Ok, so I%26#039;ve been working on getting some heat in my 92 Jeep Cherokee. I tried the thermostat first, thinking for sure that was the problem. Nope. So I checked my hoses, looking for clogs and such, I notcied nasty rust colored gunk on the inside of the heater core inlet/outlets. So I figured it was bad.
I ordered a new one and busted my butt putting it in, practically taking out my entire dash assembly in the freezing cold. On the way, I checked the operation of all my vents and they seemed to work fine. So anyways, long story short, I got it in and put everything back together. Fired it up, let it run for 25. Turned on the heat...practically started blowing snow. Tried vent, same story.
What the #$%@! I%26#039;m so frustrated. Give me some ideas, what am I not thinking of? I know the water pump is pumping strong. I%26#039;m just clueless. Help!!|||there is a control valve that controls the amount of coolant that flows to the heater core. (thats how temp is controlled). make sure that it is physically opening up and that that area is not plugged. you could also have an air lock in the heater core pull the line of the outlet and ensure you have a good flow of coolant. you also dont say if the engine itself is coming up to temp, cold coolant in no heat out!. also some heater cores have backflow valves(not sure on your application) if you hook up the core backwards you will not get coolant flow(again remove hose and check for flow.|||give it a radiator flush, all that crap in the radiator well be flushed out and u will have heat|||Something in your Jeep regulates the flow,no flow, of hot water through the core...Maybe electical,manual or vacuum operated....It could be the heater control valve is bad or the vacuum , electrical or manual actuation is not working...Track it down from the heater control valve back to the actuator souce...Cruddy rust in your cooling system is caused by neglect...a chemical fush and new anti freeze/water is in order|||check flow of water though core by useing hand to see if temp is same upper and lower heater hose if is same core ok then check if heater box doors work by cotrol on dash you should have check this when repaceing core also make shure heater is bleed free or air go to rad cap loosen with engine cold or be very careful run engine with cap oiff and watch for bubbles top off rad and surge tank and let run you should have heat if not email me with engine info etc.
