Technical Thermostat question

[heggae]

I have a vintage 500 1971
It has a thermostat device under the tin on right side of engine( it was loose and fallen in when I got car ). I got the correct bold to lift it back up and attach it to the tin plate. Can anyone explain how the thing works. Seems like as I pulled it up the flap lower was closed. I tightened it snug. Does the ridgey part expand with heat and lengthen thus opening the flap to let heat escape ?? And how would I know if it’s too tight. Or if it’s working ??
Thank you.

 

[Goldnrust]

Does the ridgey part expand with heat and lengthen thus opening the flap to let heat escape ??

Exactly this

When the engine is cold, the flap is held shut, which by limiting the amount of air that can escape reduces the amount of air that the cooling fan can blow over the engine, allowing it it warm up faster.

As the engine warms up, the thermostat expands and the flap opens to allow cooling fan to blow air freely over the engine for most efficient cooling.

The bolts should be tight top and bottom, there is no adjustment designed into system. You'll know it's working when you see that the flap is closed when the engine is cold and that the flap is help open after you've got the engine hot. Like many things on the 500, its a pretty simple system, but it works fairly effectively.

 

[heggae]

Exactly this

When the engine is cold, the flap is held shut, which by limiting the amount of air that can escape reduces the amount of air that the cooling fan can blow over the engine, allowing it it warm up faster.

As the engine warms up, the thermostat expands and the flap opens to allow cooling fan to blow air freely over the engine for most efficient cooling.

The bolts should be tight top and bottom, there is no adjustment designed into system. You'll know it's working when you see that the flap is closed when the engine is cold and that the flap is help open after you've got the engine hot. Like many things on the 500, its a pretty simple system, but it works fairly effectively.

Thank you. I am not sure where to visualize the flap you talk about. But I’ll look around /under. To see if I can find

 

[Goldnrust]

The flap is directly below the thermostat, near the distributer.

 

[the hobbler]

I have a vintage 500 1971
It has a thermostat device under the tin on right side of engine( it was loose and fallen in when I got car ). I got the correct bold to lift it back up and attach it to the tin plate. Can anyone explain how the thing works. Seems like as I pulled it up the flap lower was closed. I tightened it snug. Does the ridgey part expand with heat and lengthen thus opening the flap to let heat escape ?? And how would I know if it’s too tight. Or if it’s working ??
Thank you.

Yes, the thermostat 'bellows' (the 'ridgey' part) will expand with heat and push the thermostat flap open (down). There is no adjustment in the fitting---it is on, or not on! One way of testing it is to use a hot-air gun on it---first of all blow the hot air "up its skirt" (the only way to get the hot air onto the bellows) and when (if!) it opens, blow the hot air through what should be an expanding opening above the flap. It is quite slow in operation

 

[heggae]

Yes, the thermostat 'bellows' (the 'ridgey' part) will expand with heat and push the thermostat flap open (down). There is no adjustment in the fitting---it is on, or not on! One way of testing it is to use a hot-air gun on it---first of all blow the hot air "up its skirt" (the only way to get the hot air onto the bellows) and when (if!) it opens, blow the hot air through what should be an expanding opening above the flap. It is quite slow in operation

Thank you. i took a short drive yesterday. Enough to get engine warm ( hot air out of heater ) and looked at the engine. And happily could see the flap had opened nicely.