There was coolant under the left rear of the engine = so I took a look.  White powdery substance on a coolant pipe.  The = coolant looked to me to be coming from the top of the expansion tank, around the = sensor.  Took it in to a shop.  The mechanic says there is a = leak on the side, where the two pieces of the tank come together, so we ordered = a new one.  Straight-forward.  The part should be in today.  = We'll get it in tomorrow.  But in the meantime the coolant warning light on = the dash has started blinking all the time--even when the engine is stone cold = .  Although the temp gauge reads normal.  I thought, ok, we're low on coolant.  Added some to the overflow with no result.  Pulled = the cap off the expansion tank, thinking it would be low--but it's full to the brim.  This I don't understand.  Could it be simply a bad sensor?  Does it sound like the coolant flow is restricted = somewhere too?  Or do I have excess pressure in the system?  I searched = the archives for the past 21 months but didn't find an answer.
 
We don't see many vanagons around here, so it's = probably impossible to find a mechanic that has a lot of experience with = them.  Therefore, I'm turning to the list before this mechanic gets too deep = into it.
 
BTW, we took the westie 2300 miles in June from = Missouri to South Carolina and back and the gauge stayed steady at just above the = warning light.  We then took it 6700 miles up to Canada, across western = Canada, then down the coast to San Diego and back to Missouri.  The gauge = ran up to 2/3 on a hot day on the interstate heading north.  Was fine in the Rockies.  But we lost a little coolant.  Discovered a leak in = a coolant pipe which was replaced in San Diego.  On some steep grades = heading to Jerome and Prescott, Arizona the needle went all the way to the top = and the fan came on momentarily, but other than that it behaved ok, so I don't = know if we have a cooling problem.  I have given some thought to a new = radiator, though. 
 
Any advice on the expansion tank leak and on keeping = cool in general would be appreciated.
 
Thanks,
Bill
'88 westie