triumphs
[Top] [All Lists]

Re: [TR] oil science and break-in question

To: "triumphs@autox.team.net" <triumphs@autox.team.net>, "Fisher, Ed" <edwd@ti.com>
Subject: Re: [TR] oil science and break-in question
From: Randall <tr3driver@ca.rr.com>
Date: Fri, 8 Mar 2013 0:19:34 +0000
Authentication-results: cdptpa-omtalb.mail.rr.com smtp.user=tr3driver@ca.rr.com; auth=pass (LOGIN) a=05ChyHeVI94A:10 a=IkcTkHD0fZMA:10 a=ayC55rCoAAAA:8 a=AdqaIldLjkIA:10 a=xHsfbYGaOcNRIG9h3VsA:9 a=QEXdDO2ut3YA:10 a=_5cOzml1SGwlm8At:21 a=WTS2QP0ALHNAg6om:21 a=Bc9c7qoAuKlRg6BgnzgyhA==:117
Delivered-to: mharc@autox.team.net
Delivered-to: triumphs@autox.team.net
Sensitivity: Normal
---- "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

** triumphs@autox.team.net **

Archive: http://www.team.net/archive

<Prev in Thread] Current Thread [Next in Thread>