Weird Issue with my 74 c10 454

[vandy454]

I am having issues getting my big block up to operating temp. I am running a 180 degree thermostat and my gauge isn't reading over 160. Running an aluminum 3 row radiator and an electric fan on a 185 degree thermal switch (so my fan isn't kicking on) . from the stiffness of my upper radiator hose, I don't think my thermostat is opening. I have replaced it. Still not warming up. It also sometimes will start to steam and seep from my radiator cap area...


Any suggestions would be awesome

[blazer74]

My opinion use a 195 thermostat to start with.

[Dr_Snooz]

An infrared thermometer can help to verify exact temps.

[75gmck25]

I suggest using a 195 degree high-flow thermostat like those sold by Stewart Components .    It will get the engine up to temps, but provide lower restriction once its open.  Running a 195 degree thermostat will not cause overheating in the summer, and most engines will run more efficiently at that 195-200 degree temp.

FYI - Every thermostat is wide open at/above its set temperature.  If the engine hits 200+ degrees then all of them (160, 180, 195) are already wide open. Switching to a lower temp thermostat will not lower the engine temp if the rest of the cooling system is not adequate.  With the exception of replacing an old stuck thermostat, you can't fix overheating by going to a lower temp thermostat.

Bruce