Date:         Thu, 15 Dec 2005 10:41:10 -0500
Reply-To:     Bill Collins <wb6otg@INTREX.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Bill Collins <wb6otg@INTREX.NET>
Subject:      Water in the oil update
Content-Type: text/plain; charset=us-ascii

My '84 is now running great and just passed emissions inspection!  Thanks for all useful information.

I learned some things that may shed some light on problems that pop up on the list from time to time:

1) Shudder when releasing the clutch:

I've heard this one blamed on many things, including bad motor mounts, a bad batch of clutches, and failing to resurface the flywheel.  In my case, I replaced the motor mounts this summer and it did not help the problem.  While the engine was out, I resurfaced the flywheel and installed a different clutch.  So far, there has been no shudder.

2) Surging idle:

This whole adventure started when the van failed emissions inspection because the idle speed would sometimes shoot up to 2000 RPM.  I've had this problem for years, but it always behaved during inspection.  Before doing the engine work, I replaced the idle stabilizer (digijet, so the it's the stabilizer box in the ignition system) and adjusted the ignition timing, idle speed, and expermented with the idle mixture adjustment.  Nothing helped.

When I had the engine out, I replaced the injector seals and just about every hose in the intake and vacuum systems, and cleaned the throttle body.  The idle still surged a bit, but was much better.
While I had things apart, I noticed that the boot between the air flow meter and the throttle body hadn't been correctly installed, and had hardened in a way that made it impossible to correctly seat on the throttle body.  I replaced the boot and the surging almost completely went away.  I then lowered the idle speed slightly and the idle became stable.

I need to raise the idle speed a bit so it will idle right after a cold start (or maybe I have a problem with the aux air regulator), but other than that, it's very well behaved.

I had previously sprayed carb cleaner on various intake parts and couldn't find any leaks.  I guess there wasn't "a leak", but a whole bunch of 20+ year old rubber parts, each leaking just a bit.

Bill