99 deville still overheating

[texasplaya]

i have a 99 deville change out the motor because had a blown heads so has a new north star motor but still overheating had overhaeting problem be for thats why had to change out the motor what can be the problem.

[Godofwarmike]

possible air lock in the coolant system?

check to make sure the rad fans come on when the temp gauge gets too high.

is the rad blocked up with crap aka pollen, grass, whatever else?

did you swap the stuff from the old engine onto the new (thermostat, waterpump....) or is everything new?

if its old check or even just replace the thermostat, check to make sure the water pump is moving fluid.

im not familar with this car but is there a shroud under the rad and part of the engine? if so make sure its intact and no panels are open.

also you might have a bad coolant temp sensor.

check these and see what you come up with from there.

and also the most common problem. check the rad fluid level not just the overflow.

[Cadillakin'98]

"if its old check or even just replace the thermostat, check to make sure the water pump is moving fluid."


I sure hope you didn't put in the old thermostat. Godofwarmike is right about these being the two places to start checking. That and ensuring your radiator and fans are good. Also, remember that GM mototors are designed to run at 196 degrees, rather than 185 like most vehicles. Basically what I'm saying is that your motor will normally run a little warmer naturally.