The answers to the above referenced problems on my Vanagon turned out to be:

    - dipstick popping out: rubber gasket on dipstick was old and worn.
    replace with new dipstick and has not popped out since.

    - oil spray on hatch: turned out to be (drum roll) the filler tube.
    (thanks Deborah!)

Thanks to all the Volks who responded to my post.

Love and Rockets,
DaBomb

> It's me, stressing out in Los Angeles, and hoping the list can help.
> I got an engine rebuild in January on my '89 GL.  Now here's the deal:
>
> My dipstick keeps popping out.  Then, the other day after coming home off the
> the freeway I had an oil spray all over my rear hatch when I got home.  **Yet
> the dipstick was intact.**  There was an oil leak over night beneath the
> filler tube, however
>
> So, a spring was placed on the dipstick to keep it in and it seemed to solve
> the problem, although I haven't been able to drive on the freeway due to a
> running rich problem which will be taken care of on Friday, so I can't tell if
> my solution is really working.
>
> Still curious, I searched the archives and read a few possiblities as to why
> my dipstick pops out.  Such as: compression in crank case, blocked breather
> tube, etc.
>
> The reason I'm writing: I read a post which I copied  below.
>
>> Our '88 was continually losing oil also, but not leaking or burning.  I
>> discovered a stupid little detail that solved the problem.  The dipstick was
>> forcing itself out at high engine speeds. I squeezed the dipstick tube a
>> little to hold the dipstick tighter and that stopped the oil loss!!
>
>
> Putting a spring on the dip stick *apparently* solved the problem, similar to
> the solution above.  Or did it?  Are the above referenced problems possible?
> As I've said I just had an engine rebuild and am worried to death it could be
> worse than my work around solution.
>
> How do I go about determining the real cause for my dip stick popping out and
> the oil spray?  I can not seem to find a mechanic in Los Angeles who can help
> solve my current problems instead of creating new ones.  Please help me
> understand what's going on.

Love and Rockets,
DaBomb