Re: Brake-in Smokin out

[DeWitt Harrison <de@aztek.com>]

On Thu, 17 Apr 1997 11:54:19 -0400 (EDT), Scott Justusson wrote:

> [ ... ]          The summary of the article is
>that beginning with the "advancement" of oil anti wear additives, more cycles
>and cars were not bedding in their rings and pistons properly.  The
>proposition is that the older "inferior" oils allowed for some rubbing of
>parts to help properly seat reciprocating assemblies.  

Excellent post. I've been wondering about this lately as I'll be breaking
in a new head one of these days. I'm also wondering what the q-listers
who have purchased a new Audi lately are finding - or not finding -
in their owners manuals about break-in lubrication.

>Makes ya think some about the use of synthetics from the get go on a new or
>freshly rebuilt engine, car OR bike.

It does make you think. At the moment, I'm thinking maybe break-in issues
for a rebuilt head would be minor compared to breaking in rings and am
inclined to keep the synth in since the bottom end hasn't been disturbed.
Seems like the only oil consumers in the head would be valve guides
but that's not a high pressure interface. Then there are the cam journals ...
To break or not to break.  Is that the question?

Thanks,

DeWitt Harrison   de@aztek.com
Boulder, CO