Tri-Flow Clear Synthetic Grease forms a tough durable film of lubrication to prevent metal-on-metal wear.
It is far superior compared to petroleum and white oil based greases that are on the market today. we use this for lubing our featherweight sewing machine. It's excellent for metal gears on any sewing machine.
that which makes Tri-Flow great for gears makes it unsuitable for motors. Being a synthetic grease it doesn't get soft when it gets hot. So it won't flow to the bearings when the motor gets warm. This is lubricant for bearings, for metal gears.........do NOT use as MACHINE OIL
Remember to remove the spool pin cover-plate and bottom drip pan to grease the bottom and top gears.
Singer recommend lubricating the motor every 6 months Guaranteed to optimize the performance of your equipment's moving parts, such as bearings and tracks, and will allow them to last longer and run quieter and smoother. Prevents rusting
Remember some old Singer machines had motors that were sealed and did not need lubricant! Some 221K models had no gears.