Heater problems, the slider when either all the way cold or hot makes a clicking sound and there is no heat. (1 Viewer)

[Online Olympian]

I bought this new to me 1995 fzj80 last February and there was an incredible racket from under the dash when the heater was turned on. There were 2 different sounds one clicking sound that happens when the temp slider is all the way to the cold or all the way hot. In the middle it doesn't do it. I imagine it is the blender door. I have no idea where that is located. But the other noise was a whirring sound corresponding with the fan speed. I replaced the fan wheel as it was the home to a rat and had a nest inside of it. When I did that the fan worked flawlessly and the whirring sound was gone but that was in the summer where I didn't need to use the heater. But now that it's cold out I am back to trying to heat the rig. But now I am not getting anything.
I replaced the thermostat and did a heater core flush of both front and rear. I have the heater control valve that I intend on putting in tomorrow but the rear heater isn't even putting out any heat now where before it would. Aside from the heat I need this crazy clapping sound from the blender doors to stop. I just need to know where it is and how to access it. I did have the stereo out this summer and I think the rear heat hasn't worked since. The rig has not been a daily driver but going forward it is going to have to be so I need to solve these problems.
Any help will be greatly appreciated.
Also, I have searched all over these forums for some answers. So please don't tell me to use the search function.. I have spent hours trying that.
Thanks,
Jeff

 

[shocktower]

So the flapper noise maybe the damper/blender gate ( I really don't know the real name ) there is a control wire hooked to it and this maybe disconnected, it is behind the glove box you will need to pull it out, is the fan working on the rear heater if it is not check the relay and fuse for the rear heater , also make sure all of your hoses are good , and make sure you get all the air out after you install the heater valve , I hope this helps and yes the search is challenging

 

[Desert Dino]

If the heater control valve does not function or does not open you won't get hot air from both front and rear heaters

 

[TNOverlander]

IIRC, the blend door linkage arm is visible if you lay in the passenger floor board and look up (slightly towards the center). You should see it actuate when you slide from hot to cold.

 

[MDarius]

I was just looking in the FSM and it looks like there is a heater control relay that would effect both front and rear. Is your clicking sound possibly a relay clicking?

 

[Online Olympian]

It's a loud flapping sound. But I'm willing to try anything.
No heat at all today from the front and barely any coming out the rear.

 

[Online Olympian]

I installed a new heater control valve and that did nothing to fix it. I unhooked it and left it wide open in hopes it would eventually put out some heat. To no avail. The weird part is I can still affect the flapping sound by adjusting the slider. Even while disconnected. Please help! I got an 11 month old who would like a toasty warm ride and it's in the 20s every day here in Leavenworth Washington.

 

[Online Olympian]

Went and got a Christmas tree today. It was cold..

 

[Online Olympian]

Panoramic shot of where we picked our tree

 

[Jgrauman]

Check out this thread, worked for me. Erractic Heater Temp Control Fix

 

[EvanD]

I went three winters in Colorado, Oregon, and Idaho with no heat. I didn't mind the cold but the moisture from a windshield leak made it pretty annoying. Having to scrap off the inside of the windows every morning gets old.

Anyway, in my case it ended up being because both my heater cores were clogged. Replaced the front. Never bothered with a rear as I don't even have rear seats installed at the moment.

Not sure how it would relate to the noise (that sounds like it's more related to what others have mentioned) but it's perhaps worth checking.

Edit - oops, I see now that you flushed the cores. I don't know what the process entails/if yours went properly. I just replaced it.

 

[MDarius]

No, this is definitely a mixer flap issue. It's been too long since I took mine apart to offer anything more useful. This sounds mechanical, not electrical. That slider is connected to a cable which is connected to a metal rod that is connected to a flapper that opens and closes (...this is where I get sketchy...) the goober that controls the hot/cold mixture. Find the goober.

(Thanks, "Into the Spiderverse" for the technical term "goober". There's always a goober.)

 

[Jgrauman]

No, this is definitely a mixer flap issue. It's been too long since I took mine apart to offer anything more useful. This sounds mechanical, not electrical. That slider is connected to a cable which is connected to a metal rod that is connected to a flapper that opens and closes (...this is where I get sketchy...) the goober that controls the hot/cold mixture. Find the goober.

(Thanks, "Into the Spiderverse" for the technical term "goober". There's always a goober.)

The slider is electric and moves a servo that controls the blend door. If the slider doesn't make good contact along the slide then the blend door will just click, usually extreme moves of the slide will pull it out of the stuck position, but of the solder points are cracked, it won't move at all

 

[MDarius]

The slider is electric and moves a servo that controls the blend door. If the slider doesn't make good contact along the slide then the blend door will just click, usually extreme moves of the slide will pull it out of the stuck position, but of the solder points are cracked, it won't move at all

Cool. thanks for the correction. I knew I didn't have it quite right...but he said he replaced that controller...didn't he?

 

[Jgrauman]

. He replaced the heater control valve on the firewall of the engine. This controls the flow of coolant to the heater core.

 

[Reelitchy]

Did you burp the cooling system?

 

[John Young]

Did you burp the cooling system?

How do you do that please? I'm hoping that is the problem with mine and it is bloody cold here in NOVA right now!

 

[Reelitchy]

I just park it on a hill with the front end up a foot or two (or you can jack it up) and then run it at a higher rpm for 15 min or so. Be sure to turn on the heater also to full open. that will purge all the air from the heater system. The heat should start after its purged and at operating temp. You can run around all summer and never know there is an air lock in the system but youll notice in the winter. After opening the coolant system and closing it - always check to see if you have heat.

 

[TNOverlander]

I just park it on a hill with the front end up a foot or two (or you can jack it up) and then run it at a higher rpm for 15 min or so. Be sure to turn on the heater also to full open. that will purge all the air from the heater system. The heat should start after its purged and at operating temp. You can run around all summer and never know there is an air lock in the system but youll notice in the winter. After opening the coolant system and closing it - always check to see if you have heat.

*This should be done with the radiator cap off. It goes without saying but disclaimer... do not open your cap if your car is already hot. Wait till it cools then try.

 

[musthave]

I know you replaced it, but I almost question the heater control valve still. Perhaps it could be the back side of the temperature control mechanism. That would be the second place I would look if you are 100% certain that it is not the HCV.