is it possible to have a dirty/clogged heater core? I don't mean the internals of the coolant plumbing, I mean the physical radiator fins that the air passes over. It seems as though when I slide the temp selector towards hot the air output decreases to almost nothing. I used to think I was crazy that this truck didn't heat up like my powerstroke until a year later when I went to use the heat out the vents and felt no air output on high. EEEEEK!

On that note, how do you also access the heater core even clean it out? I'm assuming through the cab or can I access it from under the hood? The air conditioner and cold vent settings blow sufficiently. Maybe they're plugged up too but there is a fair amount of air coming through.

Thanks,
Al

 

Yes, it is very possible to have the heater plugged. I would start by pulling the blower motor and the associated resistor pack and cleaning there. Do that from under the hood, with the motor being the round thing pointing toward the front, and the resistor pack below and to the left when looking from the front. That'll get you into the area where all the debris goes and you can determine how bad it is.

 

Thanks Gary! I know what the blower and resistor pack are I cleaned them out as there was quite a bit of pine needles. I then pulled the core cover in the cab open. I think debris is in front of the core. There is definitely more air blowing through on the cold setting.

Thanks!!!

 

Given that you've already cleaned that side once, pulling the motor might not get you to where the clog is. But, it is so easy that's where I would start.

 

To access the actual heater core, if your truck is equipped with factory A/C, remove the glove compartment door and liner and you will see the black plastic molded piece which is the backside of the heater housing. Simply remove the assorted screws and the cover will come off, revealing the core.

You will then be able to see and touch one side of the core, but to get to the opposite side, you would have to disconnect the two heater hoses and actually remove the core. Honestly, if it was mine and I did not know how long it had been since being replaced, I would consider putting in a new one [~$35-50], since the labor is already done. Just a thought!

 

They're only $50? That's not too bad. Thought they were more for some reason. I redid the entire cooling system (well radiator, hoses and water pump) last year but didn't want to get into the core. I was even thinking of having it recored just as a safety measure while I had the cover off. I think for now I'll wait money is a little tight but for $50 it might be worth it not to get stuck.

Thanks

 

and as you're playing with it, you might consider rigging up something to prevent your pine needle problem from happening again. it all comes through that panel between the hood and windshield, so a screen or something there should prevent it from happening again, or at least slow it down a lot

oh, and stop parking under that tree

 

The cowl from a later model truck has small holes instead of the slots, making it harder for junk to get into that area, and they bolt right in!