My car has always stayed at a constant 175F and tonight I look down and it is almost redlining! I pulled over and felt my radiator which was COLD and the lg hose on top was warm. I opened the radiator cap and the system depressurized and warmed up the radiator to an extent. Just looking where to start, does this sound like a thermostat, even though i had some coolant movement after opening the radiator cap? Thanks for the help.

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1967 W110 200D
1977 W123 240D (RIP)

Had to replace thermostat on my '80 240 for the same thing. That is most likely suspect if your radiator wasn't dry.........

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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Since I had to leave it in a parking lot overnight (teardrop) i will just remove the thermo and see if i make it home w/o overheating, then I will know for sure. If its not asking too much, anybody know the exact tools i would need so i am prepared when i arrive to my vehicle? Thanks everyone

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1967 W110 200D
1977 W123 240D (RIP)

It is pretty much the easiest thermostat I have ever done. You will need a 3/8 ratchet with a 10mm socket. That is it!!! Don't run it long without the thermostat. These cars have a very odd circulation pattern of the water.

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

What do you mean by a "very odd circulation pattern of the water?"

__________________
1967 W110 200D
1977 W123 240D (RIP)