How does this happen?? Valtra 8550 thermostat

[Macsky]

Was getting engine temp spikes on a Valtra 8550, suspected thermostats needed changed, particularly the bigger one as it opens at 83°, and it would be when you were flat out on a hill that temp would climb. Sure enough big thermostat is goosed, but how does this happen?

 

[deleted user 837354]

Someone has blatted it with a hammer and forced the pin through?

 

[Macsky]

Judging by the paint in the bolts I’d have said the housing has never been open before.

 

[forblue]

The fact that it's been working and that looks a stress point, make a specific note of hour's and time and check new again when that is reached, i have seen this before only once, and not that make..

 

[Macsky]

About 7500 hours ?