ML7 reversing switch

  1. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire
    Yes, I think this is the case. The bearing is floating and there is a harder metal embedded in the casting to allow it to move without chewing up the aluminium. The whole cover needs replacing, there is a small crack

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  2. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire
    Any reason not to use this stuff to re-wire the switch?

    image.jpg

    looks heavier than the flex that was there (a bit perished to keep)

    image.jpg

    if not I’ve got some 2.5 singles I could use
     
  3. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire
    Ok re-wired and works fine (well,
    as fine as it was before) with the old starter on the bench. Fitted an NVR and the motor starts up, but slowly. No idea if this starter is suitable, it came off another machine.

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    I’m guessing the little green dial has something to do with it

    A6DCF44A-50D2-4FF1-A4D0-D9E7F4986DEA.jpeg

    I think the motor plate says 1/2 HP, but it’s taken a beating over the years

    image.jpg

    Clues?
     
  4. Gritineye Member

    Messages:
    1,255
    Sussex UK
    Best not to over pack that bearing, too much grease can lead to overheating and shorter life.
     
  5. daleyd

    daleyd Member

    Messages:
    7,099
    Location:
    Wrexham, North Wales
    Little dial is just an overload so doesn’t make any difference (it’s too big for that motor but no real matter).
    Pushing the green button will just energise the contactor, there’s no time delay in those starters.

    If connected direct to a plug does the motor still start slowly? I’d imagine yes, in which case possibly an over packed bearing or maybe that copper ring pushing against the cap too much. If neither of those then maybe centrifugal switch is playing up(I can’t see what type motor is, those older ones are quite often a split phase motor) or capacitor if it’s a cap start motor.
     
    Ali likes this.
  6. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire

    The cap is still off the pulley end but I did grease the other end so will investigate that. To be honest a new set of bearings wouldn’t hurt, I need to order some. I’ll check the switch too. It did run fine with the old starter on the bench, but came apart after that for further fiddling.
     
    daleyd likes this.
  7. daleyd

    daleyd Member

    Messages:
    7,099
    Location:
    Wrexham, North Wales
    If it’s a split phase motor there is usually a centrifugal switch that disconnects the second phase when up to speed, on my Elliot drill that was all gunked up when I got it, after I cleaned it out it worked fine. (I don’t know if yours has one but worth a check). I seem to remember on mine it’s on the bearing end so I wonder if you may have inadvertently pushed some grease into it when greasing the bearing?
     
  8. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire
    Not entirely unlikely - I gave it all a good clean but it was fiddly to get back together. Will have another look tonight. Thanks for all the tips
     
    daleyd likes this.
  9. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire
    Quick update, I’ve just had 15 minutes to have a fiddle. It does seem the centrifugal switch doesn’t want to disengage. I wouldn’t say it’s clean, but there’s no grease around it and it’s free to move by hand. I’d like to get it off for a proper look but can’t see how to remove it.

    The other side of the switch with the copper ring and contacts looks at a glance like it could be slightly deformed, ie., one contact is closer than the other. Need to look closer at this.

    I cleaned the grease out of the bearings and ran it without the caps on but this doesn’t make any difference, though I’ve ordered a new set anyway as they’re well past their best.
     
  10. roofman

    roofman Purveyor of fine English buckets and mops

    Messages:
    7,823
    Location:
    North West
    I have motors..your welcome to have a sniff about and see if one will do you;)
     
    Ali likes this.
  11. Ali

    Ali Member

    Messages:
    955
    Location:
    Cheshire
    Thanks mate, it’s starting to look that way so good to have a backup plan. Just when I was thinking I didn’t need the machine for a bit (dangerous thought) something has come up
     
  12. roofman

    roofman Purveyor of fine English buckets and mops

    Messages:
    7,823
    Location:
    North West
    Ok..if you need one just let me know. Will be around friday sometime as its forecast rain.
     
    Ali likes this.
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