New member

[Daddy]

Hello, new member hear. First off let me say thanks for all the help I have received from this forum. I bought an old 1991 Ford explorer that had been sitting up for a while. I am not a very seasoned mechanic and this forum has helped me tremendously. So far, as a newb with no help other than this forum I have replaced the water pump, thermostat, tensioner pullies, starter solenoid, pcv valve, and heater core. I also had to reroute some vacuum lines using a diagram that was pretty much Greek to me. I am still not 100% I got the vacuum lines right. I took a pic of a white plastic, looks like a place/receptical for a vac line, but im not sure. it is on the passenger side coming out of firewall right above what i "think" is the vacuum reservior (black tube/tank shaped container that has a separate vac line coming from a check valve plugged into it. Some of these vac lines were broken/unhooked, and I just tried to the best I could to read the diagrams. Not sure how to post my picture yet. Anyhow, it's cold right now in Mississippi, and I still have no heat. Like I mentioned above, I replaced heater core, and thermostat, flushed radiator, but still no heat. The lines going to the heater core are hot, checked the core itself, it was hot. My thermometer on dash is still reading cold and never moves. Not sure if that has anything to do with it. Again, I appreciate all the help I have received already, but if there is any info one could share with me to figure out this heat deal along with vac lines please do.

 

[BrooklynBay]

Welcome to this forum! Check the blend door, thermostat, coolant level, and the heater control valve.

 

[Daddy]

BrooklynBay thanks for your response. The thermostat is brand new, coolant is topped off. I wasn't aware that a 1991 had a heater control valve, but I know that the heater core is getting really hot because I opened up the panel again and physically touched it.. The blend door, of wich I think I located the control arm to behind the glove box seems to be operating fine. I even switch the positions of the door manually by moving the metal arm connected to blend door. What is weird is that my temperature gauge is reading cold! Checked fuses for that, but all looked ok. I am curious if there is a connection between the temperature gauge and the heat, but am sure the engine is hot, and the lines to heater core, as well as the heater core are Hot. Thanks for your assistance

 

[BrooklynBay]

I think that the next generation came with a heater control valve. A low coolant level will throw off the reading of the gauge. The temperature sending unit might be defective. You could verify the temperature of the engine with an IR gun. It might be possible that the previous owner removed the thermostat or it's stuck in the open position.

 

[Daddy]

There has got to be something else blocking the air, because the coolant is flowing through and heating the core to an almost too hot to touch degree. When I flip on the AC I can see the actuator located behind glove box move (what I think is the blend door) to bypass the core. When switching off AC the actuator drops, so the air should be traveling through the core. There has got to be another blockage or something that is not working. I'm wondering if it is connected to my thermometer not reading?? Also makes me wonder about the all white plastic thingy that I spoke of in my original post. I'm wondering if there should be a vacuum line inserted into it??

Again, thanks in advance for any help as I am totally a Newb and everything I know about mechanics I learned hear since visiting here to make other previous repairs. Using this forum I have done more by myself than i would have ever thought I could, and it has actually been kinda fun. This heater deal has me bamboozled at the moment though.

 

[BrooklynBay]

You might have a problem with the vacuum lines if the vacuum servos don't switch from defrost to any other vent in the vehicle.