These tanks tend to split after about 10 years of constantly heating and
cooling, and the sensor can also loosen and leak.  Given your situation
having loaned the van to people on a trip, I would order a new tank from
one of the list vendors and have it shipped to them or to a VW shop
where they are located.  This tank is not expensive and can be replaced
without bleeding the system if the coolant lines are pinched off.

Don't take any chances.

Good luck!

Stuart

> Loretta Abbott-Kennon wrote:
>
> Hello List, I need some advice.  I just got a call from the people who
> borrowed my Syncro saying that the temp light was flashing and coolant
> was coming out of the engine compartment but the temp guage was not
> indicating that it was overheating.  I asked where the leak was coming
> from and they said it was from the indentation next to the blue cap on
> the expansion tank.  Isn't that where the temp sensor should be?  I
> gave the van a tune up and checked everything out the day before they
> took it on their trip and the sensor was there.  Do these things "pop"
> out?  I told them to stick a cork in the hole and get to the nearest
> service station and to make sure that the coolant is not leaking any
> more.  Was this good advice or have I sent my Syncro to it's death?
> TIA
> Loretta
> 87 Syncro (cripled somewhere in Nevada)
> 90  (safe at home)