Oil Seal Replacements

[Martin-Sy]

Hi All,
Can I pick the collective brains here on the subject of oil seals.
I'm rebuilding a 1961 CVA Toolroom lathe. Most, if not all of the oil seals encountered so far (perhaps former oil seals would be a better description) have been leather.
I've found that they have made significant grooves in the shafts that they ran on.

Here's the latest:

This is part of the belt drive input to the feed gearbox. The dismantled unit is shown below

This particular seal is 1.75" OD 1" ID and 0.37" wide.
I can find a nitrile seal for 0.93" shafts with the right OD and width and I can easily turn the shaft down but...

Am I better off with nitrile?
Will these also wear the shaft?
Can leather seals still be obtained?

Thanks
Martin.

 

[ranchero]

skim shaft fit nitrile seal, yes it will wear the shaft but it took 60 years to get that bad

 

[8ob]

May be worth looking at a double lip seal, the inner and outer may just straddle that groove. Just thoughts.

Bob

 

[Ubique]

Can you position the seal offset either side? There is/was a service instruction for some vehicle manufacturer or other that gave you three positions to fit a replacement seal on an input shaft before you had to replace the shaft due to wear. Should work OK on that if you had a different depth seal, even by +/-2mm

 

[Welderpaul]

A Speedi sleeve over the affected area would save quite a bit of work? Unlikely to get leather seals anymore unless you can find new old stock.

A double lip seal is always better than a single lip. One lip keeps the oil/grease etc inside, the other lip keeps the muck away from the area which is what will have caused the wear on the shaft.

 

[Ubique]

Never heard of those before - look like a good bit of kit.

 

[Martin-Sy]

OK Thanks everyone. I've gone for a nitrile seal and will skim the 1 inch down to 15/16 for the new seal. I'll replace the bearings (6204's ) too though they feel alright.
If it lasts another 60 years it'll be someone else's problem!
Next time I think I might try a speedi-sleeve.

The more I look at this the more odd the design seems.
What's not obvious from the pictures is that this assembly sits about 2 inches above the normal oil level in the gearbox, so it's only under pressure when the gearbox is being filled.
The left bearing is outboard of the seal so relies on grease lubrication.
When oil is added the only way it can get into the body of the gearbox is through the right bearing.
It will be interesting to see how long it takes when the time comes.

Thanks for all the replies.
Martin.