Date:         Tue, 3 Oct 1995 01:21:46 -0500
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         cheeses@arn.net (Cheese)
Subject:      Re: valves -> rebuild 

>Friends,
>
>It looks like I may be due for a top-end overhaul. Yikes!! A couple of
>days ago, I mentioned that the valves were *way* out of adjustment after
>only 200 miles. Bob Hoover cautiously hypothesized that there may be a
>*serious* problem with the "valve train geometry" and that I should
>retorque the heads. We're talking about a '75 type 4 engine, 1.8 liter and
>fuel-injected. Questions arise...
>
>1) do I really need to drop the engine to retorque the heads? (I've never
>dropped an engine before and the thought puts me into a mild state of
>panic.)
>
>2) If the engine must be dropped, I might as well bite the bullet and make
>somewhat sure this is the last drop for the *next* 50,000 miles. This
>engine is a rebuilt with 48,000 miles and it may be wise to replace the
>valves at this point anyway. Reworking the heads and install new valves
>will be left to a machine shop. But what other jobs would you recommend
>for the meantime? Replace clutch, piston and cylinders (or maybe just new
>rings?), increase bore (how much?),... 
>
>I'm sure all this has been discussed in the past. Feel free to refer me to
>archived contributions.
>
>Thanks!
>
>Sami ('75 Westf.)
>
>dakhlia@wuecona.wustl.edu
>http://wuecon.wustl.edu/~samid/

Sami,

You can maybe get by doing just the following, without removing the engine:

Remove the rocker arm assemblies from each head.  Check the condition of the
valve adjustment screws.  If they're battered where they touch the ends of
the valves, replace them.  Don't try to file them down smooth, as the tips
are hardened.  Using a straightedge, check to see if the tops of all the
valve springs line up.  If they do, the head probably doesn't have a dropped
seat.

You can torque the four bottom head bolts without removing the engine.
Clean, oil and reinstall the rocker arm assemblies.  Adjust the valves, with
the engine cold, of course.

Borrow or buy a compression gauge and check the compression of each
cylinder.  Ideally, all cylinders should be within ten pounds or so of one
another.  If one or more is really low, especially after you've done all the
above, you probably do need to do a top end overhaul.  If you squirt a
couple of good pumps of oil into a cylinder with a low compression reading
and the reading goes up considerably, the rings/pistons/cylinders are
probably worn.  If the reading doesn't increase much or any, the valves are
not seating well or are burned or the valve guides/seats are shot.

If you're going to all the trouble of pulling the engine, you may as well
buy a new piston/cylinder set and have the heads rebuilt, by someone who
specializes in Type 4 heads.  I recommend Mark Stephens High Performance,
805-822-5678.  I think that the cylinders on my 2.0 liter Bus are 94 mm; it
just has a longer stroke than the 1.8 liter.  This is a good chance to
replace the throw-out bearing (use a German one) and clutch disc (and maybe
the pressure plate, too).  
You might want to buy a top-end gasket set, too.  You'll probably need new
exhaust gaskets and nuts, etc.  You might consider cylinder shims to reduce
the compression ratio, so that you can run low-octane gas (saves lots of
money over the long run).  New fuel injector O-rings and new gas line
everywhere, along with a new fuel filter might help.  And, while you're at
it, it won't hurt to replace all the vacuum lines. 

I'm restoring the '79 Bus, including replacing the engine and tranny.  I
removed them as a unit, and then separated them out of the Bus.  A pair of
heavy-duty wheel ramps and a high-lift hydraulic floor jack made the job
lots easier.  The floor jack was on sale (a big, heavy, 2-1/4 ton orange
one) for $60.  The wheel ramps were about $30.

Have fun,

Cheese
'79 Bus