Poor output from heater/defrost vents

[xirdneh]

[/quote]

(old heater core with end caps de-soldered and removed)
i tried soaking one end of the heater core in some diet coke for about two hours
when i rinsed it off the slot ends were cleared
i will try the other end tonight

[/quote]


i soaked the other end all night and rinsed off but did not get as good of results as the first time.

[Petros]

did you use fresh Coke? Or does that mean it would work best to soak in vinegar first for a few hours, and then give it several hours in coke? Than rinse it out.

What next, chips and dip to go with it?

I will have to do this to mine, since I only get med warm air from my heater, and it is not pleasant in really cold weather.

[ARCHINSTL]

OK -
Now here is a thought - NOTE that I am NOT trying to be facetious about the Coke thing...
Would this seem valid: Remove the heater hoses, as in flushing them using the method Petros suggested - EXCEPT - filling the core with Coke through the hoses and letting it sit overnight - and then flushing with water through the hoses?
Again - I am not being facetious - the idea of Coke is more appealing than a harsh cleaner.

I confess, I feel like this post is like writing to the old "Ask Heloise" columns that used to run in papers. Heloise's answer to everything was "vinegar."
Tom M.

[xirdneh]

OK -
Now here is a thought - NOTE that I am NOT trying to be facetious about the Coke thing...
Would this seem valid: Remove the heater hoses, as in flushing them using the method Petros suggested - EXCEPT - filling the core with Coke through the hoses and letting it sit overnight - and then flushing with water through the hoses?
Again - I am not being facetious - the idea of Coke is more appealing than a harsh cleaner.

I confess, I feel like this post is like writing to the old "Ask Heloise" column here. Heloise's answer to everything was "vinegar."
Tom M.

i guess i should give some history on this
my wifes heater core failed
after replacing it i decided to take the old core apart to see what it looked like on the inside
the slots on both ends had white deposits that were hard and the slots were partially clogged with who knows what
i remembered reading in this site something about using vinegar to clean a core
so as an experiment i soaked one end in about 1/4 inch of vinegar
it did not seem to do anything
but a week or so later when someone asked me to try coke i dug out the core and noticed the end that was dipped in vinegar had deposits that had softened
anyways i dipped the end in coke for a few hours and it had cleared quite a bit of the blockage
lastly i tried dipping the other end in coke only with no good results

i cannot make any big claims here
since it was a half-assed experiment
i would like to try it again under more controlled circumstances but need an old core to sacrifice

[Snax]

So my question is: How hard is it to replace the core?

Mine is acting like it's 100% plugged now, so I have doubts about flushing being very effective.

Edit: Nevermind. All is answered here: https://tercel4wd.com/forums/viewtopic.php?f=4&t=4136

[ARCHINSTL]

I can't resist....
........................Vinegar with a Coke chaser......?

But seriously - this would seem that it would work better than Coke alone, based on xirdneh's experience.
Tom M.

[takza]

I'd reverse flush it with a hose first...and also use a length of heater hose to bypass the heater valve. I'd be real hesitant to tackle it in winter.

[ARCHINSTL]

I'd be real hesitant to tackle it in winter.

My thoughts exactly - especially with no garage.
Some heat trumps no heat,
Ahhh, the prudence of age...
I did the Weber this Fall instead of the heater.
Tom M.

[xirdneh]

I stuck a thermometer in the vent located above the heat controls and registered 155 degrees as highest temp . My friend did his tercel and got 90 degrees.
Both had system set at "Recirc" and the outside temp was around 50 degrees.
I asked my friend to try the coke/vinegar thing before replaceing the core. he said he would but it may be a while.

When i replaced the core in my wifes car I removed the front seats and removed all of the plastic under the full width of the dash. Pulled the radio and glove box ,blower assy and all of the plastic vents I could get out easily.
Then the metal brackets on each side of the radio/heater control console (removing these makes all the difference). This allowed me to push the heater controls and cables over towards the steering column (after disconnecting the cables at the "far end" attachent points). The center vent just above the heater controls was kind of hard to get out (one screw at top center). There was plenty of room now to pull the heater assy.

[Highlander]

Very interesting, I had my doubts about the Coke trick, but now I'm anxious to try it. I agree with Tom, that soaking the core in-situ would do the same as removing and soaking, as long as you take the valve out of the circuit and flush the core well afterwards. Do remember that Coke contains Phosphoric acid- the same thing that is in cleansers like CLR and the like, only in a much more dilute form, so it's not exactly not a harsh cleaner, it's just more dilute, so don't leave it in there for a long time- it probably will eat through given enough time.

[Neu]

why not just use some CLR or any type of calcium/lime/rust remover? Soak the heater core in it for a day, then remove it.

Or would that damage the heater core?

[Petros]

I once used a similar bathroom cleaner called "Limaway", the description sounded like it would be perfect for clearing away scale from a heater core. though it was not sold for automotive use. They make several types, the one I used was for coffee pots. I put it in the heater core and let is soak, but it was difficult to tell if it made any difference. A little worried it might be caustic I may have flushed it out too soon.

[Neu]

Yeh the thing i'd be worried about would be how weak that metal is. The heater core metal pretty much sucks, so a lot of different acids could probably destroy it.

I would think CLR would be fine though, since it's made to eat away at rust and lime/calcium buildups without harming the metal.

[Snax]

Well I am now convinced that a simple reverse water flush is probably the best first effort. I did this to mine on Sunday and have gone from zero heat to use-able heat within 2 minutes of starting it up. On a 50 degree, the one mile drive around my block was enough to force me into a sweat from the blower temperature.

Flush it. It's easy. It works!

[ARCHINSTL]

So, Snax...
Did you just unhook the heater inlet hose at the firewall valve, direct it into a bucket via a longer, attached, hose - and then attach a garden hose/nozzle to the heater outlet hose end (where it joins the pipe to the water pump). And then blast with mains' pressure - or a gentle flow?
How long did you let it blast/flow?
Nervous Nelly here...
Tom M.