Warm air mixing box thermostats

[Qldelsie]

I have tested both the 2 warm air mixing box thermostats on my car, and neither appear to be working in boiling water. But they are stamped with "140°" which, being German, I assume is 140° Centigrade, which is quite hot and might explain why they don't open at the 100° C of boiling water !!!
I will have to find a way to get them a bit hotter, I presume, although the fact that there are a few bubbles seems to infer that they are broken. What is the safest way to get them up to 140° for test purposes ?
So if I cannot find replacements, am I better to remove the mechanism and the valve and leave it all open, or am I better to leave it all in place, in which case the valve will presumably just stay closed ?
And if anyone has any spare ones that are working, please let me know - I will buy them !!
Thanks
G
BTW, I also tested my engine flap thermostat and that works OK - Obviously a lower temp setting like the 65-70° detailed by Bobnotch in a file post from 2008.

[old_man]

[Qldelsie]

Thanks Old Man - You are 100% correct. I found a friend with gas torch this afternoon, and they opened up VERY quickly !!! Very happy.
As you can see from the pic, when I opened it all up I found dead spiders and all sorts of things that had been living in there !
Am also planning to remove tha asbestos cladding and replace it with modern exhaust heat wrap or similar. If I come over to the US in 2022, I have to have an inspection to prove I have no asbestos on the car, so it is easier to take it all off now while it is in pieces instead of having to take it all apart again later !
I tested the engine thermo separately, outside of its bracket. Once the bracket and thermo is off the case, it would be kind of hard to test it in the bracket. Or am I missing something here ?
G

[old_man]

[KTPhil]

If that wrap is the same as on the large heat exchangers, it isn't asbestos.

I only know of three possible asbestos seals:
1) On a Type 1/early 2 engine, those white seals around the heat riser, embedded in the tin (lower left):

2) On a Type 3 (and maybe Types 1&2), on the rear of the large heat exchangers, the extra seal at the meeting of the sheet metal jacket and the exhaust pipe (just ahead of the main clamp/donut seal). There should be a seal and clamp at the red arrow:

You can see the proper clamp/seal here:

3) Those sealing "rings" at each connection of the large heater flex hoses under the car, usually covered by a sheet metal ring, seen here:

The inside of the accordion tubes is usually a batting type material that is cloth-based, not asbestos:

In this thread the late Russ Wolfe says the large HE wrap is definitely not asbestos:
https://www.thesamba.com/vw/forum/viewtopic.php?t=374954
It looks like identical material to that on the heater thermostat housings.

And then there is brake shoe material, but most of the is gone unless you find OEM replacement shoe linings.

[Bobnotch]

[Qldelsie]

Understand re the over extension of the engine thermostat if over heated - Good to know. However I am pretty certain that when I tested it, as soon as I saw it move, I stopped. I am sure I didn't over extend it. Same with these warm air mixing units - As soon as I saw them move, that was enough for me, and I shut the heat off.
All I can do is keep my fingers crossed. As suggested somewhere on here, I am putting a little marker on the end of the flap spindle so I can see whether the flaps are open or closed more easily in future while the engine is installed and operating. Its a good check to have, a bit like dipping the oil.
Re the asbestos issue, thanks very much for that info, KTPhil - Very useful. I will check the other gaskets / seals mentioned. Clutches, brake shoes etc I have already taken care of, and got documentation stating the non-use of asbestos from the suppliers. This is the kind of documentation I need in order to ship the car overseas and get her back into Aus after Alaska !!
Thanks all,
Giles

[Bobnotch]