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69-350 · 03-03-2006, 08:24 PM

one way I know my Dodge's (read: the dodge I drive, that my dad owns. god it's great being 17 and living with mom and dad :P ) thermostat is messed up is that on occassion, it will stick shut, the engine will warm the hell up (I'm talkin like 250 degrees warm) and the heater will blow cold (all the coolant is stuck, the engine warms that up, temp gauge goes up, and it gets stuck in the heater core, so the coolant in there blows off all it's heat and has no more heat to blow off)

the only other way to for sure know if your thermo's messed up is to take a pot of boiling water, and with a hook and not touching the sides of the pan, or the bottom, hold the thermostat in the boiling water and see if it opens. If not, it's bad. But that test often is a PITA and isn't worth the ten bucks to buy a new one.

Oh yeah, and if it's running hot but it's got pressure, maybe it's stuck open, and all it does is cycle the coolant through the system. This would givve you pressure in that hose, but at the same time not allow it to cool off fast enough, thus building up heat. Just my two cents.

03-03-2006, 08:24 PM	#4
69-350 Oil trash and damn proud of it Join Date: Aug 2005 Location: Williston, ND Posts: 1,993	Re: Thermostat sticking??? one way I know my Dodge's (read: the dodge I drive, that my dad owns. god it's great being 17 and living with mom and dad :P ) thermostat is messed up is that on occassion, it will stick shut, the engine will warm the hell up (I'm talkin like 250 degrees warm) and the heater will blow cold (all the coolant is stuck, the engine warms that up, temp gauge goes up, and it gets stuck in the heater core, so the coolant in there blows off all it's heat and has no more heat to blow off) the only other way to for sure know if your thermo's messed up is to take a pot of boiling water, and with a hook and not touching the sides of the pan, or the bottom, hold the thermostat in the boiling water and see if it opens. If not, it's bad. But that test often is a PITA and isn't worth the ten bucks to buy a new one. Oh yeah, and if it's running hot but it's got pressure, maybe it's stuck open, and all it does is cycle the coolant through the system. This would givve you pressure in that hose, but at the same time not allow it to cool off fast enough, thus building up heat. Just my two cents. __________________ Mark 1997 K1500 Z71, 14 bolt SF 3.73 posi, Bright Blue Metallic. 6" Superlift 1972 C-10, toolbox, p/s, 350/TH350/3.73 open, black int., bronze 2008 Dodge MegaCab. H&S tuned 6.7 Cummins. Fast Four Tons Some of my pics http://s107.photobucket.com/albums/m294/69-350/ Last edited by 69-350; 03-03-2006 at 08:27 PM.