most timing belt engines can be turned backwards too.
for sure, on a Benz diesel only turn forward.
on a waterboxer, there's not timing chain or belt tensoner, or mechanical
injection pump to damage or anything.

turning a VW oppossed four  engine backwards for convenience, say for
adjusting valves, , so the order is 1, 2, 3, 4, ..............that goes back
to the 60's at least.......I probably learned that in the Idiot's Guide for
air cooled VW engines.

it's also REAL handy for checking the firing order of the plug wires on the
distributor cap.  You just mark or know where # 1 is,,,,,and going
counterclockwise count 1, 2, 3, 4.
how nice !

----- Original Message -----
From: "Allan Streib" <streib@cs.indiana.edu>
To: "Scott Daniel - Turbovans" <scottdaniel@TURBOVANS.COM>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, August 13, 2008 5:39 PM
Subject: Re: Hydraulic valve adjustment question

> Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM> writes:
>
>> I adjust the valves with the rotor pointing to that cyclinder.
>> conveniently, if you turn the engine backswards it's 1, 2, 3. 4
>>
>> I thought it was 1.5 turns after contact.
>
> I guess that's one advantage of a car with a gear-driven (not belt or
> chain) camshaft -- you can turn the motor backwards??
>
> It's absolutely verboten on a Mercedes engine, for example.
>
> Allan
> --
> 1991 Vanagon GL