Burned out Air Compressor tear down, what went wrong?

I picked up this old compressor in unknown condition from a friend that purchased a building with this inside, well we powered it up and it rod knocked real bad. we fixed that up by changing out the compressor head for a new one, but lets see what failed in the old one.

• #بازی_و_سرگرمی
• #mustie1
• #compressor
• #air
• #teardown
• #repair