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As I previously mentioned my truck has no problems getting warm.... a little too warm in the summer for my liking but that is not the reason for this post.
I just bought this truck in August and really had no actual reason to test the heater seeing as how it was 95° each day.
And now that cold weather is approaching I'm sure you can see where this thread is headed...
I started with the blatantly obvious things which took me to the heater valve which was stuck closed ... shown below
Which I replaced with....
I got her nice and toasty and turned the fan to the HI position for about 10 minutes.... and nothing happened. Not one ounce of heat. I double checked the valve to make sure it was open and it was.... so if I have flow what could be the no heat cause ??
Have you flushed the heater core out? Could be a blockage in the heater core or in any of the fittings that are on the block. Do the heater hoses get warm?
Have you verified that the cable is opening and closing the valve? If yes:
Disconnect both heater hose connections at the engine. Open the valve. Cob in a garden hose so that water is forced through the heater core. Pressure up.
Go from there. The above process will flush any crappy-doo from the heater core or the core may explode from the pressure if it is plugged.
Heater cores are no big deal. Widely available, cheap, easily replaced.
Matt, I agree, a control valve stuck closed is a good indicator The core could be gummed up as well. I also agree that flushing the core is a good idea. I usually like to pull both hoses at the fire wall and using a short piece of hose on one side at the time pump fresh water into the core to see if you can flush it. I will do both sides reversing the flow a couple three times to try to remove the crud. I have see some nasty stuff come out.
I do my newer vehicles as well make a big difference.
For all it's worth in effort, I may as well sprin the $40 for the new core and swap it out. Anyone have tips on pulling the old one out?
If flushing, disconnect both hoses from the engine so ya don't send the gunk and muck into the engine!
1. Strap on your patience.
2. Be methodical... bag and tag.
3. Mark the cable positions where they are clamped to the housing based how the controls are set. A silver Sharpie or blue painters tape will be your friend.
4. You may need to replace the foam strips inside the case..... they are there so the trap doors don't rattle (unlike my 68 Mustang!) and seal the chambers from each other.
I wanna make sure I understand how this works. If I have air being blown, the core heats up and the air passing through gets warm??? Seems too simple. Nothing electronic in the process other than the blower?
I have similar issues however I found the cable for the heater defrost selection has snapped
Been searching for a replacement cable and can't find it
Any one found a replacement?
Since I can manually turn the valve to on without the cable for testing I'm not really concerned about it at the moment. NPD has the cables in stock as I checked a few weeks back
So the lever on the passenger kick panel side that says vent on it should be in the on or off position? I figured off for heat you'd want it in the off poison.
Since I can manually turn the valve to on without the cable for testing I'm not really concerned about it at the moment. NPD has the cables in stock as I checked a few weeks back
Awsome! never used that site thanks for the lead....
I wanna make sure I understand how this works. If I have air being blown, the core heats up and the air passing through gets warm??? Seems too simple. Nothing electronic in the process other than the blower?
Correct.. The heater core is a heat exchanger. It works on the same principle as your radiator.
The cables control whether hot coolant enters the core and which plenum doors are open or closed.
Any 1/2" cut off plumbing valve will work. I have used manual valves where you raised the hood to turn it on in the fall and off in the spring. I have taken a 2 in piece of copper pipe and bypassed the heater core to stop hot water from getting to the core. 1/2 in pipe fits the 5/8 heater tubing.
Gary, I'd say that heater core not only looks just like a mini-radiator but is a mini radiator.
