When reassembling any of the internal parts of an engine I’d use
something like this
rather than motor oil.
I’ve used motor oils in the past and never had any issues that I could
attribute to it. But consider what might happen while you’re
reassembling. You’ve got everything put back together and then your
kid gets sick, things get busy at your job, Aunt Judy dies, the dog
has puppies, and the neighborhood gets over run by Zulus.
By the time you’ve got things sorted out a month has gone by. And all
that oil you carefully applied to your parts has had time to slowly
drip it’s way down into the crank case.
Assembly lube stays put.
— Bob Burns via MilVinMoto