<VV> Which OIL? Re: Doc opinion

[RoboMan91324 at aol.com]

Bob,
 
People use dino oil in a newly rebuilt engine to hasten the  break-in 
period.  It may not hasten break-in by much but this is  debatable.  Another 
reason for using dino oil during  break-in is that you will have a couple of 
very low mileage oil changes.   Notoriously frugal Corvair people hate to throw 
expensive synthetic (syn) oil  out when dino oil will do for break-in.  Of 
course, considering your  catastrophic results, throwing away low mileage 
syn oil would have been  economical if it would have saved your engine and 
allowed for a more pleasurable  vacation.
 
Regarding syn oil being used in modern engines right from the  factory, 
those engines are not our engines.  The materials and surface  finishes of 
cylinders, rings etc. on modern engines result in engines that are  essentially 
broken-in upon delivery.  Unless people on VV who are smarter  and/or more 
experienced than I tell you different, I would break-in the rebuilt  engine 
with dino oil and then switch to syn.  This assumes that you can  perform the 
break-in mileage as gently as possible.  No fully loaded  mountain climbing.
 
Your experience was the perfect storm that led to engine  failure.  The 
heaviest vehicle to normally include a Corvair engine (an air  cooled engine 
notorious for heat generation); dino oil which loses  viscosity and 
lubricating characteristics at severely elevated temperature;  an extra heavy load of 
people and vacation supplies; running the UV uphill for  an extended period. 
 Under those conditions, maybe the syn oil wouldn't  have been enough.  
Certainly, it would have helped.
 
There may have been other issues including timing.  You  may have had the 
timing adjusted well enough to avoid knock during the several  unloaded short 
trips you referenced but was it timed to prevent knock at  low speed, under 
heavy load, uphill and with elevated temperatures.  Did  you have a knock 
eliminator?  
 
Lastly, you say the damaged parts included pistons and  cylinders but you 
did not talk about anything else.  If the failure of  those parts was due to 
degraded oil, I would be very concerned about the  bearings and even valve 
guides, lifters, cam surfaces, push rods,  rockers, etc.  I know it is a PITA 
to tear your engine apart  unnecessarily but it is better than rebuilding 
the top end and discovering a  complete rebuild was necessary after 
everything is "buttoned-up" and back in the  UV.  .... and during your next vacation. 
 
You may have considered all of the above but, as always, I am  writing both 
to an individual as well as to benefit others.
 
Doc
'60 Corvette; '61 Rampside; '62 Rampside; '64 Spyder coupe,  '65 
Greenbrier; '66 Canadian Corsa turbo coupe; '67 Nova SS; '68 Camaro  ragtop
 
PS: To answer your question, I use 10W 40.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
In a message dated 5/19/2015 7:29:56 P.M. Pacific Daylight Time,  
virtualvairs-request at corvair.org writes:

Message:  1
Date: Tue, 19 May 2015 16:54:01 -0700
From: "Bob"  <bgilbert at gilberts-bc.ca>
To: <efki at verizon.net>,  <james.f.burkhard at delphi.com>,
<frankcb at aol.com>,    <corvairjack at yahoo.com>,  <virtualvairs at corvair.org>
Subject: Re: <VV> Which OIL?   Re:  Doc opinion
Message-ID:  <001701d0928f$161ad420$42507c60$@gilberts-bc.ca>
Content-Type:  text/plain;    charset="UTF-8"

Hi.

Now this is both  interesting and timely. I am one of those under the 
impression that you needed  conventional oil for the first few hundred miles.

Are we now saying  that I can put synthetic in a freshly built engine like 
the 3.1 I am putting  together for my UltraVan?

If so, what  weight?

Thanks,

Bob