Shop shorthand for equipment running well above its usual temperature, checked with an infrared gun, thermal camera or a temperature sticker. Common lubrication causes are overgreasing, the wrong viscosity, low oil level, a fouled cooler and contamination. A rise of about 10 C over baseline is a common trigger to investigate, and by the Arrhenius rule of thumb every 10 C of extra heat roughly halves oil life.
Fan bearing's running hot, 88 C on the gun against 60 last week, and somebody greased it yesterday.
Also heard as
- hot bearing
- running warm
Related terms
Overgreasing
Pumping more grease into a bearing than it needs, causing churning, heat and blown seals.
Channeling
Grease pushed aside by rolling elements so it sits in shoulders beside the track instead of churning.
Viscosity
A fluid's resistance to flow, the lubricant property that sets how thick an oil film can build.
Antioxidant
Additive that slows the chemical aging of oil by intercepting the radicals and peroxides that drive oxidation.