1993 Civic DX, 197k miles. Purchased in July 2008, with me as second
owner. In March 2009 it started burning/losing oil at about a half-
quart per 600 miles.
-- Several times over the last couple of months I have thoroughly
inspected the areas of the usual seals: dizzy o-ring, front crank and
cam seals, valve cover gasket, upper and lower spark plug tube
gaskets, oil pan gasket, rear engine seal. No leaks in these places
that I can see.
-- Replaced PCV valve a month ago. No change.
-- Coolant level is steady; no signs of a head gasket breach.
-- Runs superbly, otherwise. 42 mpg averaged over 24 tanks of gas
since March. I wonder whether the oil burning has upped the MPG a bit.
-- Inspected the spark plugs. They do not have black oil residue on
them but all four are an odd, textured color of brown and not the
usual properly combusting spark plug color.
-- Replaced valve stem seals a week ago. Still consuming oil. Thought
it might be the valve stem seals especially because driving down a
mountain using much engine braking yielded a report from buddies that
smoke was blowing out of my exhaust. One buddy said it seemed blu-ish.
Others were not sure.
-- Yesterday discovered the o-ring on the breather chamber had
permatex ultra-gray or similar on it, apparently as a temporary fix.
Also found oil residue beneath the hose connection to the breather
chamber. I cleaned the chamber up and replaced the o-ring. I
Hondabonded (I know, cheap) the grommet where the PCV valve hose
connects to the breather chamber.
1. When an oil ring or the valve guides fails, is it usual for all of
them to fail at about the same time, thus explaining why the spark
plugs are all the same color? This does not pass my common sense test,
but maybe experience is a better substitute for common sense..
2. My theory with the breather chamber is that it was running at
atmospheric pressure or so, and this may be higher than the usual
pressure, meaning the PCV valve was open more often and wider yada
than it should be. Comments?