warm heater

[rustyboltz]

This past summer I flushed the cooling system in my X. After that, I replaced the thermostat and both radiator hoses and heater hoses. During the summer the temp gauge would go up to the m and then go back down to the n and do this all over. Now that it has turned cold, My heater does not turn out very hot air, as a matter of fact, it is just warm. If the truck is warmed up and the temp gauge is on the r, I can turn the heater on to defrost and the temp will drop down before the n and stay there for quite a while. What do you think is wrong? Someone at work recommended that I flush out the heater core by its self. Should I do that?

 

[wood1]

I would check that to make sure that your vacuum actuated doors in the heater box are operating properly, and if you have one of those shut-off valves in the heater hose leading to the heater core that it is working properly too.

As far as I know the fluctuation in the temp gauge is normal and shows the thermostat is working properly by opening and closing as the temp fluctuates.

Edit: thinking now that the doors are not vacuum actuated, I think they are cable. I guess the important part is to check that your heater box is working right...

 

[Roadrunner777]

There is a outside/recirculate door that is vacuum driven, but it doesn't really matter for this concern. But, yeah, there is a cable driven blend door on the hot/cold lever.

Has it worked better before? Heater cores are cheap and not hard to replace. I'd suggest doing that rather than trying to flush the old one.

My heat takes a long time too, even with a remote start idling 20 minutes. I added a panel in front of the radiator, that helped a little bit.

I also installed an aftermarket seat heater, that helps a lot.

 

[maroon93limited]

Could have some air in the system.

 

[rustyboltz]

This will be the first winter that I will be driving the X and I have spent all my time fixing/repairing it during the past 2 years. I will be working on this this weekend. I sure hope that changing the heater core is as easy as people say.

 

[Roadrunner777]

Do you have the diverter valve on your heater hoses? It's in the engine compartment, near where the heater hoses go through the firewall. If you do, make sure it is sending good flow through to the core. If it were stuck in bypass, clogged, or otherwise screwed up, it could cause this. You could also just take the diverter out and replace it with some barbed hose couplers, and get maximum flow to the core.

The way I understand it, you can get to the core pretty easily. So check it. When the engine is warm, the core should be too.

 

[wood1]

Buddy do I have a DIY thread for you! By the mighty Glacier too...

http://www.explorerforum.com/forums/showthread.php?t=135049&highlight=heater+core+replacement

 

[rustyboltz]

This morning it is 35 deg out side and I back flushed the heater core. I cut both heater hoses and inserted a hose barb in each one and flushed out the heater core. I did that to both hoses and I did get some dirty fluid out of it along with some hard black flakes ( look like metal rust flakes). I then put it back together and ran the vehicle for approx. 40 min. I think I discovered my problem then. After 40 min. of running it, the radiator hoses are not hot. They are hot but not to the point that a person cannot hold on to them. I checked my temp gauge and it barly made it up to the second line. The block was not excessively hot either. Is it possible that my thermostat is not clossing causing the engine to not heat up? It is a brand new thermostat, 180 deg.

I checked and I do not have a shut off valve for the coolant. My heater hoses come directly from the engine to the heater core. I have looked for a vacuum line that should be hooked to it but I can not find a line that is disconnected. I have a vacuum line that is hooked to a large round long black thing mounted to the top of the air cond. housing on the fire wall. Could that be what I am looking for?

I am going to read the threads referenced and do some more checking.

 

[wood1]

Not unheard of to have a bad thermostat out of the box, unlikely but not impossible. If it is a failsafe type it should be open if failed. If it isn't open cold you can test it easily by throwing it in a pot of water and heating it up on your stove to see if it is opening properly. Obviously a thermometer that reads to 200 degrees would be helpful but not totally necessary. The water should boil shortly after the thermostat opens.

So your heater hoses are cooler than your rad hose? Sounds like "well, there's your problem".

 

[Roadrunner777]

Short story long, I have a lot of time at work to kill, and I usually spend it obsessing about my truck. I read a lot, both here and other ford truck threads. People seem to think it is worth paying extra for a genuine Motorcraft thermostat. I'm not sure why, but I went with the masses and used a Motorcraft myself. My cold blooded truck does seem to be doing a little better with it. But, of all the vehicles I have owned in Minnesota, the Explorer takes longer, maybe twice as long, to get good honest hot cabin heat.

I have added a panel behind the grill to block airflow, hoping to slow down the radiator a little bit. Heck, I drove one day all over with no fan installed, no problems. Like I said, the only solution I have found that really helped was an aftermarket seat heater, and remote starting.

I do feel your issue, I only live 5 miles from work, and I just barely get first good heat as I a park for the day.

 

[wood1]

What he said...

I too throw a black painted piece of cardboard in front of my rad for the winter.

 

[rustyboltz]

problem solved!!!! Yesterday afternooon I went to the pick-n-pull and checked the thermostats in those X's and discovered that the hole in those thhermostats have some type of floating thing in it; my thermostat just had a hole there. I bought a new thermostat with the floating metal thing in the hole and tested it and the truck works great. I now have heat and alot of it. I took it out to test drive it and it did not overheat and worked like it suspose to.

Thanks to all the people who posted here and pointed me in the right direction.

 

[wood1]

I'm thinking that you just needed a new thermostat. That small hole wouldn't have that much of an effect. Great to hear you have heat now though!

 

[Roadrunner777]

Yeah, it was a bad thermostat or you got some air out of the system. Well done!