I am out in the garage currently working on removal/replacement of the thermostat on our '83 300SD (my dads) and the two upper bolts broke off while loosening them...I even heated the housing forever with a torch....didn't help, even with lots of penetrant. Bottom bolt cracked free and was able to be finger loosened. Why are the upper ones so stuck??? Its crazy!! Now I have to halt everything and order new bolts from the dealer before I can even finish this.

Now I get to try removing the "stumps" from the two upper bolts with locking pliers or something....they'd better come out, I am going to heat the daylights out of them.....

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