engine break -in(was: My QR25 is dying at 15k miles :()

[spdracer@mail.utexas.edu]

> I'd think it would take forever> for your rings to seat using a synthetic
oil.

I've been reading up a lot on engine break-in recently.  It's main purpose is
to get the rings to seat in properly; synthetic oil is too slippery for that so
you must use regular oil during the break-in.  From what I've read.... At
first, you want to do light loads and vary the rpm.  Then moderate loads and
varying the rpm.  Then full throttle and up to redline.  When you decelerate,
just let your foot off of the gas as you want to create a lot of vacuum to suck
stuff out and some other reason.  Now the rampup with which you increase load
is what surprised me.  Most of the break-in stuff I read refered to motorcycles
but should still be applicable to cars.  Lots of motor break-in stuff for
airplanes too.  Anywayz, they were talking about being mostly broken in after
25 miles!  So doing around 3-5 cycles of accelerating and decelerating at the
progressively heavier loads and increasing rpms.  And you should allow adaquate
cooling between each cycle.  You also don't want to stay at a constant rpm.
Revving it up is okay, but just don't leave it at a constant rpm.  I read an
abstract from a study done at Wayne Univeristy which studied engine break-in
wear and they concluded that most of the break-in wear occurs within the first
hour.  So they suggusted changing the oil after the first hour to reduce wear
by getting rid of the metal particles.  Same deal with the motorcycle stuff I
read; change the oil after the break-in procedure(~25 miles).  Once the motor
is FULLY broken in, you can switch to synthetics.

Khiem