The thermostat's are easy to replace and not messy at all. Just don't strip the two torx head bolts holding the upper hose goose neck on.

Drain about 2 qts of coolant from the radiator (w/reservoir cap off), then use a good quality torx head socket and evenly loosen each bolt, replace the thermostat in the EXACT same orientation with the rubber "C" gasket sliped over the circumference of the thermostat. No sealant needed. Replace the thermostat, evenly torque down the two bolts, replace the coolant, and put the cap back on. You might loose anywhere from a few drops to a tablespoon of coolant at most.

Hints :
- The drain cock for the radiator is on the passenger's side of the radiator.
- When you remove the gooseneck (with the upper radiator hose still attached) be careful not
...to overstress the upper plactic neck on the radiator. They are know to crack from stress.
- Use a Volvo OE thermostat. It's about $14 and the gasket is included. The Volvo OE thermostats
...fail OPEN, not closed.




DEWFPO
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1998 S90 071,245 and 1995 964 154,100