My engine was getting very hot during idle (alarm souning after awhile) I pulled the thermostat and it seemed to be pretty corroded. My friend told me that u can rmove the termostat because we live in such hot climate (caribbean) without cause damage to the engine. I did that and water still not pumping with much pressure out of the telltale. I then pulled my foot and found that the impeller was weak (all blades bent over, easy to bend e.t.c). I am going to replace the impeller, but please give info on the thermostat, safe or not thanks.