[TR] New but cheap 20 W 50 Motor oil

[Michael Porter]

On 9/21/2018 8:18 AM, Randall wrote:
> My experience (long ago) with cheap oil was that it starts producing sludge
> almost immediately.  You won't get enough in 30 minutes to hurt anything,
> but why go to all that extra effort for something that is less than
> desirable?
Ah, sludge.  Which reminds me of a short stint at a independent foreign 
car shop in the `70s.  Two regular clients were retired schoolteachers 
who had identical 1974 Honda Civics, and were in some sort of 
competition with each other.  If one had any work done, the other was in 
for work in a week or two.  If one changed gas stations, so did the 
other.  And, about the time I started at the shop, one changed to Quaker 
State oil... and so did the other about two weeks later.

These were initially pretty clean engines from casual inspection as they 
were being worked on by others, but, after a few months, the valve 
covers and valve gear were loaded with sludge.  The inevitable 
conclusion was that it was the oil.  Never made sense to me, exactly, 
until, years later, I was doing coal-cleaning research, and found, over 
time, that virtually all the coal from eastern Ohio and western 
Pennsylvania was loaded with ash that was chemically bound to the coal, 
and that we'd receive samples that were sometimes 25-30% ash content, 
but perhaps only a quarter of that could be removed physically.  It 
didn't separate from the coal until it was burned.

I suspect that Quaker State then was still using refinery feedstock from 
Pennsylvania (these were the days of peak oil, after all), and 
Pennsylvania oil was mostly in relatively shallow pools near the 
surface, with the same sort of geology as the Pennsylvania coal fields, 
and while coal and oil derive from different flora, the geological 
chemistry might well have been the same.  The oil was full of 
ash-bearing minerals, too, and when the oil gradually broke down from 
heat, the ash precipitated out.  Knowing that, the Quaker State chemists 
probably had to add quite a bit more detergent to their oil, which, as 
it broke down chemically from heat, along with the free minerals, aided 
in the formation of sludge.

So, yeah, there are cheap oils, and ash content might well be the clue 
to why they're cheap.


Cheers.

-- 


Michael Porter
Roswell, NM


Never let anyone drive you crazy when you know it's within walking 
distance....