19 December 2014

VW Bus Valve Adjustment

This post is about the time I learned to adjust the valves on our bus.  So it is going to be a technical post that is technically for idiots.  Written by an idiot (who is trying to learn more!).  I'm a novice, take my advice at your own risk.  These instructions are applicable to a 2000 cc Type IV engine with solid lifters (fuel injected).  Kyle said that sentence, I just wrote it.  I have no idea what "solid lifters" means.
For accurate adjustment, the engine must be completely cold.  Correct adjustment is essential for maximum efficiency and minimum wear.
--Official Service Manual
1.  Remove the distributor cap - the orange guy in the photo below.  It is held on by two clips.  You can see one in the photo, the second one is on the far side.  (Access: engine compartment)
2.  Remove the cylinder head covers.  They are held on by that bar (real name: bail) in the photo below.  Push that buddy down in order to get the covers off.  Once that bar is out of the way the cover should pop off fairly easily.  (Access: under the side of the bus, behind the rear tires)
3.  Turn the engine until the distributor points to the notch.  You turn the engine by using a wrench on the alternator pulley bolt, almost shown below by the green arrow.
Here's the part of the distributor that should be doing the pointing (green arrow), and the notch it should be pointing at (blue arrow - click the photo to see it better).  I would turn it, then switch to the top engine access so that I could see the distributor from above to better observe the alignment.  Aligning these puts the #1 cylinder at "top dead center" of its compression stroke, spark plug ready to fire.
4.  Okay!  Ready to adjust cylinder #1 - the forward cylinder on the passenger side.  I needed a .006" (0.15mm) feeler gauge for the valves.  Place the feeler gauge in between the adjusting screw and the top of the valve - as shown.  There should be a moderate drag on the feeler gauge when pulling it through the gap.  Other engines use a .008" (0.20mm) gauge, so engine type matters here.
5.  If the gap is too tight or too loose, it needs to be adjusted.  Let's zoom in to see the details of how to do this.  The nut (green circle) takes a 14mm wrench and the bolt (blue circle) requires a screwdriver.
Use the wrench to loosen the nut.  Hold the nut with the wrench and use the screwdriver to either tighten the valve (clockwise) or loosen the valve (counter-clockwise) until a moderate amount of drag is felt with the feeler gauge.  Tighten the nut back up.  Check with the feeler gauge to make sure the valve is still properly adjusted.
Now that #1 is adjusted, turn the engine until the distributor has rotated 90 degrees counterclockwise, then adjust #2 (#2 is rear passenger side, #3 is forward drivers side, #4 is rear drivers side - they should be labeled on the engine, but not consistently).  Then turn the distributor 90 degrees counterclockwise, and adjust #3.  Repeat with #4.

6.  Clean up the cylinder head covers.  Who knows when the valves were last adjusted on Sixer, Kyle had to pry the old gasket out and then I cleaned up the sealing surface with the wire wheel brush buddy.
7.  Kyle, avid Samba reader, read that it is advantageous to put grease on the valve cover before putting the new gasket on to help the gasket adhere and help hold it in place.
Then install the gaskets.  Kyle purchased cork gaskets, having read that they are the superior material for this task.
8.  Reinstall the cylinder head covers.  The VW symbol should be upside down.  It's not really easy to read but click on the photo below for a better view.
When putting the bail back in place, it is helpful to add a bit of grease so that next time, it is easier to move.
9.  Reinstall the distributor cap.
10.  Start up the engine.  Listen for a clicking noise at idle.  A clicking noise means one of the valves is maladjusted.  Check for oil leaks.

We had a fairly significant oil leak after this task, which Kyle has attributed to excessive grease on the cylinder head covers. However, it is said that if your bus isn't leaking oil, you're probably out of oil.  Always travel with a spare quart or two. 

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