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Re: oils and flat tappet cams- - info in current issue of MGA!

To: Dan DiBiase <>, Pat Harris - sammler
Subject: Re: oils and flat tappet cams- - info in current issue of MGA!
From: Barney Gaylord <>
Date: Wed, 13 Dec 2006 10:56:44 -0600
At 04:28 AM 12/13/2006 -0800, Dan DiBiase wrote:
>I don't know of anyone that puts more mileage on his MG(A) than 
>Barney Gaylord. Here is what he says -

I appreciate the referal, and I still stand by the information 
content in that article.  But as written it has not much to do with 
recent developements under the current topic of discussion.

I have been intentionally avoiding this discussion, because it has 
the appearance of a religious war not well founded in scientific 
fact.  It is my humble opinion that oil formulations are driven by 
auto manufacturers' demands, and each successive oil formutation is 
superior to the predecessor.  When a change of oil formulation might 
be driven by environmental demands, the oil companies will find a way 
to substitute compound B in place of compound A to achieve the same 
effect, possibly at some increase of expense, but never allowing any 
reduction of oil performance.

One thing we should get from these discussions is that as of about 15 
years ago there is a different approach to lubrication of modern 
engines.  New engines are built with tighter manufacturing tolerances 
and smaller clearance gap for oil film in the bearings.  This allows 
them to use lower viscosity oil for reduced friction and (a little) 
better fuel economy.  The new cars can thrive on 5W30 oil, but you 
should never put 5W30 oil in your vintage MG engine, because the 
older bearings with larger clearances cannot survive long with very 
low viscosity oil.

Above all, you need to use the right type of oil for your vintage 
engine design.  You should by now have noted that the new oil 
furmulation that seems to have folks worried is applied to 10W30 and 
lighter grades of oil used in modern engines.  If you stick to using 
20W50 or 10W40 (and in some cases older spec 10W30), your vintage 
engine should be happy as a lark.  For a new cam and tappets follow 
long standing practice of heavily greasing the cam, or use assembly 
lube where recommended, especially if it makes you feel better.  Also 
follow proper run-in procedure with higher engine speed for 20 
minutes while you assure that the tappets do rotate.

As to the recently reported spate of cam failures, I have seen no 
scientific documentation to indicate that this is any different, 
better of worse, that it has been for the past 50 years.  It may 
simply be a matter of perception resulting from better modern 
communication spreading the stories around.  I have no personal 
concern whatsoever for the intergity of modern motor oil.  I have 
never had a premature cam failure, but then I'm stilll running the 
cam I installed six years ago (with high lift and heavy duty valve 
springs), so I cannot profess to have any experience with new cam 
run-in using very recent oil formulations.

Since I am not an expert on motor oil formulation or oil testing, my 
opinion is worth about as much as most folks, ....


Barney Gaylord
1958 MGA with an attitude

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