Coventry(uk) Ultralite cottered bottom bracket axle has grease fittings on either end of the spindle and a hole at both bearing races so grease grease can be injected into the bottom bracket without disassembling. One could also use lightweight oil, as well.
Suntour(japan), in conjunction with Wilderness Trail Brothers(WTB), later used a similar design with their XC-Pro bottom brackets with Grease Guard. The Suntour unit has a hole in the crank arm bolts, the spindle is hollow, and their is a hole on either side of the bearing races. Injecting fresh grease ultimately purges out the old grease.
Via Bicycle 
Beats sealed bearings, thanks for posting
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