I need help, i got a guys 12v in the shop putting twins and other goodies on it for him, got everything put together, and now the thermostat wont open. I have tried 3 beand new cummins thermostats, i have even tested them in water out of the truck. The radiator and water pump work as they should, i ran it without a thermostat and had proper flow through everything. I have talked to a few other people at some other shops and i cant come up with anything. Please let me know if somebody has come across this, i am stumped and have nothing else to try Thanks.
I am stumped!
- Thread starter CR785
- Start date
wpeschel
Psyko
- Joined
- Aug 4, 2007
- Messages
- 872
Are you installing it backwards? That is the only thing I can think of..
Does it run hot with the thermostat in?
BrettWINspeed
Just P pump it
- Joined
- Oct 20, 2006
- Messages
- 823
Did you try a factory Cummins thermostat in it? How hot is the temp gauge showing? I've noticed that with an aftermarket thermostat in my truck and a few others that they don't open until there around 200*-210*. My originsl t-stat would open at 180*-190*.
The cooling system should have a check valve on the head with a small hose going to the t-stat housing that acts as an air bleed. You can pull the valve out of the head, fill the cooling system until the coolant starts coming out of the hole, put the check valve back in and top the coolant off. That's the easiest way that I've found to make sure there isn't an air pocket by the thermostat.
The cooling system should have a check valve on the head with a small hose going to the t-stat housing that acts as an air bleed. You can pull the valve out of the head, fill the cooling system until the coolant starts coming out of the hole, put the check valve back in and top the coolant off. That's the easiest way that I've found to make sure there isn't an air pocket by the thermostat.
Got it finally, i retraced everything like 15 times, everything checked out fine, the temp sending unit failed, it looked like it was operating properly then once the motor stated getting some heat i it, the coil must od kept getting hot and would show that the motor was running hot, swaped in a new one and things are good to go, thanks guys.