PM 728VT one-shot oiler leak

K

kmanuele

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I've noticed that the one-shot oiler reservoir slowly drains, leaving a puddle on the floor. The owner's manual doesn't have a parts breakdown for the pump, but there's probably a leaky check valve or similar in there.

Anyone have experience with this?

thx

K
 
I haven't noticed any leaks from the pump area, but my new pm728vt seems to bleed down on the right side of the z axis column ways and fill with air in the tube. in order to push enough oil to the side of the column, I have to dump a ton of oil out of the rest of the ways.

For your situation, you might look at the hose fittings to see if they can be snugged up.

actually, I just went to youtube and typed in one shot oiler. the first link to come up was from bluehandsvideo titled One Shot Oiler Fix, and it shows our exact oiler. time to check that one out.
 
jonnyphenomenon said:
I haven't noticed any leaks from the pump area, but my new pm728vt seems to bleed down on the right side of the z axis column ways and fill with air in the tube. in order to push enough oil to the side of the column, I have to dump a ton of oil out of the rest of the ways.

For your situation, you might look at the hose fittings to see if they can be snugged up.

actually, I just went to youtube and typed in one shot oiler. the first link to come up was from bluehandsvideo titled One Shot Oiler Fix, and it shows our exact oiler. time to check that one out.
Click to expand...

My z-axis feed bleeds down also.

Not a hose fitting, unfortunately. The leak is from the table ways (feed from the lower port on the pump). The ways leak onto the chip tray, then finds its way to the floor.

Thanks for the link !!
 
kmanuele said:
My z-axis feed bleeds down also.

Not a hose fitting, unfortunately. The leak is from the table ways (feed from the lower port on the pump). The ways leak onto the chip tray, then finds its way to the floor.

Thanks for the link !!
Click to expand...
I should add that the connection to the ways is below the pump port, so it is just draining by gravity.
 
I might be a little confused by your description. Are you saying the oil just drains uncontrollably out through the x-axis ways?
can you post a pic or two?
I wonder if the pressure of the oil in the Z axis hoses is forcing the oil to come out of the x and y ways. There has got to be some sort of check valves that can be added to prevent reverse flow.... Yup. I did a google search for "One Shot Oiler Check Valve" and found some results. looking at a thread on cnc zone now.

p.s. In the video about the guy with the leaking oiler,he mentions an O-Ring at the bottom of the pump, but neglected to show the take down and installation.
 
jonnyphenomenon said:
I might be a little confused by your description. Are you saying the oil just drains uncontrollably out through the x-axis ways?
can you post a pic or two?
I wonder if the pressure of the oil in the Z axis hoses is forcing the oil to come out of the x and y ways. There has got to be some sort of check valves that can be added to prevent reverse flow.... Yup. I did a google search for "One Shot Oiler Check Valve" and found some results. looking at a thread on cnc zone now.

p.s. In the video about the guy with the leaking oiler,he mentions an O-Ring at the bottom of the pump, but neglected to show the take down and installation.
Click to expand...

Yes, drains uncontrollably, but rather slowly --- limited by the gaps in the ways. Not leaking from the bottom of the pump -- like the video.

This is response I just got from PM, which makes sense:

"The elbow on the right side has a check valve and it is stuck open. I am waiting on stock right now, but I'll send you a replacement as soon as it arrives."

K
 
kmanuele said:
While waiting I'm tempted to take that fitting off and inspect it. It's probably just a spring-loaded ball check.
Click to expand...
Since they seem to know that there are issues, maybe it’s “spring-not-loaded?”

Other than the leak, how do you like your 728VT? It’s about the largest mill I have room for as a future replacement for my Mini-Mill. Thanks!
 
ChazzC said:
Since they seem to know that there are issues, maybe it’s “spring-not-loaded?”

Other than the leak, how do you like your 728VT? It’s about the largest mill I have room for as a future replacement for my Mini-Mill. Thanks!
Click to expand...
It has been somewhat of a love hate relationship so far. I have had a few issues with it, but the more I looked into it, the more I saw people repeatedly telling folks to reach out to PM with any issues, and boy they weren't kidding. The PM tech support gnomes really know their stuff.

I plan on creating my own thread about it, now that I have most of the things resolved. I was convinced that I was going to need to replace parts, but the tech (I think his name is Charlie) suggested some things for me to try, which I did, and that has been working out very well.

My mill had a few screws loose when I got it, and I really should have gone over every inch of it before I put up up high on its new table. My Z axis on the column had a ton of slop in it. I believed it to be a bad z axis leadscrew nut but shared some closeup videos with PM and they pointed out what was probably the real issue all along. Now that I have it all snugged up my z axis seems to be great.

The included quill DRO is terrible. shamefully so. it turns itself off after a few minutes, even when it is in use, which is frustrating when you were counting on it to keep track of your z, and it doesn't kick itself back on automatically either. - Mine is actually glitching out, and PM said it was defective and are sending me a replacement. But you should just plan for replacing it with something better.

I have a few other issues, but I'll save them for my own thread.
 
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