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View Full Version : Machine Maintenance - a wake-up call



Shawn Pixley
12-31-2011, 8:11 PM
I have been following the thread on rust in the neanderthal section, so I had rust on my mind. Today I spent a bit of time maintaining a vacuum pump for the local gem and mineral society. They use it for investment casting. It wasn't puling as strong a vacuum as previously.

This machine looked like it was from the fifties. In the twenty to thirty years they have had it, they had never serviced it or even known that the oil should be changed. LOML brought a few photographs but we couldn't find and brand or model identification. So it took a field trip to determine which type it was and what needed to happen.

A quick look determined that it was a piston type. Removing the oil plug, we found it was very low on lubricant and what it did have was rust colored sludge. "First thing let's change the oil." What I thought was the drain plug was actually the crankshaft bearing cover. So all the oil had to drained and refilled through and 1/8" hole. We ended up cycling (running after filled to suspend the particulates) a quart of oil through the pump before the drained oil became transparent. Afterwards we ended up being able to pull 30" of Hg.

Afterwards I came home and determined which items in the shop I need to service. Between the pump, and the thread on rust in the Neanderthal section, I got a very cheap reminder. Rust is a particular problem on the ocean and I constantly worry about the iron and steel objects. Do you guys get these epiphanies?

Jim Matthews
12-31-2011, 9:03 PM
I get epiphanies, but my Doc tells me to lay off the sweets.

Lee Schierer
01-01-2012, 3:49 PM
We had a heater unit in our church that wasn't working (the blower didn't run). I went over during the week and took the covers off to find the problem. The motor seemed fine and I couldn't get a voltage at the thermostatic switch or the motor. I took the cover off an electrical box and noticed a module with a black wire going to it and away from it. Upon closer examination and after moving the potted palm next to it I discovered an on/off switch that was in the off position. So the mystery was solved. When I turned on the power the motor and blower made a lot of noise. Upon closed examination I noted that the motor had oil cups on each end on the main shaft and it appeared that they had never been oiled. A little oil in the motor oil cups and some spray lithium grease into the blower shaft bearings and the unit was purring like a kitten with hardly any noise. After checking around no one in the church was aware that these blowers needed periodic lubrication.