(T) Thermostat replacement instructions??

I see the thermostat housing (attached photo) at the end of the top radiator hose. Before I take it apart, my past experience with other cars has been that the themrostat sits inside the housing and is a simple take out old/put in new process but I can't yet see nuts to take apart the housing. When I detach from the hose clamps will this become evident or am I to replace the entire housing?? I am assuming there will be some coolant loss when removing from the hoses......do I just add replacement coolant after reassembling or does the system require flushing?
Thank you

Hi, Welcome to the FF.

Most Fiat thermostats are supplied as the complete housing. Which Spider/engine do you have?

Thanks for the welcome. Just trying to figure out how to navigate the site. I have a '81 2000 Pininfarina Spider.....was originally a Turbo but the turbo was removed when the engine was completely rebuilt a few years ago. That is fine as far as I am concerned.....seems they were always the source of issues.

And thanks for the tip about the thermostat/housing. It did seem a bit different than what I have seen before (mostly British) in that there didn't appear to be a way to lift off the top of the housing to get to the actual thermostat and I didn't want to start taking it apart until I knew I would put it back together (finished) in the same session.

Here's a few pages from the cooling system section of the Spider workshop manual. The thermostat is item #6 on page 10-161.

There's also bleeding information on page 10-160. You'll need to do this after refilling the cooling system.
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