1991 FJ80 Front heater lukewarm, rear heater hot
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Mine is the same way and my cooling system had rust in it. Clogged?
Yeah, pull your heater core. It sucks but you'll see why when you do. Clean it. Careful not to damage the fins. Don't use anything corrosive.
Mine was virtually a solid sheet of leaves, dirt, and other gunk. It was disgusting. I blew it out with an air hose from the back. Then garden hose. Then soaked it in the sink overnight. Then LIGHTLY brushed it with a toothbrush.
Mine was virtually a solid sheet of leaves, dirt, and other gunk. It was disgusting. I blew it out with an air hose from the back. Then garden hose. Then soaked it in the sink overnight. Then LIGHTLY brushed it with a toothbrush.
- Thread starter
- #6
Looks like this provides good info for how to flush the heater core.
Heater Core Flushing - OWNED!
I don't think it's air bubbles because what little heat does come through the front vent is pretty consisent. It sounds like if it's inconsistent it's air. Please correct me if I'm wrong here...
Heater Core Flushing - OWNED!
I don't think it's air bubbles because what little heat does come through the front vent is pretty consisent. It sounds like if it's inconsistent it's air. Please correct me if I'm wrong here...
- Thread starter
- #7
C
Cancel my last. I feel way better about just pulling it and giving it a good clean. I'm way too scared of flushing something bad into my otherwise (probably) good cooling system.
Cancel my last. I feel way better about just pulling it and giving it a good clean. I'm way too scared of flushing something bad into my otherwise (probably) good cooling system.
I have never seen that thread before. That looks pretty cool to me.
Helluva lot less work then what I did. That's for sure!
The process I explained was what I did on my 92. If/when my 93 starts to show NEED I will try this.
Just remember that the coolant you use should be what you already have in there. Don't mix red and green.
Helluva lot less work then what I did. That's for sure!
The process I explained was what I did on my 92. If/when my 93 starts to show NEED I will try this.
Just remember that the coolant you use should be what you already have in there. Don't mix red and green.
I don't. Not home so don't have it in front of me...
Might want to check your heater control valve too. That is the U shaped thing on the firewall above the motor. Make sure that it is opening all of the way. Have someone slide the heat control from cold to hot and watch the cable slide the arm back and forth.
Might want to check your heater control valve too. That is the U shaped thing on the firewall above the motor. Make sure that it is opening all of the way. Have someone slide the heat control from cold to hot and watch the cable slide the arm back and forth.
- Thread starter
- #11
No worries about the FSM. What I can find on the entry all says the FSM isn't much help anyways. I already know how to pull the dash, so that's probably 70% of the battle (I hope).
Yeah, checking the heater control valve is smart.
I think my plan for this is gonna be-
1) Check the heater control valve
2) Flush the heater core (for fun)
3) Pull the heater core and install "new"
Check results at the end of each step, see what the results are. If nothing else, the flush might get me through the winter. I have to go back into the dash eventually anyways.
Yeah, checking the heater control valve is smart.
I think my plan for this is gonna be-
1) Check the heater control valve
2) Flush the heater core (for fun)
3) Pull the heater core and install "new"
Check results at the end of each step, see what the results are. If nothing else, the flush might get me through the winter. I have to go back into the dash eventually anyways.
That's the order I would do it.
The main issue with the heater core is that the vents in the valance (at the bottom of the windshield before your hood) allow debris of all kinds to get sucked down in to the core. There's no escaping it. No filter. A few have put "filters" in there but nothing drop in.
Post up how it goes. Good luck.
The main issue with the heater core is that the vents in the valance (at the bottom of the windshield before your hood) allow debris of all kinds to get sucked down in to the core. There's no escaping it. No filter. A few have put "filters" in there but nothing drop in.
Post up how it goes. Good luck.
I cut perforated stainless sheet to size and installed them under the valance to keep the debris out. I believe the perforations are about 1/8th". Keeps the twigs, leaves and other falling crap out of the vents. A clean look to boot.
- Thread starter
- #15
See, this stuff really makes me think my heater core is clogged up with gunk. Last fall (2015) I noticed a lot of junk falling into the vents from trees on my street. That fall I noticed a big decrease in heat, but not enough to worry about. This fall it probably got even more tree bits and leaves falling in there and now the heat has decreased even more.
If only I could clean out those vents without pulling the dash...
If only I could clean out those vents without pulling the dash...
My heat is barely warm, but my AC blows icicles. If the heatercore exterior were really clogged with detritus, wouldn't the AC have decreased flow as well?
- Thread starter
- #18
Here's another great heater problem thread. Sometime it's all about getting the search key phrases juuuust right.
FJ80 heater woes. Need help too.
FJ80 heater woes. Need help too.
- Thread starter
- #19
Also, does anyone know if the FJ62 heater core is compatible with the FJ80 heater core? It sounds like the 91-98 heater cores are all compatible. I'm wondering if it might be the same for the 62- I have a 62 I can get parts off of, so this could be pretty handy.