You have a problem besides just a leak.

I also have an 88 GL vanagon and had the very same problem. Right after
I bought it, I had this very problem.

It was found that when coolant pressure was applied  to the sensor with
sufficient force to blow it out of the expansion tank, the threads of
the sensor and the coolant tank were damaged, and both required
replacement. The problem was caused by two things..........faulty
thermostat, and faulty pressure relief cap. Replaced both, replaced the
expansion tank, and the sensor, and the problem was solved.

There are other possibilities, but the most likely scenario is the one
above.

One other thing.... and this doesn't bear on the sensor blowing out
however....and that is be sure and keep your coolant at a 50/50 mix
ratio colant to water on the WBX engine.

Hope this helps.

Regards,

John Rodgers
88 GL Driver

Catherine,John Russ wrote:

>I have a 88 vanagon with a leaking coolant level sensor. I have a new sensor and expansion tank put back and it is still leaking . And it even at one time it pop out of the tank. OK what is the secret on how to fix this.
>
>
>John R
>1988 Vanagon
>Gloucester MA
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>