Thanks all for the info on the drain plug... I now have a real problem!

TICK TICK TICK. Valve probs! They are loud and came on instantly. I parked
the van after coming home from work (1/2 hour trip) Had no problem. Started
it the next day to park in the garage. Ticking. hmmmmm. Started it up this
morning. Ticking. I crawled under with a screwdriver to my ear, Pass side
valve cover is really loud. You can hear it in the house over the engine
running. The other side is quiet and it's never made any noise prior to
this. I unfortunately, don't know much about the maint history of the motor.
Doesn't leak and is real clean w/ 120K miles on the van. May have had a
motor swap in the past.

So where to start? I've never worked on VW horizontal motors.

1.. I assume a lifter or pushrod. I haven't opened or verified which valve
it is. Assuming that while hand cranking the motor, I don't see anything
weird, how can I tell which one it is? Should I change all the lifters and
pushrods to be safe?
2.. Could a rocker arm have gone out of adjustment overnight?
3.. Can the lifters be removed w/o head removal? I assume not, but the
Bentley is unclear.
Can you just remove the pushrod tube w/o the head?

I've done head work on American mid-cam cars and several overhead cam cars
but never a horizontal motor. Any help on where to start would be greatly
appreciated.

Thanks, Mike
`87 Westy