How to replace thermostat

2008 Smart, oops

Welcome to SCoA. Have you looked at the Evilution site in England? They have videos and photo layouts of most of the common repairs.

Not the best video, but he hits the main points - remove the air intake, unbolt one of the alternator bolts so you can rotate it upwards, and remove any wiring plugs that may get in the way. The one bolt he points out on the long thermostat tubes has to be removed from underneath the engine. Looks like a PITA job.

Can you replace the thermostat in the housing without disconnecting the housing tubes, just in place? I see both the thermostat components and the entire housing assembly for sale.

I'm not sure. I see the replacement parts for sale but you would have to get the entire assembly out to have room to replace the internal parts - or that's the way it seems to me.