Replies

1. 
   Syracuse_Project | Jun 03, 2021 11:12am | #1

   In the past twenty years of being a Porter-Cable authorized repairman, I get asked about this a lot. Depending on the period the 503 was built ( 1952-2011), you may have a sight glass on the right side of the sander frame, or it might sport an oil cap; the sight glass was discontinued because it tended to weep gear oil if the sander sat idle for long periods.
   Long story short, all Porter-Cable worm drive sanders are filled the same way+ the gear oil should just come to the threads at the lowest oil port. Anything higher will speed up seal failure and trust me, it's no fun to dig oil/sawdust accretions out of a belt sander.

2. 
   DuluthBrian | Jan 15, 2023 01:37pm | #2

   Porter-Cable A3 Belt Sander; I have a somewhat related question and have gotten varying answers from general online searches. I am not tremendously familiar with wood working power tools. I have a Porter-Cable A3 belt sander, probably from the early 1950's inherited from my grandfather who I lived with for some years. It was one of the tools of his trade being a carpenter/cabinet maker. I use it rarely but it does seem to work fine. I think I need to lubricate it. The manual specifies Porter-Cable 33-YX worm gear lubricant and 34-YX chain case grease. Evidently neither of these is available any more. What modern product could I use for these applications; I would appreciate any simple specs, product names, etc. Thanks, Brian Guenterberg, Duluth, MN.