This maybe an silly question for some of you....but. How do I know if my heater core is shot? My dump truck in sig, I'm currently plowing myself out of this storm. I'm not getting any heat and the windows in the cab are getting fogged up from my body heat. I can't see out the windows and also, its not getting hot in there. The sticky showed how to clean up the venting area but mine is not clogged up. Suggestions or comments?

Thanks

 

Is the problem no airflow or is the air out the ducts cold? Where's the temp gauge reading?

 

Check the lines going into the heater core. One should be HOT and the other should be Less Hot. If one is Cold there is an abstruction to flow through the core.

One of the lines has a valve in it to stop coolant flow through the core while in the OFF and MAX A/C settings. this valve can fail and stop flow in any position. Check both sides of the valve for heat.

 

There is air flow, it just doesn't get hot.

Temperature reading is normal.

Checking the lines...probably do this in the next warm day. Its horrible out here in N.Y. currently. But that is now on the agenda.

 

If the heater core is plugged, I disconnected my heater hoses and dribbled some CLR into one of them until it was running out the other one. Once it was running thru them I blocked one off and filled the other one up and let it sit for 10 minutes and flushed real well. Mine works as good as new again and it only took 20 minutes and 10 dollars.

 

i pulled both lines off the heater core and put light air pressure to it to blow out the crud, or corse i blew thru the return line. then i refilled with water and did it again.
hooked it all back up refilled the cooling system and it gets hot now.