Heater Not Functioning - Need Coolant Flush?

4

4runner001

New member
Now that it's finally getting cold here in Texas, I found that my heater does not function well. After about 15 minutes of driving, it will finally blow warm air. But still not as hot as it should be. A/C blows cold.

I've attached a picture of my radiator which contains some deposits near the top.

Would a complete flush of the coolant and replacement with Toyota OEM coolant help? Maybe there is something else I should check?

Thanks!

84b51e0a4f39eb0a49b3db64286dbf19.jpg
 
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I am no expert but your coolant system has seen better days. I would think you have some flow issues in your heating components for sure. A cleaning and flush for sure.....I would even let it sit and soak for a while and maybe more than one time.
 
Here is how to fix it:

1) drain and flush you coolant.

2) Purchase and install a new radiator if it is the original.

3) Disconnect the inlet and outlet hoses going into the heater core. These are the two thin black tubes going into and out of the firewall (let me know if you need pictures).

4) Using a funnel, fill up the inlet tube with CLR (calcium, lime, rust remover) until it starts to flow out the outlet tube. Plug, elevate, or pinch off the outlet tube so the CLR will stay in there.

5) Let the CLR soak for 15 minutes.

6) Using compressed air, carefully blow air into the inlet tube. Tons of crap will fly out of the outlet side, so have a rag ready to catch it. This will be extremely messy.

7) Repeat one more time if necessary.

8) Drain and flush coolant system WITH BOTH HEATERS ON FULL HOT.

9) Enjoy perfect heat.
 
It's time to get on your knees and pray to God it's not your heater core or that if it is the heater core, [MENTION=117677]A-dog[/MENTION]'s steps resolve it.

Even if you don't believe in God, this is the time to my son, this is the time.

BTW, your coolant looks like Tomato soup you can order from Panera.
 
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I was told...To flush you heater core. You need to put some water and blow it back and forth to loosen up any build up. Then blow it all out. Blowing it isn't going to loosen anything up. This blowing back and forth is.
 
amalik said:
It's time to get on your knees and pray to God it's not your heater core or that if it is the heater core, [MENTION=117677]A-dog[/MENTION]'s steps resolve it.

Even if you don't believe in God, this is the time to my son, this is the time.

BTW, your coolant looks like Tomato soup you can order from Panera.
Click to expand...

Lol yup. Or your whole DASH is coming out bud.
 
You may have bigger issues based on the color of that plastic tank, I'd replace that & thermo/gasket first....
 
^^^^ This...the thermostat will likely fix your heat issue and the new radiator to avoid the pink milkshake.

Buckaroo
 
4runner001 said:
Now that it's finally getting cold here in Texas
Click to expand...

lol. That's cute.

And yeah, I concur with the others. Time for a coolant system overhaul.

Sounds like your heater core is potentially clogged, hopefully [MENTION=117677]A-dog[/MENTION] 's steps will do the trick.

I'll be praying with you and [MENTION=99383]amalik[/MENTION]. lol.
 
looks like that radiator I had back in the old days early 80's.

I HAVE OLD HIGH MILE VEHICLES.. I do all this type repair work. the coolant systems require distilled water and the proper antifreeze of at least 50%. using other water will cause all that crap to grow and plug up your coolant system.

I have a 1996 that I just did the coolant servicing. 3.5years was the last servicing . the pressure tank had no crap in it at all. reason is no dirty water used only distilled. I also use 65% antifreeze because of the additives that prevent corrosion.

many in the warmer regions do not use the proper amount of antifreeze and also use bad water sure you may not require that heater to work 100% like up where I live but when summer heat arrives that engine will get cooked.

I would do a complete block drain , remove T stat. flush the heater core, run with distilled water and some cleaner product for a few miles then drain it all out flush it then if clean use the proper coolant and distilled water.

put T stat back in if its cleaned

I would also use only the same product in this do not mix different coolants ..
 
If I were you, I'd replace the radiator first. Then before refilling, I would flush out the heater core using the CLR method described above. Do not apply to much pressure to the heater core because it can rupture, you would be screwed.

Once that was flushed out good, I would then refill the system with distilled water and a coolant flush product (follow directions on the product). Once that was all done, I would drain again and fill back up with Toyota coolant.

Your entire system will be flushed and clean. Your heat should work wonderful again.

Good luck
 
Here is my input:

Disconnect the rubber hoses attached to the heater core from the other ends (not right on the heater core): Reason: If you bend one of those soft Aluminum tube, that is it. You are removing the entire dash to get it fixed. So remove the other ends of the rubber hoses.

Attach a connector and run two rubber hoses each about 3 feet long.

Use your garden hose (WITH LOW PRESSURE), apply it to one hose and let the dirt to come out from the other hose. Repeat this with switching the two hoses until you get clear water. Finally pour some distilled water into the heater core through one of the attached hose and call it done. IF water is RUNNING THROUGH the heater core, call your self lucky! and take day off!

Remove there thermostat housing and thermostat

Block the two open ends of the heater core line on the engine end.

Use the same garden hose and run water (again low pressure) from the top of the engine (coolant outlet) and let it come out from the bottom. Do this for good few minutes.
Final run 1-2 gallons of distilled water to flush out city water in the engine core

Get a new DENSO radiator and OEM hoses (about $17 a piece). Attach it and connect all removed rubber hoses and thermostat and fill the radiator with proper coolant. Toyota OEM red coolant is the best $ 25 a gallon and you will need two.

Fill the radiator with 50:50 mixture of coolant and distilled water.
 
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Wow! So much good knowledge on this forum! Thank you!

I bought the vehicle this summer and it currently has 177,000 miles. It had one owner but not sure of it's maintenance record. Really appreciate the detailed instructions and advice that all of you have provided.

I'm hoping I don't have to start taking the dash apart, but let's see.
 
One of top five things to do before buying a used car or truck is to look under the radiator cap. Always.

+1 on always using distilled water. Somehow owners forget that automobiles rely on the properties of chemistry and physics to work correctly.
 
Thermostat

Agreed with all of the above regarding new radiator, coolant system flush, heater core flush, etc. It will save you major headaches down the road.

But: Where is your temp gauge after the engine has been running for awhile? A stuck open thermostat will result in no heat, because the engine never comes up to operating temp.
 
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