But does anyone know exactly where the door for the defrost is, because thats the one i need? But it definitely was the source of the problem. You have to take the whole box off to replace it. I have a 1983 Chevy k10 with a 350 engine. If there was no heat at all and the temp gauge was reading really low, then possibly a thermostat stuck open. It may be the water pump or the radiator.
Hello - Did you try opening the return heater hose from the core to see if any coolant was coming out? Here is a guide that can help Try disconnecting the return heater hose slightly to release any air in the core. They are small hard plastic lines wich tend to dryrot and crack easy, so be carfull not to break them when looking. Hello, I have a 88 silverado that had the same problem! You can easily see it once you pop the hood. Then you can check to see that it is operating. Now there are gremlins showing up everywhere.
If there is not good circulation through the radiator then that can cause the overheat too. Check all the vacuum lines to make sure there aren't any holes. I'd go looking for a junk yard. There is also one cable operated door, the temperature door also called the Blend Door. Install the floor air outlet duct extension.
Install the screws to the center console duct. Vacuum control motors are used to position these airflow control doors. You can reach some of the vacuum hoses and the Mode Door vacuum motor from under the dash after you remove the plastic duct that runs under the steering column from behind the ashtray to the leftmost dash outlet. I replaced everything, and when I went to replace the fan and clutch, I found out there were some motors back in 88 and 89 that were counter-rotating motors. When I shut engine off after my trip I always make sure dash display is on high heat. This is done to prevent a situation where defrost cannot be obtained due to a system vacuum leak.
Oh, and did I mention that I had to remove the lower dash to get to the mysterious box? Wow, it just started working correctly on it's own! I could then feel vacuum. On the passenger side are the temperature controls. My defrost doesn't seem to work right it just seems to blow everywhere and not very much at that either. Being they want you to be able to defrost the windshield no matter what. I've changed out my heater core and thermostat in the truck, fan blows high but no heat, checked hoses coming from core both are still cold, their is no valve, one of my hoses comes from heater core to engine the other from the heater core to the radiator, i've looked on the water pump to see if there could be a connection for that hose but their is not, any help would be appreciated, I would like to get my heater working. It me a good 8 hours to get it done finished and put back together. The valve is on the driver side, where your feet are, up in the dash on the right hand side.
I cannot get display new anymore as it is not made. You may have to check the main vacuum line coming in to the system, located under the hood next to intake. Visually check the water pump behind the pulley for signs of a coolant leak. That actuator has a blue vacuum line on it. Everything worked fine until the autostart run the battery dead and the poor truck sat with a dead battery while we were away for three weeks. Not touching anything lets it go through its relearn process. The vehicle will not overheat with a 180f thermostat in it, but did seem to before with a 195f thermostat, Do you think it could be the water pump, there's no play in the pulleys and no grinding of berrings? I put the orange line on the upper actuator, hit heat, and voila! Then shut the truck off, crank it and see if its fixed.
My truck has a crate 350 and all the smog equipment is gone, so I figure that is why. Connect the electrical connection at the mode actuator 10. I highly recommend you clean out the cowl below the windshield, as well - follow this link. This flapper door directs air either to the floor or up to the defrost. I have had 5 of them and every one had this problem until you change them out with rubber lines.
There are also some vacuum activated doors and you could check all the vacuum lines to them. The engine temp is okay. The 1l is perfect for those that are trying to finish a build and just want that Perfect firewall look. I belive that either the doors need adjusted or i Have a leak on the vacuum fo the doors, but either way i need to pull out the dash. Replace anything that is … damaged or looks to soon be a problem. We made installation so easy.