Heater Core Flushing - OWNED!

[izzyandsue]

Now that cold temps are coming, I am reminded how puny the heat is on my truck. The rear seems pretty good, but front vents, suck-a-lo-fogus heat. So after reading and researching, looks like a proper heater core flush/clean is the thing to do (I have burped system already, little increase in temp).
The problem is , there is a lot of discussion about the flushing (and reverse) being a great solution, but no one shows how to do it or explains it to my 5th grade level intelligence.

Any one done that in an 80 and willing to share steps/photos? I am willing and able, just need to find some good intel on how. All I could find in the main forum was this pic showing 1-heater inlet and 2-heater outlet, connect hose to inlet for flush or outlet for reverse. My radiator is new, so don't think I need to mess with that as engine temp is good.

 

[lt1fire]

its pretty was to do. There should be some threads in the 80s section showing you how. I did it a few times increasing heat a little each time until I realized my blend doors weren't opening right. Once I fixed the doors my heat was great.

 

[izzyandsue]

Al, found lots of threads saying the same, its easy, etc. But nothing showing what to do. Thats my dilemma. I looked last winter too, not much. Then searched again today, found nothing new, so decided to see if anyone here had some detail info on how to do it.

 

[jamesurq]

Is there a blockage in the heater core?

IE: if you were to put your compressor on one end, is it free flowing out of the other end?

Pouring some 50/50 muraic acid / water into the core and letting it bubble up for a while could help eat away at the calcium deposits... assuming that's what's blocking it.

Be careful though - muraic is NASTY stuff.

PS Glad to see a question that I can answer has come up. Messed around with the heater core in my 70 Malibu back in the day...

 

[izzyandsue]

I don't know how to even get to it, so can't test. Which hose do I try to disconnect? Is the return correct on the photo above? Looking for someone who has done it and willing or has additional instructions. I hope it is blocked and thats the problem.

 

[jamesurq]

oh, I see. Sorry. I don't have a FSM but there should be one on here somewhere that you can reference.

 

[izzyandsue]

I got the FSM, read all there is there, but its not much.

 

[izzyandsue]

In ya face mama! I did it, I am not a total idiot (only partial idiot)! Here's what I did.

From Lowes got this morning

CLR 128 oz
10 ft of 5/8 ID Clear hose
6 ft automotive coolant hose (for the screw ups I knew would happen)
2 1/2" barbs coupling
1 brass hose connector to 5/8" barbed fitting ( most expensive item at $7)
1 hose connector with ball valve
1 gallon Toyota Rd coolant
3/4" hose band clamps
5 gallon Home Depot bucket
Shop vac connected to blow air
Clean funnel

Stole my wife's remaining distilled water . Don't tell her.

 

[izzyandsue]

The process.
Remove the hell spawned Toyota hose clamps for the U shaped hard pipe and the heater return rubber hose
Remove the u shaped piece and the rubber return
Cut clear hose in half, insert 1/2" barbed coupling on each one.

Insert barbed coupling on heater intake rubber little piece, secure with clamp

Connect the other 1/2" barbed fitting and clear hose to the outlet black hose from the heater

Connect the hose coupling with valve closed to the outlet side clear hose. This is for the first reverse flush.

Turn the hose on low at the home source, less than 1/2 turn, insert clear hose into bucket, slowly open valve, let water flow and coolant from heaters. Nasty crud.

I found that after flushing and filling up bucket, small valve turns on, off for a few seconds, then on again for a few seconds, repeat, removes more crap from system.

 

[izzyandsue]

After water flushes clear, turnoff hose valve and remove hose from barbed fitting. Connect fitting to shop vac and remove as much water from system as possible by blowing air into it.

Now use clean funnel connected to inlet side of heater clear hose and pour CLR slowly, until you see the greenish fluid coming out of other clear hose. Let it sit for 15 minutes.

Now reconnect the hose and slowly turn valve on, flush CLR out. You will fill two to three full buckets until clean. Cycle valve on and off as before.

I repeated the process twice. Then reversed the hoses to flush in the coolant flow direction, again pulsing the valve in the hose to clear any remaining crap.
Then use the shop vac again to push any remaining water out.
Finally use the funnel to pre-fill coolant into heaters
Reconnect everything and throw away the hellacious clamps.
Now with everything buttoned up, turn motor on and burp system, let the sucker run for a while to ensure thermostat opens. I ran the motor 20 mins in the driveway.

 

[izzyandsue]

And the money shot. It used to peak at 97F on Low blower setting, now sitting in driveway I got 150F on High fan! Suck it Frosty!!!

The bad news, while burping the system, I realize there is a lot of dirt in radiator, will need to drain and clean the whole thang. How do I do that?

 

[izzyandsue]

Back flush in action, exciting!

 

[fourtrax]

well done!!

 

[lumbee1]

Awesome write up! I've got to flush my entire system sometime soon. Previous owner or previous previous owner filled the truck with green. I want to clean the system and fill with Toyota red. HAMOM?

 

[izzyandsue]

I am game. No idea how to do the flush, and instructions I found are vague at best (drain and refill, but drain and refill what?). Looking for videos when I get a chance. Seems like the Gunk Super Strength is the best out there.

 

[JohnVee]

Awesome write up! I've got to flush my entire system sometime soon. Previous owner or previous previous owner filled the truck with green. I want to clean the system and fill with Toyota red. HAMOM?

I think that even Beno has said not to bother going back to red if green has been used.


...via IH8MUD app

 

[izzyandsue]

Found a good flushing video, turn the close caption on (CC) and pause it at 1:23. Got to love the auto CC function of YouTube.

 

[lumbee1]

I think that even Beno has said not to bother going back to red if green has been used.


...via IH8MUD app

Thanks for that JV.

 

[NCFJ]

Just don't mix the two, completely flush the system before switching either way.

 

[izzyandsue]