Vacuum...Part Dos

I hadn't intended for this to turn into a series of blog posts but here we are with a second installment (See "Vacuum" for what is now part one). Its hard to predict how long its going to take before you are able to return to a project. At this point in time it has been five months since originally taking apart the vacuum pump to assess its current state, and now it looks like it took five months to figure out that the plan to get this up and going again just isn't going to happen.

So what happened? Well we weathered the "puzzle pieces" part of the project just fine. Not having any documentation to reference means taking the route of "Measure everything and start searching through catalogs for parts that match the measurements." I enjoy this type of challenge. So I set to work with a set of calipers and measured everything and pretty soon tracked down an appropriate oil seal and bearing (1 month). Coordinated with visitors to get parts here and we were set (1 month). Only to discover that while the bearing was listed as including an inner race, it in fact did not include an inner race (1 month). So back to the catalogs to track down an inner race and get it brought down with another visitor (1 month).

New bearing all pressed in there nice.

Finally we had all the parts we needed, and reassembly couldn't have gone better. Everything fit and installed well. With everything assembled the all important test had finally arrived. With the flip of a switch the motor took off, the pump was spinning nicely and drawing in its lubricating oil like it should, but there was no significant vacuum being drawn. In these instances I can't help but turn it off and back on again hoping the result will be different. In this case the results were the same. Without digging further into it I suspect the oil starvation that wiped out the bearing also damaged the vanes and glazed the pump body enough to prevent the vanes from sealing enough to draw vacuum. So at this point I don't believe its worth putting more time and effort into resurrecting this system.

Side cover installed.

All back together and looking good. (if only looking good = functioning well)

The only prior experience I have with vacuum pumps was during my time working in die casting. Those pumps were much newer than these so my experience is very limited. Someone with more experience than myself would probably have been able to assess the condition of the pump and known that it needed more than just an oil seal and bearing to function correctly again, but sometimes you just have to try it, and if it doesn't work. Find a way to keep moving forward.

I'm pretty sure this is going to turn into a three part series...

Keep after it!