" wrote in message . ..
I've put a little over 100 hours on my 150 since purchase in January
'03. Recently, I've begun oil analysis with Blackstone. The universal
avg for copper on an O-200 is 9 ppm. My reading at 488 hrs on the
engine was 18 ppm and my most recent reading at the last oil change is
even higher at 25 ppm. I thought that the former 18 ppm was a
byproduct of having all of my exhaust valve guides reamed. I did this
because I was experience sticky valves. Reaming the exhaust valve
guides has cured that and it was my best guess that doing that caused
the 18 ppm reading. Now, I am getting 25 ppm in copper and there
hasn't been any service on my engine. I cut the filter open and it's
very clean. I know I'm not making metal. I'm a little worried but then
I found this link:
http://www.prime-mover.org/Engines/G...es/Copper.html

I use Aeroshell 15w50 -and- I've been using TCP additive in my fuel as
a lead scavenger. I'm no chemist but I think the TCP the article above
refers to is the same or very similar chemical as Alcor TCP which I've
been adding to my fuel. I plan to stop using the Alcor TCP and switch
to a single weight oil and see what happens. Would you be worried with
this reading? Does the article I linked to seem credible? I know it's
not recent. Also, if TCP in the oil can leach copper, wouldn't it be
able to get into the oil if used as a fuel additive?

Copper is used in various places in your engine. All the rod and main
bearings have it in their lay up. To get into the copper layer means
there is extensive wear. That will show up as lower then normal oil
pressure. The most likely source is the rocker arm bushing or the
wrist pin bushings. If ya got 18 ppm of copper in the oil you will
see it. Cutting open the filter will show larger pieces. Next time you
change oil poir a little on a whote surface in the sunlight and you
will definatly see gold sparkles in it.I assume they reamed the guides
while the ctlinders were still on the motor. If they packed a little
grease in the flutes of the reamer then most if not all the shaving
were removed during this process. I would do another analysis and see
if it is still going up. My bet it is the rocker bushing because they
had to remove them to ream the guides and if it went back together a
little dirty that would saw into the bushing a bit and give you an
elevated reading.

Ben Haas.