[TR] oil science and break-in question

[Randall]

---- "Fisher wrote: 
> I have a question, and I will lob it out there for any and all to answer.
> Once I have broken in my flat tappet cam with the proper break-in oil, can my
> film of lubricity then be washed away if I use modern oils after that?

Assuming you mean the microscopic film from ZDDP, then I believe the answer is yes.  As I understand it, when the film of regular oil breaks down and allows metal-to-metal contact, the film left by the ZDDP acts as a dry lubricant but eventually gets rubbed away and then grows back if there is enough ZDDP in the oil so it can be rubbed away next time.

Whether that ever happens in a stock TR motor is a different question.  I remain unconvinced, especially since I covered several hundred thousand miles with "low zinc" oil in a TR3 motor.  Unfortunately, that engine already had significant cam wear when it came to me (as shown by measured lift being low), so tearing it down wouldn't prove much of anything.

- Randall