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Step belt J-head Bridgeport - upper oil cup for bull gear - oil loss system?


Cast Iron
Jul 2, 2008
Metro Detroit, MI
I always presumed that both oil cups on the side of a J-head were oil loss.
Recently I read in some head repair web page that one fills the upper oil cup until the bull gear cavity is full. On dismantling a couple of heads to access the bull gear asm I see a pair of Fafnir 208k bearings (unsealed). Should the lower bearing have an oil seal on the bottom surface or is this an oil loss system like the spindle bearings?

Related question - somewhere on some metalworking forum I seem to remember a discussion about partially filling the bull gear cavity with grease. Your thoughts?


Oct 28, 2018
Ive just replaced my bullgear bearings - they should be open bearings so the oil will run through them and lubricate the quill powerfeed gears below- any excess drips down the quill into the spindle bearings.

Some people use sealed 6208 bearings instead of the correct A/C bearings and grease
the bull gears - this is a cheap fix in my opinion

Ive changed my wick feed oil cups and made an adjustable drip feed oiler,as I dont use the mill very often. I can allow a good amount of oil to flow through before use