Sag 12 Headstock Not Pumping Oil?
Close
Login to Your Account
Results 1 to 8 of 8
  1. #1
    Join Date
    Sep 2006
    Country
    CANADA
    State/Province
    Ontario
    Posts
    177
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    2

    Default Sag 12 Headstock Not Pumping Oil?

    Hi everyone, I finally got around to cleaning the Graziano Sag 12 transmission and changed the oil in it. I also drained the headstock oil and put fresh oil in it, got it wired up and it started right up, first time I have heard it run in almost 15 years. Now the problem is that the top sight glass there is no oil moving. Is there a way to prime the headstock, I didn't want to run it too long since it's been sitting for so long. Any help would be appreciated.
    Thanks Mike

  2. #2
    Join Date
    May 2002
    Location
    Auckland, New Zealand
    Posts
    4,540
    Post Thanks / Like
    Likes (Given)
    1986
    Likes (Received)
    557

    Default

    Mike,

    I can't see oil in my tell-tale window either, but that is because the glass is stained or dirty.

    How about first lifting the headstock cover and seeing if oil is flowing onto the aluminium oil distributor plate (photo courtesy the late Texas Turnado).

    If the pump isn't working/self-priming, perhaps try fitting some flexible tubing to the pump inlet pipe and feeding it some oil from above the headstock cover level? Sorry about the mist of oil covering you by now

    I haven't looked on my lathe, but the other photo (spindle removed) shows there is a short copper pipe on the suction/inlet side of the pump.

    The photo was taken by a PM member (sorry I can't recall your name) who changed out his bent spindle many years ago. Because the spindle had been removed, the oil pump inlet pipe can be seen.

    Or...how about fitting a length of clear tube to the outlet pipe and suck....

    An old trick used on tired engines with external oil pumps (e.g. Holden V8's) was to remove the oil pump and coat the pump gears (or vanes) with Vaseline. They would self-prime after doing this, and continued to do so thereafter.


    sag-12-head-stock-oil-distributor-plate-texas-turnado-01.jpg emptycase.jpg
    Last edited by Peter S; 05-10-2020 at 07:35 PM.

  3. #3
    Join Date
    Dec 2010
    Location
    Sydney Au
    Posts
    494
    Post Thanks / Like
    Likes (Given)
    67
    Likes (Received)
    70

    Default

    Not working or just the pinwheel not spinning? Have found the fit of the cover can affect the latter....and of course, running the spindle in reverse is the other oil free situation.

  4. #4
    Join Date
    May 2002
    Location
    Auckland, New Zealand
    Posts
    4,540
    Post Thanks / Like
    Likes (Given)
    1986
    Likes (Received)
    557

    Default

    Quote Originally Posted by BillE View Post
    Not working or just the pinwheel not spinning? Have found the fit of the cover can affect the latter....and of course, running the spindle in reverse is the other oil free situation.
    Bill,

    I don't think the Sag 12 headstock sight glass has a pin wheel.

    I am almost certain the Sag 12 headstock oil pump works equally well when turned in either direction. Texas Turnado explained how it worked in his rebuild thread:

    Quote from Texas Turnado: "The eccentric bronze bushing is free to rotate in the housing, but has two stops. The friction from the vanes cause it to rotate against the first stop, which is set to hold the eccentric in the correct position to pump oil out thru the correct port. When the rotation is reversed, the eccentric rotates with the vanes until it hits the other stop, which is positioned to pump oil out thru the same port as before - a rather simple but clever design, me thinks...."


    p5270029.jpg p5270027.jpg

  5. Likes BillE, ACHiPo liked this post
  6. #5
    Join Date
    Jan 2005
    Location
    The Netherlands
    Posts
    6,044
    Post Thanks / Like
    Likes (Given)
    292
    Likes (Received)
    1629

    Default

    I had the same problem on my 12S
    took out the pump Cleaned it and filled it with oil while I had the tube off
    That did not work
    Then I realised the vanes had some play
    I then put in a somewhat oversized centre tube (see picture in previous post)
    After a while it pumped again
    I would remove the lid anyhow because it can take a while before you see the oil

  7. #6
    Join Date
    Dec 2010
    Location
    Sydney Au
    Posts
    494
    Post Thanks / Like
    Likes (Given)
    67
    Likes (Received)
    70

    Default

    Quote Originally Posted by Peter S View Post
    Bill,

    I don't think the Sag 12 headstock sight glass has a pin wheel.

    I am almost certain the Sag 12 headstock oil pump works equally well when turned in either direction. Texas Turnado explained how it worked in his rebuild thread:

    Quote from Texas Turnado: "[I]The eccentric bronze bushing is free to rotate in the housing, but has two stops. The friction from the vanes cause it to rotate against the first stop, which is set to hold the eccentric in the correct position to pump oil out thru the correct port. When the rotation is reversed, the eccentric rotates with the vanes until it hits the other stop, which is positioned to pump oil out thru the same port as before - a rather simple but clever design, me thinks...."
    Interesting. I think I'd have to see in the flesh what John described to get my head around the pump operation he's describing.

    Do wonder what happened with his lathe too, got the impression, the stepchildren(?) weren't likely to appreciate his labours.

  8. #7
    Join Date
    Feb 2010
    Location
    ch
    Posts
    2,504
    Post Thanks / Like
    Likes (Given)
    216
    Likes (Received)
    330

    Default

    i dont know about this pump, but often the top cover needs to be ground to reduce the clearance.

  9. #8
    Join Date
    Sep 2006
    Country
    CANADA
    State/Province
    Ontario
    Posts
    177
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    2

    Default

    So I took the top cover off and the oil is pumping fine, it was just hard to see it in that sight glass. Thanks for everyone's help.

  10. Likes Peter S liked this post

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •