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Re: Engine run-in

To: JFrymark@aol.com
Subject: Re: Engine run-in
From: "Jack W. Drews" <vinttr4@geneseo.net>
Date: Tue, 02 Apr 2002 20:40:11 -0600
JFrymark@aol.com wrote:

> I am completely rebuilding an engine that I was running on Redline synthetic
> oil. I believe a previous thread had a consensus on running in with
> non-synthetic, then switching over. Other than the cost factor of a few oil
> changes (not insignificant), any reasons not to start up on synthetic? Any
> bad experiences I hope not to repeat?
>
> John Frymark
> VARA EP #67 TR4A

I can vouch for the fact that our engines should not be run in using synthetic
oil. It cost me an engine rebuild to get the rings to seat. I had always used
dyno juice first and then switched to synthetic, but I got bad advice from an
"expert". The synthetic stuff is just too slippery. Running in and engine
involves wearing the rings and cylinder walls a little bit. My understanding of
this has been reinforced over the last winter when I finally constructed a test
stand upon which to start and check the engines I build. I run them several
times and then drain the oil. Interesting stuff to look at. No big chunks, but I
swear you can see discoloration that looks like microscopic cylinder wall wear
particles.

By the way, let's talk a little more about ring seating. I had a couple of
problems with this and was then given some advice by a guy who went to the BMW
mechanics school where he was taught how to start up overhauled engines and get
the rings to seat quickly. They put on this particular seminar because they were
having an inordinate number of failures of rings to seat. The method they teach
is to NOT put ANY oil on the cylinder walls, but to smear just a few drops on
the piston skirts. Then when you start it up you MUST run it at 2500 - 3000 for
several minutes, which we all know you should do for breaking in cams too. So
far, this has worked 100% for me and has not caused premature ring or cylinder
wall failure. I know that nearly every engine builder has a "right" way to do
it, so please don't anybody tell me how wrong I am -- at least, this one works
for me. I am  interested in other approaches that people use that work, though.


--

uncle jack

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