Oil Analysis.
If there's excessive bearing metal, or piston or ring metal or whatever,
it'll show up in the report from the oil lab. 

Otherwise, either remove and inspect the rod bearings.... which can turn
into doing new bearing and rings etc. 
Or run the engine. 

On various waterboxer engines .... I've  tested for the valves not sealing
well by filling the intake & exhaust ports ( relative valve fully closed )
with gasoline , or paint thinner, or kerosene  - some petro thin juice like
that.....found 2 out of 4 exhaust valves leaking on a couple of engines that
way.    

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
neil N
Sent: Wednesday, August 29, 2007 9:58 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Mechanical tests for my spare air cooled engine?

Hi all.

Aside from a compression test, measuring end play, (and of course
installing and running!) are there ways to tell if there's anything
totally wrong with a given 2.0 air cooled engine? (like spun bearing
etc.)

I have a spare engine that I've harvested external parts from, but
have no idea if it's mechanically sound or not.

Just curious,

Neil.

--
Neil Nicholson. 1981 Air Cooled Westfalia -
"Jaco"  (Bustorius)

http://web.mac.com/tubaneil

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