[V8] Engine Donor

[Carol, Dave, and Zach Weiss]

Well, I get the car this coming Sunday.  It would need a _lot_ of work to
get it right to drive (timing belt, alternator, unknown hydraulic leak, two
CV boots, broken spring, 3 speakers, headliner, and some piddly stuff) but
the body is good, and it has a 4.2.

 

Had the engine checked out by a local shop w/ lots of experience and an
impeccable reputation, and they said it's ok, not great.  Owner said it
doesn't use oil, but he hasn't been driving it, and oil was 3 quarts low at
the shop-this worries me a lot.  Besides oil leaks including an oil cooler
line, they did compression and leak-down tests.  Compression is between 180
and 190 psi on all cylinders-this is good.  However, leakdown ranges from 6%
on one cylinder to 20% on the worst, and there is air going through the IM
and through the crankcase.  They said they rebuild a race engine at 10%
leakdown, but don't go into passenger cars until about 30%.

 

My 3.6 has a tired bottom end.  Runs well but uses lots of oil.  Had the
heads rebuilt a few thousand miles ago because of excessive oil consumption
and smoke on acceleration.  The shop that did the heads said compression was
good and that doing the top end would greatly improve things.  No more
smoke, but I'm using a quart every ~700 miles.  Before having the heads
done, dealer did a leakdown and said three of the cylinders had between 20
and 25% leakage with lots of air going through the crankcase, said it really
needed an engine.  Based on that experience, I'm skittish.

 

So with 217k on the 4.2, is it worth the effort, or should I look for a
better engine?  First owner had valves done at 143k.  Can I do rings on the
4.2 (obviously w/o honing the cylinders) and if so, could it provide any
benefit?

 

Dave

(now over the automotive edge, fully and truly insane)