017
  7. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
  8. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
    I can't tell from the photo but it's the total up and down free movement, check at various crank/cam positons.
     
  9. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
    Ok, I tried with turning the engine in fifth gear two links at a time of th cam chain and took measurements. At the tightest point when the cam was under load I had 2mm, the slackest point was 9 mm.
    I'm stumped how to find the correct setting.
    Should I be turning the engine backwards or should I replace the chain?
    I am using the intermediate plate from AN!
     
  10. L.A.B.

    L.A.B. Moderator VIP MEMBER

    Joined:
    Nov 20, 2004
    Fifth gear?




    Have you tried holding the tension off the chain with a socket on the camshaft nut?
    With the spark plugs removed then you should be able to turn the crank/camshaft by the camshaft nut.



    That, I couldn't say.
     
  11. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
    Sorry I am getting so mixed up with the T140 restoration running alongside my Norton, should have been fourth.

    You have given me food for thought now, in principal always pulling the cam back in different positions to find the tight spot of the chain and to deter 4.5 mm play.

    Can't wait to try but Madam will kill me if I dissappear tomorrow in the garage.

    Thanks again L.A.B.
     
  12. jimbo

    jimbo VIP MEMBER

    Joined:
    Sep 25, 2004
    Be aware that the feed bush can be inserted either way into the pump, however the spigots are not the same OD and one will be snug( correct) and the other will not. Also the MK3 pump needs a wider landing machined into its side than the earlier ones in order for the larger OD bush to sit on it squarely. Here are some photos showing the differences, I used an earlier pump and machined the area flat. Also showing the check valve.

    DSC09620.JPG DSC09621.JPG DSC09626.JPG DSC09633.JPG DSC09632.JPG
     
  13. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
    Good to know that about the Mk III Pump. Does the later pump have more in it compared to the older one regarding flow or pressure?
    I myself have the later one fitted but would like to fit an inconspicuos pressure gauge, I had thought of coming in on the banjo bolt at the back of the casing.
     
  14. Woody850

    Woody850 VIP MEMBER

    Joined:
    Sep 30, 2017
    Back to the cam chain tension, I did as L.A.B. said and turned the camshaft anti-clockwise at intervals and managed to get a constant slack in the chain to which I made the adjustment of 4,8 mm play.
    Many thanks L.A.B.
     
  15. jimbo

    jimbo VIP MEMBER

    Joined:
    Sep 25, 2004
    MMK3's and earlier Commandos have the same oil pump guts, I run a oil gauge feed off the rocker arm plate.
     
  16. Woody850

    Woody850 VIP MEMBER

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    Sep 30, 2017
    Could you post a picture of it Jimbo please.....
     
  17. jimbo

    jimbo VIP MEMBER

    Joined:
    Sep 25, 2004
    sure I'll get some photos. I made an adapter to tap off the right side rocker spindle plate on the head. I used an electric gauge with a sender. Running the voltage off the switched ignition hot wire, caused the readings to fluctuate with variable voltages in that circuit , so I wired it directly to the battery.That caused another problem as the sending unit would read just a little amount of oil pressure, and send a small voltage to the gauge draining the battery while the bike was not running. So I had to use a relay tripped by the hot side ignition. Long story but I did not want to run a small oil line to the gauge as I thought that could be a point of a leak or failure.
     
  18. jimbo

    jimbo VIP MEMBER

    Joined:
    Sep 25, 2004
    heres some photos of the electric oil pressure gauge rig.


    DSC09838.JPG DSC09839.JPG DSC09840.JPG DSC09841.JPG DSC09842.JPG
     
    Deets55 likes this.
  19. Woody850

    Woody850 VIP MEMBER

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    Sep 30, 2017
    Looks very good jimbo with nice tidy electrics.
     
  20. jimbo

    jimbo VIP MEMBER

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    Sep 25, 2004
    thanks I just cleaned that area up, in the past there was a lot of getr done!
     

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