Theorem- A general proposition not self-evident, but proved by a chain of reasoning; a truth established by means of accepted truths.
Hatfield's Theorem of Lubrication- 50 year old grease does not lubricate- it changes state so as advance mechanical wear between moving parts.
Ok, heck, it catches dirt and can turn quite hard! Here is a great article on how this happens.
As you can tell from previous posts, I have been working on chrome and getting ready to install door windows and quarter windows. Part of the preparation is to clean up the windows- no big deal until I actually touched the area at the base of the windows where the wheels of the winder mechanism roll. The grease seemed more like a hard varnish. This out of sight area is almost never cleaned and lubricated- that is until the winder mechanism fails and the window will not go up and down! There are parts sold to repair the damage, but the damage is avoidable. Take off your door panel and do a serious cleaning of these channels and lubricate again.
First photo in the series below show two window channels- one channel as found and the beginning of cleaning the other. The material you see in the channel was very hard and difficult to remove. Next shot shows a totally clean channel. Last photo shows this is all on original Sekurit glass.
Solution to deal with the Hatfield's Theorem of Lubrication- Get rid of all original factory grease, clean and re-lubricate!
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