Sebastian gear box oil

[Shotgun]

I've had the lathe a couple weeks now, and now that I've got the chuck backplate off and 220V power ran out to it, I just had to pull the cover off the headstock gearbox. What I found has me confused, though.

The soft, pliable permatex around the top tells me that someone has been in there recently. The beautiful, factory new looking gears tells me that this thing was kept in some nice condition, or that the somebody who had it open recently did a LOT of restoration work to it. I can't see even a hint of rust anywhere, or even wear on the teeth. I did run a magnet through the bottom of it, and pulled up what might be described as black mud.

The thing that really surprised me, and I'm still at loss to explain, is the smell. Took me a minute to come to "gas station bathroom" as the name for it. One of those seedy ones on a rarely used highway exit. I first thought some moisture had gotten in, but that doesn't comport with the shiney, rust free gears. Is there a type of oil that maintains a musty smell?

 

[benmychree]

Sounds like the Mobil Vactra series. if I am reading the smellovision correctly.

 

[Martin W]

I wouldn't worry about someone else being in there before. Probably popped the cover off to have a look, just as you have. Maybe think about getting rid of the Permatex and make a paper gasket. You wouldn't want a chunck of that plugging up an oil hole
Cheers
Martin

 

[Shotgun]

Sounds like the Mobil Vactra series. if I am reading the smellovision correctly.

Sort of a low level acrid, mildewed chlorine mixed with urine type smell?

 

[FOMOGO]

Assuming it has a drain plug, just rinse it out with some diesel (may have to take out a small loan), and call it good, If all the bearings/bushings feel good. Mike

 

[Shotgun]

Assuming it has a drain plug, just rinse it out with some diesel (may have to take out a small loan), and call it good, If all the bearings/bushings feel good. Mike

I may end up doing that. But, what's there doesn't look very dirty, and if that is the way that oil smells, I'd prefer not to go through the effort, stench, mess, and expense to replace new oil.

 

[Shotgun]

I may end up doing that. But, what's there doesn't look very dirty, and if that is the way that oil smells, I'd prefer not to go through the effort, stench, mess, and expense to replace new oil.

I'd like to correct myself: The smell is more like the mildew/chemical smell of a public sauna.

Man, I think I'm thinking about this way too much. It's weird, because it just is not a normal "oil" smell.

 

[matthewsx]

Yes, change the oil. If for no other reason than you don’t know when it was changed last.

I use hydraulic “tractor oil” in the right grade and buy it by the 5 gallon bucket. Most important thing is to make sure it’s the stuff that doesn’t attack brass/bronze.

John

 

[projectnut]

If the previous owner was a member of the Sheldon Lathe board, I would bet it had 10W-30 motor oil in it. John Knox former Sheldon Design Engineer was recommending 10W-30 to replace the oil in all the Sheldon and Sebastian products. He felt it was magnitudes better than anything available when the machines were built.

I've been using 10W-30 in my Sheldon MW 56P for 7 years with no ill effects. In fact, I ran the proposal by the lubrication Engineer on our company staff before doing so. He agreed with john Knox assessment. In my case the machine usually is run 20 to 30 hours a month. There have been weeks where I've run it for over 40 hours, and others where it's set idle.

 

[woodchucker]

I've had the lathe a couple weeks now, and now that I've got the chuck backplate off and 220V power ran out to it, I just had to pull the cover off the headstock gearbox. What I found has me confused, though.

The soft, pliable permatex around the top tells me that someone has been in there recently. The beautiful, factory new looking gears tells me that this thing was kept in some nice condition, or that the somebody who had it open recently did a LOT of restoration work to it. I can't see even a hint of rust anywhere, or even wear on the teeth. I did run a magnet through the bottom of it, and pulled up what might be described as black mud.

The thing that really surprised me, and I'm still at loss to explain, is the smell. Took me a minute to come to "gas station bathroom" as the name for it. One of those seedy ones on a rarely used highway exit. I first thought some moisture had gotten in, but that doesn't comport with the shiney, rust free gears. Is there a type of oil that maintains a musty smell?

View attachment 410033

gear oil always had that smell to me. the type you put in a manual tranny or rear.