I agree with Kerry. The Thermostat is probably not bad. these things usually fail OPEN and not closed... On a Diesel it will overheat quickly if there is no pressure in the cooling system. The loose hose probably lost enough coolant and prevented it from pressurizing and it ran hot.

They are fairly forgiving if you don't run them long or way up in the red...

I'm not familiar with the air bubble theory in refilling the water. I always fill it, run it till it is warm, cool it down and top it off.

Chronic overheating can be serious. A bad head gasket or a crack but that is not too common. Even a seeping water pump on a diesel will cause overheating... anything to lose water and keep it from pressurizing.

Hope all this helps!

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92 500SL
92 400E (Sold)
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