Precision Matthews PM-728VT Mill Leaking Way Oil

[chipinator]

Hello. I hope everyone is staying well. I have a brand new Precision Matthews PM-728VT mill that I haven't had an opportunity to use yet. I filled the tank with Quick Slide 68 way oil in preparation for use. I noticed that when standing in front of the mill, oil is pooling onto the drip/chip pan near the front left mounting bolt. I can't determine where the oil is leaking from. Anyone have any ideas why this may be occurring? Where it might be coming from? Any guidance would be most helpful. Thank you.

 

[Tom1948]

I have a 727v with no problems so i am not familiar with your model. However, contact pm and i am sure they will advise. I found them great to work with.

 

[chipinator]

Hey Tom1948. Thanks for replying. I actually emailed PM with pictures a couple of weeks before posting here, albeit not the greatest seeing Quick Slide 68 is clear, and of course a description of what is occurring. PM wasn't definitive on what could be causing the issue and that basically I would have to do some inspecting to find out the source. They were supportive on if/when I found the issue and that parts would be available to fix. Man I don't want to disassemble this thing! That's not going to be a good day if I have to!

 

[mksj]

It seems to be a common problem with bench style mills, most likely because of gravity causing the oil to seep from the pump to the oil lines. It may be some dirt or a seal at the pump, but the typical fix would be to add a low pressure cracking check valve. These open with low PSI, and then close once the pressure is relieved. You would need to determine the tubing size or thread of the oil line going into the pump. See previous thread on the PM-833 and I also have seen this reported with some knee mills.

PM 833TV One shot question

Since I received my 833 it has leaked the oil from the one shot system. It took about 2 weeks and every bit of it leaked out. I did not pinch any lines when I set it up, I was very careful about that. I can not find a leaking fitting but if I had to guess based on where it is, I think it is...

www.hobby-machinist.com

 

[Tom1948]

Thats a bummer chipinator. My mill does not have that. I know you want and expect things to work as they should but can you settle for hand lubricating things until pm can figure it out? I believe they will put forth the effort to get to the bottom of it. They have too much at stake not to.

 

[chipinator]

Hey mksj. Thanks for the reply. Interestingly, the way oil is not pooling or dripping around the pump/reservoir but down onto the front left mounting bolt; it's gotta be coming from the X or Y axis somewhere. I'll do some searching around for a "low pressure cracking check valve" and see what I can come up with. Thanks for the post as well. I'll definitely read to see what I can learn.

Tom1948 - I haven't used the mill yet. I had set it up on its stand, filled the reservoir, gave it a couple of pumps to make sure the ways were indeed being oiled which they are and began another project that I needed to complete before beginning to use the mill; small garage, trying to make space. I don't believe PM will be able to figure it out as their email reply basically stated that I would have to do the inspecting to find what's causing the issue but they were there for parts when I do find the root cause.

 

[Bwolf]

Pretty funny to read this since I just discovered the same thing on my new 728 this morning. Had a large puddle in the back right, but best I can see is it’s coming from the left front and running back since the stand isn’t level yet. Cleaned it up and currently watching to see where it’s coming from. The amount of oil seemed excessive considering I really haven’t given the one-shot any use.

just logged on to try to find a plumbing drawing to see where the one-shot lines go. Though I had a loose fitting, but so far those seem dry.

I didn’t even fill the oiler. Just working with what it arrived with.

 

[chipinator]

Hey Bwolf. Thanks for taking time out to read the post. My cursory look included the oil line fittings and they looked dry as well. I was wondering if anyone else may be having the same issue or not. As soon as my other projects get completed, which I'm very close on, I'll be able to take a closer look.

Have you considered contacting PM to report the issue? I suspect there may be more seeing this same issue that haven't read this post.

 

[MarkZ]

Put me down as another instance of the same thing. Over the course of a month or so, the entire reservoir has emptied into the chip pan via either the x or y axis pipes/fittings.

Has anyone found a cause for this?

 

[wrmiller]

I have a different mill (PM935) but I had an issue similar to yours in that the next day after using my mill, I noticed that the oil level in the reservoir was noticeably lower. I did the simple solution and put a valve on the output of the reservoir. So now I open the valve, give the lever a pull or two (I like lots of oil on my machine's ways and screws) and then shut the valve. Now my mill is unable to siphon oil out of the reservoir.

As Mark said, you may have a worse situation where gravity is causing oil to bleed down to the ways. The valve would rectify that. Or, you could use a one-way like Mark suggested.