First thing he drained out the oil (rear end) that has worked since 48, and still works. I have a 60’s model and the rear end has never been serviced. You can’t drive it hours and it doesn’t get hot. Everyone tells me it should be changed.
Maybe @morbo knows the life of like 80w gear oil from the 60’s but I don’t see any reason to service it.
Motor yes. Contaminates get into it. But closed loops I don’t see it.
Maybe @morbo knows the life of like 80w gear oil from the 60’s but I don’t see any reason to service it.
While I used to work with petrochemical engineers, I didn't find their particular engineering field was my speed. I did enjoy engineered resins and polymer engineering, but I was already doing software development for my career after leaving EE and the power industry. My knowledge of petrochemical products and their properties is weak. But, my educated guess is that 80w lubricants in a closed system would have a long lifetime if oxygen and moisture do not infiltrate the system. A heavily greased rear end that's never been cracked open probably has a long service life due to the system being mechanically simple and forgiving. A "pumpkin" from that time would be quite simplistic in that it was just a few gears rather than a modern limited-slip differential with more moving parts in it. Simplicity seems to be the key here for longevity. It's not a high precision component and that works in its favor for sure.
Pumpkins of the time were not Swiss watches. That’s for sure!
Diffs and gear boxes of the greatest quality, lubricated with the best of lubricants, always operated within spec would last a very, very long time.
All three of those stars aligning over decades? Yeah nah. I'm told changing the oil in your automatic transmission makes a hell of a difference. But I've only ever driven manual or electric.
Automatic transmissions are far different than closed systems like gear cases.
How many 100-150 year old tractors have gear oil in the belly that has never been changed?
The tolerances are of a Swiss watche, they don’t need to be. They just need to work, not mesh like a F1 car. Fuck I disassembled a windmill the other day. It hadn’t had oil in the gear cases for probably 30-40 years. All parts worked. Without issue. I turned it upside down and gear dust came out. Lots of it. More than you think. But because the White engineer on aermotor knew the conditions they would be in. The gears are heavy properly case metal. If it was just cleaned and oiled all would go back to work without fail for another 100’years. This one specifically was from 1920.