I don't know when it first started, but the upper hydraulic assembly of
my Clausing 5914 lathe began to leak hydraulic oil, and became very
rapid over the last month, especially after I changed to thicker
hydraulic oil (which should reduce leak rate). The leakage was
restricted to the upper assembly (at the speed control wheel), and the
lower assembly (at the VS pulley on the motor) did not leak.
So, I bought a fresh set of rubber seals from Clausing for small dollars, and today rebuilt the upper assembly.
The cause of the leakage was a number of steel chips that somehow got inside the assembly. I have no idea how this could have happened - I never open the Gits oiler while operating the lathe, and I had cleaned the assembly when I last rebuilt it in 2007 or 2009, and found no chips (although the oil was a bit dirty). But there was something un-identifiable in the oil sight glass, and this had become partly dislodged. I used long tweezers to pull one bit of it out - turned out to be a steel chip. There was still something in the sight glass, so I blew it out with compressed air, and went on to blow all passages clear with air, and to wash the assembly in Naptha, and blow it out again, twice.
I replaced all the rubber; although it probably wasn't necessary, I don't want to have to take the assembly apart for a few years.
Problem solved - no leakage visible so far.
It would appear that those chips were always there, hiding in plain sight in the oil sight glass. The glass (molded clear plastic) isn't optically good enough to see that the chips were chips, but one could see that something was there.
Joe Gwinn
So, I bought a fresh set of rubber seals from Clausing for small dollars, and today rebuilt the upper assembly.
The cause of the leakage was a number of steel chips that somehow got inside the assembly. I have no idea how this could have happened - I never open the Gits oiler while operating the lathe, and I had cleaned the assembly when I last rebuilt it in 2007 or 2009, and found no chips (although the oil was a bit dirty). But there was something un-identifiable in the oil sight glass, and this had become partly dislodged. I used long tweezers to pull one bit of it out - turned out to be a steel chip. There was still something in the sight glass, so I blew it out with compressed air, and went on to blow all passages clear with air, and to wash the assembly in Naptha, and blow it out again, twice.
I replaced all the rubber; although it probably wasn't necessary, I don't want to have to take the assembly apart for a few years.
Problem solved - no leakage visible so far.
It would appear that those chips were always there, hiding in plain sight in the oil sight glass. The glass (molded clear plastic) isn't optically good enough to see that the chips were chips, but one could see that something was there.
Joe Gwinn