I have a question regarding the Ford Excursion with a 6.8l. I just recently bought it used.
Here is some information in case you are curious.
Symptom: Very Low Heat, Low heat in the rear as well, Temperature gauge will not hardly go above the cold mark.
Also: Coolant was terrible so I drained it and i just went ahead and replaced the thermostat and temp sensor with it.

I have watched tons of videos on flushing and replacing the Heater core. Now my Question:
Can I flush the heater core from the hoses connected near the heater control valve rather than fight trying to remove the quick disconnects located so far back in the engine?
I think my heater core is shot but want to make sure before i progress.

Thanks Everyone!

 

Sometimes a previous owner might insert "Stop Leak" to slow down or stop a leak and it kinda clogs things up.
Heater cores are favorite places for stop leak to accumulate and you could be right about it requiring replacement.
You should be able to flush the core by way of the hoses.The closer the better..

 

Thank you that’s what I thought. I drained the radiator and didn’t see any stop leak in it which is good but when I attempted to flush the heater core it did push a tad bit of water through but also had tons of debris in it. I will pull the heater core tomorrow or so and replace it. I will post a picture if anyone is curious on what I find. What will stop leak in the heater core look like? I wasn’t leaking a drop of coolant before the drain so I’m curious.

 

Most, not all, will have a tan/brown color.

 

So interesting development. I am not sure what this will lead to but will know this weekend. I took the glove box off and attempted to remove the blend door actuator and heater core cover. The cover to the heater core won’t even budge a fraction. Removed all 7 screws and it’s like it’s glued. I may have to try to wiggle it loose with a screwdriver. I am working on the blend door as we speak. I have both screws out for it and of course it won’t budge either.

also. Can I remove the passenger side airbag and get better access to the blend door? See why it’s so stuck?

 

We usually stay away from any areas where airbag problems could develop.
Also, good move to disconnect the battery cables when working in tight quarters where bad things can happen.
Some duct work has clips to keep parts together, watch out for them.

 

So I know it’s been a while since I posted this thread but I thought I would mention what I found.
the cover to the heater core did come off with a flat head screwdriver and tons of patience! there was luckily no stop leak found in any parts of the radiator or heater core which was good!
replaced the heater core and of course all the coolant and we have great heat once again. Now all I have to do is replace the alternator