I would suspect that maybe there are also some oil pressure issues leading
to the pump being replaced. I have done head-gasket replacements on engines
of this mileage with some success. Yes, Vanagon connecting rods can and do
fail along with the cam shaft and cam bearings. But I would not just say
that at 150K a rebuild is in order unless there are some other
considerations.
Were you able to determine of the combustion leak was due to the cracked
head? If due to loose heads you may want to replace the studs. These are
almost a torque to yield and leakage at the top of the cylinders means the
studs no longer maintained enough tension to keep the heads down under
pressure.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Tom Lambas
Sent: Monday, September 06, 2010 6:35 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Should I rebuild the bottom end? Questions & photos.

My '86 Vanagon has 178k miles on the odometer.  The PO had headgaskets, oil
pump, one head (used), a couple of lifters and a rocker arm assembley
replaced. Test drive seemed fine, and I bought it. Well , it didn't take
long before I had overheating issues that I ultimately found to be exhaust
gasses blowing into the coolant.  Pulled the heads, one was junk with a
crack between the valves. I had the good head and another head rebuilt and
pressure tested. I've pulled the barrels and pistons, and I am wondering
whether to rebuild the bottom end, or not. Side play on the connecting rods
seems normal. I can't feel any play when I push/pull toward or away from the
crankshaft.  I'm also wondering if it's normal for the core to show what
looks like fine cracks on the solid area to the left of the connecting rod
(see photos).  Wrist pin wear looks minimal and the pistons look pretty
good, but I'll probably replace the pistons.

*http://tinyurl.com/39a3yso*

Thanks for any advice,

Tom