ML7 backgear lever lubrication.

Hi all,The oil nipple on the backgear lever shaft is not linked to the tiny hole in the main body? So how does this get its oil? Or am I missing something?

Photo

I have just been to study mine, and I must admit I am not sure what you mean.

There are oil-nipples for the countershaft journals themselves, which do need regular lubrication.

None though for the lever shaft and the frame journals. Not on my example anyway. These are not fast-moving parts in full-time use, and mine seem perfectly happy with a spot of oil on their various facings so it can wick itself into their journals.

Bootleg,

It may well be that grease has been used in the past. I had this problem which led to seizing the bearing.

Remove the oil nipple and clean the bore thoroughly, then assemble and test with your oil gun to check that oil is getting through before reassembly. If you have a mill it may pay you to run a shallow groove along within the pin length to distribute the oil over the length of the bearing.

Regards Brian

I’ve had wires and cleaning fluid and an airline in all the holes,yet cannot find a connection between the nipple and hole shown in the picture?

Is there one on the fat end?

Leave it to soak in a container of solvent for a few days. Must be plugged up hard with gunge. (To use the technical term.)

You could also try putting a grease nipple in place of the oil nipple and hook up a grease gun and pump it hard. They will develop a pressure of some 2,000 psi and more and shift things that 100 psi of air will not. Clean out the new grease afterwards and revert to the original nipple and oil.

Definitely no link between oil nipple and hole ,So should there be ? I could drill an oilway to suit from the small end past the nipple to the hole, any thoughts ?

It may be that your unit is a later design change. I say later, as the one I have is from my 1949 ML7 and the protruding backgear spindle (1/2" dia) passes all the way through the body and locked with a grub screw underneath at the lever end.

If your spindle is set into a blind hole of the unit?, then the small hole may be there for relieving the pressure when it was pressed in.

I would not drill any holes for lubrication, as it is possible it is supplied from the front main spindle bearing above it?.

You can also just add a few drops to the joint/mating face on the inside of the headstock next to the oil nipple and that will be drawn in by capillery action as mentioned previously.

Never heard of a seized up eccentric back gear unit, so it must be ok for a light oil when fitting it.

Regards

So,, where does the oil come out when you squirt some in the oil nipple? I would have thought it should come out somewhere on the smaller diameter section where the back gear actually runs.

Seems like you would not need oil gun lubrication on the fat section that runs through the headstock casting and only gets moved a quarter of a turn or less at a time to engage or disengage back gear. But, so long since I had mine apart I dont remember exactly where it goes.

Edit: Looking at a few pics on the net it looks like perhaps there is a small hole in the centre of the fat part, right at the root of the smaller diameter spigot, where oil would come out and lubricate the spinning gear, sort of. If oil comes out there when you squirt it in the nipple, I would not worry about the other hole. It might even just be an indexing hole for manufacturing purposes. But certainly not a necessity to lubricate the quarter turn of movement. A few drops of oil in the general area once a year should tdo that.

Edited By Hopper on 12/08/2022 11:22:06

I only have an image of the old version, as I replaced mine back in '86'. I now have the same type fitted as the OP's unit. The original unit breaks down to this-

Note this type did not have an oil nipple, just a countersunk hole for oiling. Hopefully you can see and relate to all the relevent holes in the one image.

Another reason not to drill a hole through the backgear spindle is that it is likely to be hardened and tempered for the backgear to run on.

Regards

I’m with you on this one Richard S2. A blind hole vent sounds like a good answer,So I’ll leave well alone and just oil prior to fitting.Thanks to all.

So, where does the oil come out when you pump some into the nipple?

So,, where does the oil come out when you squirt some in the oil nipple? I would have thought it should come out somewhere on the smaller diameter section where the back gear actually runs ?

yes it does. Thanks Hopper.

Ah, in that case then, lubrication is all good. No need to worry about that unconnected hole in the larger diameter. It may possibly be an indexing hole from the manufacturing process and never was meant to connect with any other hole.