I saw this on the motorcycle modifiers mail list so I thought I'd
pass it along. How to break in an engine down under :-0
Ben Bennett
-------- Original Message --------
Subject: RE: Running-in + oil
Date: Tue, 7 Mar 2000 20:43:05 +0800
From: "Kelvin Blair" <nwk@bigpond.com>
Reply-To: mcmod@research.canon.com.au
To: <mcmod@research.canon.com.au>
Hello McModers
I can't sit back any longer on this thread.
My experience and/or opinion is thus.
It is a complete fallacy that you should not run a motor in on
synthetic
oil. The only reason for not doing it, and it is a very good
reason, is
that it is expensive!
The most important part of running in a new or rebuilt engine is
to get
pressure on the rings to seat them adequately in the bore.
I will explain this with an example of a 2H diesel engine I
rebuilt
recently.
Rings were put in dry!
A smear of oil on the piston skirts.
Engine completely assembled and fitted into landcruiser.
Vehicle was towed to a rest bay on side of highway.
The engine was not turned over uneccessarilarly at all.
Engine was started, and this is where a lot of engines start there
trouble
from, you must have every thing right so it starts straight away.
Continuous cranking of an engine to attempt starting on new rings
is
disastrous.
Engine was run to check oil pressure etc and bring to temperature
and then
shut down.
Now this is where most people will lose it.
A ten ton truck was hooked up by tow rope to the landcruiser. The
engine
started and then off down the road we went.
Why?
Cylinder pressure. The truck had its motor running for its brakes
and he
held me back on the RPM so I could have wide open throttle.
We did this for 50km stopped, checked everything out, then went
back again.
Slowly bringing RPM up.
Run in procedure complete.
Drop oil. Give to wife to drive. Drop oil again 500km. Fill with
Red Line
Synthetic. Has just done 14,000km on this oil, has not used a
drop, dose not
smoke. Runs like a charm. I send a lot of oil samples to labs for
analysis
monthly for gas turbines so occasionally I slip in the 2H
synthetic oil.
The engine is fine.
You must get those rings to bed in straight away. Any ring
manufacturer
will tell you this.
The only way to do this is cylinder pressure, wide open throttle,
the only
issue here is RPM, difficult to limit if you are not on a dyno or
don't
happen to have a ten ton truck to tow around on outback roads.
Cheers
Kelvin
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