This article is from the Chrysler-Plymouth-Dodge FAQ, by Dr. David Zatz with numerous contributions by others.
Jim Thatcher: the smoking from his 3.0 liter engine was coming
from the PCV housing. A redesigned valve cover handles the oil
properly. Details from Keith Vicker (I think): inside the front valve
cover, the PCV housing does not always drain oil properly. Drilling
holes in this MAY cure the problem - we have no experience with that.
In the older 3.0 heads the exhaust valve guides sink into the head. The
usual repair is to remove both cylinder heads, knock the guides back to
their normal position, and have snap rings installed onto the guides so
that they don't sink again. (Eric Eleazar, Dick Greenfield Dodge)
Check the oil pressure sending unit. You'll see it if you lie down and
look around the starter/oil filter area. A lot of 'em start leaking at
about 75K or so. It'll cost you around $20 to replace. Put a drip pan
under it. Then, gently back the old one out (threaded), and screw the
new one in; don't over-torque it. (Stan A. Bidlack)
Keith Vickers said: ...
Pat Goss said that in his shop only about 1 in 250 needed the heads pulled.
The seals can be replaced without pulling the heads.
DJ Allen said: My '88 3.0L was smoking like a volcano. The valve guides
were all in place. I replaced the valve guide seals while I was in there
and there hasn't been one puff of smoke since. I used Keith Vickers'
procedure. I found an 'on engine' valve spring compressor at my local
parts store for $25 and it worked, but I struggled with it because of
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