Leaking PM1236 lathe

scattermaster

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Hey guys,
So I've had my PM1236 for almost a year and I think it's the greatest thing since sliced cheese. :)
That said, I've noticed that when I clean out the chip pan and let the machine sit for a few days, there is a large puddle of oil in it.
I can't really see where it's coming from but since there is no oil in the sight glass on the carriage feed box, I assume that's the source of my leak.
The other sight glasses all show to be full.
I don't use the machine all that much and the lazy side of me says to refill and ignore it!
If I decide to try to fix it, is there a "most likely" spot I should focus on?
When I look at the exploded view in the manual it looks quite complicated. Lots of moving parts that could get lost ...
What say you?
thx,
Jim
 
The proper oil level in those aprons is below just about everything that protrudes through the casting. All the higher shafts and gears get lubricated by oil being splashed by the gears. So, I would first look at the drain plug, and the socket it screws into. It very likely is a pipe thread, so resealing it will probably fix it, IF it is the problem. You may also have porosity or a crack in the casting. The way to chase the source of the leak, without taking it apart, is to fill the reservoir to the correct level, and then clean the entire apron of all oil, totally dry. Come back and check on it at intervals, starting at 5 minute intervals, to maybe see where is coming from. It could be that it is only leaking when you run the machine, though you did say you do not use the lathe often, so perhaps not.
 
Hello Jim. Funny that you just brought this up because I had sent an email to Precision Matthews last week asking about my 10/22. I've had mine a couple of years and drained and refilled the apron shortly after I got it. Like a good boy I made sure the oil was about halfway up the sight glass. But like you, I found that every time I came to the shop there was oil on the chip tray. So Precision Matthews told me that the sight glass is actually a little too high for that lathe and it is most probably just running out of a shaft opening. Like you I've been kind of lazy and haven't really checked it but it seems to have let up and I know that all of the oil from the apron isn't in the chip tray so there's got to be a oil left in it. I should pull the sight glass on I guess and check it.
 
Ok, so I'm the shop at the moment and figured what better time to check it than now. Pulled the sight glass out and sure enough, the oil level is sitting right at the bottom of the sight glass opening. The thing that sucks is I had painted the chip tray and my stand a nice bronze hammered finish and all that oil in that chip tray seriously discolored my paint
 
guys,
The leak isn't in the apron.
The sight glass in the apron shows full.
I think the leak is in the carriage feed gearbox. That's the part on the left at the bottom.

carriage feed gearbox.PNG
 
Bob K's description is very common, and even with the proper oil level you can get some capillary wicking as there are typically no oil seals in the apron through shafts (which are above the oil level). If you look at the oil site gauge level, and some of the through shafts you will often see that they bottom of the shaft is near/at the level of the oil level. I had the same problem with my PM-1340GT, my solution was to make a small cover plate and glue it over the shaft with a a little silicone sealant which solved the weeping from that shaft. I still had some dripping from the crank through shaft and from the back of the apron. A few other sources for oil dripping down is the ball oiler from the cross slide and also when you lubricate the ways it can drip down the back side of the apron.
Oil Leeks.jpg


Shaft Patch.jpg


Edit: Ok carriage feed at the gearbox, I recall someone else with a 1236 also mentioned this, probably need a new seal. Wipe the area down, run the machine a bit and see if you can find a leak. On page 35 of the manual, see the seals 67 and 73.
 
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Sorry. Misunderstood your first post. oh well, at least I know what mine is doing.
 
My understanding is that most gear head lathes will leak some. Well, my Emco Super 11 does. I found that I had to make sure the oil was half-way up the sight glass with the lathe running. Once I did that, the leak slowed to a very tolerable level.
 
finally got around to cleaning everything up and looking for my leak. I didn't see anything but it was wet underneath the front of the gear box.
This morning I pulled the fill plug and brought the oil level up to half way in the sight glass. It didn't take very much.
I ran the machine some and couldn't find any leaks that way. It sat the rest of the day and I checked it about an hour ago, still no leaks.
Hmmm!
Well, it got me back out in the shop and that's a good thing. Been watchin too much TV.
Don't have any projects going so I decided to make a brass hammer. Got the head half way turned and came in for supper.
I was gonna buy a hammer handle and the admiral spoke up and said. " you can't say you made a hammer if you buy the handle"!
Well, I guess I'm gonna be making the handle too...
:)
 
Why would adding oil reduce leaking?
 
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