No Heat
#11
Linden, NJ here
#12
Remove your heater hoses & reverse flush out the heater core. I literally just did this yesterday! I had calcium deposits in my heater core from the previous owner using more water vs coolant. 230K on my D2 so no biggie. I bought 5ft of 5/8 heater hose, cut off the old heater hoses taking care not to tug on the heater core lines (you DO NOT want to damage the heater core lines/O-Rings). Flushed out the heater core backwards to push the crap out vs thru it, removed the 8mm bolt securing the second heater metal line to the other, carefully rotated it out of the way, cleaned off the metal line ends, slid the 5/8 line on it with a little WD40 to make it slid on easier, then I cut to fit the line. I did not put the heater core lines back into their OEM criss cross pattern. I went with the RRC setup straight in/out. Once done with the inner line rotate the outer lane back into position, and re-install the 8mm bolt, then slid the outer 5/8 hose on, and cut to fit as well. Secure them up with new hose clamps, and boom you’re done.When flushing the core I’d run it backwards at first and let it flow until it’s good and clear then flush the other way for good measure. After that run the D2 and check for any leaks, you should start getting heat, and the in/out hoses will be warm (I checked mine before I did any work and only one was warm. The other line was stone cold). Also for maximum heat make sure ECON mode is selected so the AC compressor doesn’t run. While my heater core was clogged I had zero cooling issues, just zero heat.
#13
Just came across this post. Is there also a possibility that the heater core is not clogged and still blowing cold air? Somehow, 3 days ago, I observed that there was no heat and very cold air blowing but when I turned the temperature setting on/off, it started to work fine again with hot air blowing. Could there be a sensor not functioning or just the air control switch combined with the temperature? Cheers!
That sounds more like a blend door motor flap inside the HVAC unit itself not opening to allow warm air into the cabin. I verified my issue by feeling the heater hoses themselves. They’ll both be warm if it’s not clogged. If one is hot & one is cold it’s clogged.
#14
Thanks, I'll see if the condition shows up again and start checking it.
#15
#16
Touching a heater hose takes 2 seconds. I have never had any issues with trapped air in the heater core. It “should” purge upon shutdown, “if” you are getting air into the heater core you have a leak somewhere & the most common seepy bit = Throttle Body Heater Plate, or from the top of the radiator where the two phillips head screws go that hold the lower fan shroud in place. Remove the plug in the T and top off & after a few hot/cold cycles it “should” be free of any air. I’ve never had to park a LR on a hill to get the coolant system free of air.
#17
Here I have to agree with Best4x4. I have 3 discos to date and owned my 1st disco for 14 years and still my daily driver and not even once I touched the bleeder. Only few occasions I can tell when I heard bubbles in the heater core and I can be definite with these ones I experienced. 1) coolant low and reservoir almost empty due to leak 2) head gasket failure and 3) cracked block.
Years I dont have a bleeder and its copper and no issues at all.
Cheers!
Years I dont have a bleeder and its copper and no issues at all.
Cheers!
#18
Yeah I've been trying to find a copper T just to eliminate the possibility of a failure from the bleeder flying out (I've seen it happen several times on/off road).
I bought one I thought was going to work, but I couldn't get the new coolant hoses over it, and just went back to the OEM T.
I bought one I thought was going to work, but I couldn't get the new coolant hoses over it, and just went back to the OEM T.
#19
Someone posted this a few weeks ago. Looks like a great upgrade. Scroll halfway down the page...
V8 Chevrolet TPI & TBI, Radiator Hose Tees, Stealth Conversions
V8 Chevrolet TPI & TBI, Radiator Hose Tees, Stealth Conversions