My wife’s 02 crv won’t put out heat. It has 1yr old water pump and thermostat. Have blown out heater core and ran cleaner threw it. Temp only gets to just below half on gauge. Top radiator hose gets to 140 bottom hose only 65, input heater core hose is 140 output is only 65. Do I need to replace the thermostat and heater core? Any ideas would be helpful!!

 

Your numbers don't make sense. The top should be much higher and to be dropping 75 degrees through the radiator is astounding.

 

I agree, I was using a temp gun on the hoses and it didn’t make any sense to me either. Once I let it warm up for 30 mins the bottom hose changed to 84f, which is a lot closer and my fans were kicking on but the top hose only ran 144f.

 

The temps you got from your gun do not reflect actual coolant temps however they may provide some clues.
To further validate my hypothesis it would be good if you would provide the ambient air temp at the time of the test and the temp rating of the thermostat you installed. I’m guessing it is not 140*.