Hello all. My front heat has always been lacking especially compared to the rear heat. I have no known coolant leaks and have the front heater core flushed multiple times. I have a theory that there could be dirt in the housing. I’m basing this on the fact there was a lot dirt/debris/grime on my ac evaporator when i cleaned it out a couple of years ago. I have considered replacing the core but I was wondering if anyone has any ideas to clean the exterior/fins of the core without exposing it. I didn’t know if there is a type of fogging device or steamer or just anything else I could try before completely disassembling the dash. Any help or advice is always appreciated. Thanks
Front Heater Core-Exterior Cleaning
- Thread starter Nightbrew
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
RoaringFork
SILVER Star
In my opinion, if you’re gonna Go through pulling it out, just replace it.
I am in the same boat, my rear heat works great but my front sucks. I have tried everything short of replacing the heater core.
- Thread starter
- #4
If tear the dash out, there will be a replacement core near by. However I’m trying to avoid that altogether.
RoaringFork
SILVER Star
I hear ya... you said you’ve flushed it... did you use chemicals?? I’ve seen write ups ups of filling the core with CLR, and letting sit. Then flush it with water...
Have you checked or replaced the heater core diverter valve on the firewall and the heater core hoses?
One of my hoses at the diverter valve had a internal delamination from the fabric reinforcement in the hose. It had an internal bulge that was restricting flow.
I have also seen a piece of the barb portion of the diverter valve break off and get stuck in the valve butterfly and impede flow.
Both of these scenarios are basically like having the diverter valve partially closed.
I have also read in a thread that the steel tube that runs along the passenger side for the head from the front by the thermostat can corrode and restrict flow.
One of my hoses at the diverter valve had a internal delamination from the fabric reinforcement in the hose. It had an internal bulge that was restricting flow.
I have also seen a piece of the barb portion of the diverter valve break off and get stuck in the valve butterfly and impede flow.
Both of these scenarios are basically like having the diverter valve partially closed.
I have also read in a thread that the steel tube that runs along the passenger side for the head from the front by the thermostat can corrode and restrict flow.
- Thread starter
- #7
I have never actually done it myself. Had it done by my mechanic while in the shop for other work. He said they use some type of cleaner/chemical but I don’t recall what it was.
- Thread starter
- #8
By diverter valve do you mean the heater control valve? If so it was replaced about 2 years ago. Unless I’m missing something the valve should be working correctly as I am getting sufficient flow to operate the rear heat. Please correct if I am wrong. Thanks
RoaringFork
SILVER Star
You are correct... any flow impedance would affect both front and rear heaters.
RoaringFork
SILVER Star
If you trust that they did what they said then it’s probably time for a new one.
I’ve flushed my core, just water no chemicals. It’s tight working on the firewall(especially if it’s lifted) to isolate just front core. I could see how someone could get lazy and not be thorough.
In hind sight I wish I would have tried CLR, I got a small improvent, but my rear heater is till hotter...
Yes, diverter valve and Heater Control Valve are the same.
- Thread starter
- #12
I will do my own flushing/clr clean before tearing everything apart. I should also ask what are chances this theory of mine, that there could be dirt grime etc on the outside of core, being possible? Or would most of this debris collect in another location?
RoaringFork
SILVER Star
I don’t buy it... if it’s flowing hot coolant is gonna be hot! I’ll try and dig up the CLR flush thread...
RoaringFork
SILVER Star
Front heater core flushed with CLR now producing 135 degree vent heat.
It’s from @SUMMIT CRUISERS a trust worthy source IMO...
It’s from @SUMMIT CRUISERS a trust worthy source IMO...
- Thread starter
- #15
Thanks. I was just reading that
If you open up the dash to get to the evap/heater cores i think your going to shocked by the amount of crap that can be stuck to their cores.
I did one for a customer once, his wife said that every time she used the AC it always smelled like a wet dog. And yes he was a dog owner, when i opened up the evap core it had enough dog hair on it to cover a small dog.
In the case of your heater core, don't be shocked if you find it packed with leaves, pine needles, grass, dirt, and maybe even a mouse nest.
One last thing, the heater core for the pre 95 land Cruisers are now NLA from Toyota, so if you think you need one I'd buy it now, and the hard coolant tubes too. No telling how long the stock of 95 to 97 heater cores will last, before they too end up on the NLA list.
I did one for a customer once, his wife said that every time she used the AC it always smelled like a wet dog. And yes he was a dog owner, when i opened up the evap core it had enough dog hair on it to cover a small dog.
In the case of your heater core, don't be shocked if you find it packed with leaves, pine needles, grass, dirt, and maybe even a mouse nest.
One last thing, the heater core for the pre 95 land Cruisers are now NLA from Toyota, so if you think you need one I'd buy it now, and the hard coolant tubes too. No telling how long the stock of 95 to 97 heater cores will last, before they too end up on the NLA list.
- Thread starter
- #17
Good info. Mine is ‘96. Does anyone have part #’s for the tubes?
Are you sure? Mine had a November '95 production date making it a '96 and Dealership and Toyota on-line parts are showing this as NLA. Mine is leaking. Anyone that points me in the direction of a new one gets a case of PBR.
You'll have to forgive me, I'm over 60 so my memory isn't as good as it use to be so i may be mistaken. One person I'd contact if anybody may have what your looking for, would be Beno, he buys up lots of NOS Toyota parts before they become NLA for his shop.Are you sure? Mine had a November '95 production date making it a '96 and Dealership and Toyota on-line parts are showing this as NLA. Mine is leaking. Anyone that points me in the direction of a new one gets a case of PBR.
