Date:         Thu, 30 Aug 2007 20:48:16 -0500
Reply-To:     Matt Roberds <mattroberds@COX.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Matt Roberds <mattroberds@COX.NET>
Subject:      Re: Mechanical tests for my spare air cooled engine?
Comments: cc: neil N <musomuso@GMAIL.COM>
In-Reply-To:  <20070830150826.YHOY19121.fed1rmmtai101.cox.net@fed1rmimpi05.cox.net>
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> From:    neil N <musomuso@GMAIL.COM>
> Date:    Wed, 29 Aug 2007 21:57:31 -0700
>
> 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.)

If you can do a compression test, you must have a bellhousing or the
little cast piece that lets you put a starter on it.  Depending on how
dressed up it is (does it have its FI computer+harness, or is that stuff
still in the van?) you're not too far away from being able to start and
run it.

It might be worth taking the heads off to take a look at the insides of
the cylinders, the valves and seats, etc.  If you pull a cylinder, you
can see inside the engine a little... maybe not enough to see a spun
bearing, though.

Oil analysis has been mentioned.  The small airplane people (who, by and
large, are running flat-four and flat-six air-cooled engines) often do
this, but the opinion there seems to be that it's more of a trend
monitoring thing rather than a one-shot.  One idea I've heard is that it
takes three oil changes and analyses to establish a baseline, *then*
further tests can reliably tell you if something is starting to wear at
a high rate.

Matt Roberds