Ferret thermostats adjustable?

[45jim]

I replaced the bellows thermostat in my Ferret with one from a VW aircooled van (type II) and it worked perfectly. The only challenge was the threads are metric, in hindsight one from a Chevrolet Corvair would be a better choice in that regard, I believe the Corvair one is rated at 165F. Both are widely available from many sources. My Ferret had a solid non-venting rad cap.

When bellows style thermostats wear out, the opening stroke becomes inconsistent while the opening temperature may be correct. One time it opens fully and the next it only opens 70% for no apparent reason resulting in elevated temperatures. They are designed to fail in the open position but that means fully open at 150F while at ambient temperature they will not close completely. I think the VW one costs $40.