Which Oil......

I have a 3-U universal mill, built in Spain by person or persons unknown. Tag says Zayer (still in business, but no help here). The mill is built in 1967. The vertical head is tagged ZAYFP. The overarm, however, is tagged "Cleveland". I find only images of very, very similar mills made by Ajax in UK.

I am a little puzzled by the oil that is (was) in the gearboxes. It appears to be very heavy (like 90-140) but I have no way to confirm that this is the proper lubricant. I need to refill it, but cannot find any documentation to determine the specified oil. It was a little low, so I expected it to be a little noisy, and it was, but not bad. I hate to put light oil in not knowing, but also don't want to refill it with heavy if that is not correct either.

Anyone ever heard of or seen one of these mills?

I would expect any gear oil would do, it's more like a transmission than an engine.

Well, I have a short job I need to use it on, so I may just put the standard hydraulic/gear lube (SUS 35) for the time being. If it's too light, I'll know it, and just a short run will only clean things up a bit, then I can put heavier oil in.

I would first flush out what you have. I would not want to mix oils. Is there any serious gear tooth pressure going on. Is there any obvious slop/play. Any bad noises or gear whining. Any chance of leaking oil with a lighter wt. If so to any, maybe a heavier wt oil to refill? And I would use a hydraulic oil, one that does not homogenize…Good Luck, Dave.

Dave, the job is just on Al, so the only real risk would be if I pushed the speeds up, which I will not do. The machine at this point has only normal bearing and gear sounds, nothing bad. I imagine if I don't push it, it will be fine for this job with the hyd/lube oil I have. It's what I use in the shaper and all the lathe headstocks.

And yes, I am flushing with kerosene.