American Tool Works Model C lathe Tailstock pump

We have recieved a American Tool Works Model C 16x126 Lathe with the 2 speed tailstock and the Bijur pump.

I topped off the reservoir with fresh way lube to the level on the site glass. I then noticed a leak below the pump plunger area. It was weeping out of the .050, or close to that, hole dead center under the pump plunger and on the same plane as the pump mounting holes. It is too accurately located to being not meant to be so I ignored it.
Sure enough the slow leak eventualy empied the reservoir and a piddle of oil on the front way the length of the bed.

Is this a vent? Possibly the wrong pump flange that was intended for a vertical pump set up Or possibly a tattle tale for the oiling system needing attention? Similar to the weep hole in a water pump on an automobile?


Haven't had a chance to dissasemble yet.

Anyone else here experienced this

a picture of what you are talking about would be a great help. I have my pacemaker apart right now and could look to see if it's the same it at least similer

I will do on picture. Will take a few days.

It is basicaly the small Bijur T-Handle pull one shot lube pump mounted to the right of the 2 speed tailstock. It is in the front on this lathe and the site level glass is arouund the right corner facing the end of the bed. The fill hole and cap are on the top of the pump housing castin.

The small hole is just below the pump plunger shaft.

There are a lot of American lathes out there. If someone could tell me if they have a pump that works and doesn't leak out a bleed hole please look for the small hole I describe and see if yours leaks.

Thanks

I'll have a look this evening. What's the serial number on your machine ?

S/N 78734 EA 69. I understand that the 69 was the year of manufacturing. I have the photos but can't post on this computer. When I return to my computer I will put them up.

After I took the picture and looked at the assembly of the pump shaft flange it came to mind that possibly it was mounted upside down at one point by mistake. I will be back to the lathe in a few days and take it apart. If indeed it is mounted upside down and if it is possible to turn it over and remount it then the small hole would become a vent hole that would be ABOVE the fill line and not a drain hole mounted as it is.

Should be an air inlet for the plunger so it doesn't form a vacuum on the back side. Your plunger cup is split or otherwise leaking. You can probably get a cup seal from your local hydraulic seal shop or you can make a leather one from an old leather driving glove that you haven't thrown in the trash yet. Needs to be finished leather, not rawhide or suede.

Take the old cup off to use as a template. Cut a circle of the proper diameter out of the back hand side of the glove with a razor blade or punch. Punch the center hole. The unfinished side goes to the inside. Put it on the piston backwards (skin side opposite the handle end). You need to soak it in a liquid that will evaporate and leave the leather formed as a cup. I have used water if not in a hurry, laquer thinner if the machine was down. Put the piston in the tube with the leather cup (again) on backwards so it forms the cup shape. Let the cup dry and then take it back out. Turn the cup the right way and lube it with oil. Put it all back together and you're off.

I took the pump flange off today. It is mounted correctly. The pump is working great.

When I had it apart I examined the hole from the inside of the casting and it appeared to have been broken out. Imagine what a glass pane looks like on the exit side of a BB gun hole. It appeared there was some attempt to possibly punch or drill a very small hole for a rivet. I am not sure. I sealed it with silicone. Also under magnification it didn't appear to be a round hole but jagged and not round.

OK, not where I was imagining it to be. I have had this same issue in a slightly different way with the Cincy #2 horizontal at the pump shop and on my Van Norman 1-R3. I think the pump body is the dreaded corrosion loving Zamak alloy. Any moisture formed in the sump of the oiler ends up at the low point, probably forms acids and starts gnawing on the Zamak. On the Cincy and my VN, it just ate the gasket surface at the bottom edge until the gasket could no longer seal. I used the same fix... RTV.

Back together and working fine.
Thanks for the help.

I hope someday this experience will help out some one else.