Thanks
I took a look in the Bentley and My Glove box. ( I knew I had a
sending switch in there but did not know temps)
I looked at it and it is OEM VW Audi.
Part number is 251-959-481K
The numbers on the side is 87/76 and 93/82
Not 100% on the numbers but it sounds like it will work fine.
Let me know if I am wrong or not.

Jonce

>AFAIK, Bostig programs the ECU to go into a low power limp mode when
>the cylinder head temp gets too hot. That may be what is happening to you.
>
>There are lower temp radiator switches you can install. The stock
>2.1 rad temp switch is what I would recommend. The original 1.9
>switch lets the rad get too hot. There is an even colder one
>available but in warm climates it makes the fan run a heck of a lot
>and is annoying at the least. Us only Wahler or Behr brand temp switches!
>
>Also it is simple to wire a manual switch to trigger high speed fan.
>However the 85 and older fuse box wiring is not really strong enough
>to support too much high speed operation of the radiator fan. Warning....
>
>Mark
>
>
>Jonce Fancher wrote:
>>Hi all
>>Just got back from a 2 Week Balls out drive outwest to 4 corners from
>>Michigan in the 85 Vanagon.
>>
>>Had a few issues in the HEAT of Texas and OK.
>>
>>The Rad Fan did not click on to it's HIGH speed. It did on the 1st
>>speed but not the 2nd.
>>
>>The Motor cut off ( Sorry it is a Zetec Bostig Conversion. 1st group
>>Conversion )
>>
>>Seems the Brain located above the muffler ( heat shield in place )
>>Seems the cut off over heat protection sensor on the motor cuts off
>>before the high speed on the fan kicks in, ( I THINK ).
>>Temps outside were about 102 to 106. It acted like the fuel pump was
>>over heating as well. Anyone ever have the Fuel Pump over heat.
>>I went ahead and swapped the fuel pump with my back up. ( which
>>didn't work. ( Love new stuff that does not work.)). Had to go into
>>town and find one. Swapped it and the issue continued. We wrapped the
>>Brain in heat shield and it seemed to make it a bit better but still
>>did it once or twice.
>>
>>Need to check the Fan and the sensor. Can I put a switch in to bypass
>>the Thermal switch OR is there a different switch with different temp
>>settings??
>>I have no problem with a relay and switch install to control over heat.
>>I thought of installing a 2nd oil cooler ( which I have one on the
>>shelf with Fan ) But I think the extreme of the issue is the Brain is
>>located in the engine bay and the heat outside was HOT! But I do feel
>>the brain is cooking.
>>
>>Few other issues on the trip but mainly good fun.
>>
>>Jonce