Poor heat on outside air/Good heat recirc mode

[5rebel9]

Yes I'm back. Been a crazy 2 months of 2022 due to a family medical crisis and multiple sub 0*F temps.

 

I look to the long  term members here for their experiences with getting heat in the extreme cold. I know the heater core on our '11 model needs replacing, but have found that even the drivers side is getting cold when using the outside air source(defrost or otherwise). Tried using recirc mode without the A/C and got really decent heat back on the drivers side with some heat on the pass. side. These conditions are from minimum driving times of 20 minutes or longer, and NOT from short or city driving speed "hops".

 I'm wondering if the outside air INTAKE may be a bit too large, allowing too much outside air in thus overpowering what the heater core can produce?

[tsteves5]

You made me curious, so I ran some tests.

 

I replaced the heater core on my 2011 about 10 months ago.

 

It's 12 degrees F outside, my coolant temp is 195.

With my IR thermometer, I'm seeing about 157 on the driver's side using outside air.

Switched to recirc (non-AC) mode, waited about 10 minutes and I'm seeing about 168 on the same vent.

 

So in my case, the heater core seems mostly capable of keeping up with the colder outside air.

[5rebel9]

Yes, I forgot to say that coolant temp is running at about 195(up to 204) also I know better to NOT gripe while coolant temp is still low.. I know I have the "traditional" clogged core for right side heat, maybe if I could ever get that "roundtoit" time and change the core that thing would be much improved. But we've had to drive it in temps reading as low as -15f and it's been downright COLD in the car, even up to 20 minutes of 55mph driving time. Windshield does "defrost still, but if placing a hand near those vents it is COLD. Non A/C recirc mode brings back good interior heat(dash/dash/floor}.

Any setting that automatically uses outside air draw is COLD.

 

Medical crisis is my 87yr. old Dad suffered a major stroke and then heart attack on 1/2/22 and is currently paralized on left side. Been with him 6 days a week during the days. His mind is as sharp as ever, but can't convince him that he can't try and do things as normal. Puts a strain on all the family, as he's "fallen" 3 times trying to get out of bed or wheelchair by himself. .

[tsteves5]

2 hours ago, 5rebel9 said:

Yes, I forgot to say that coolant temp is running at about 195(up to 204) also I know better to NOT gripe while coolant temp is still low.. I know I have the "traditional" clogged core for right side heat, maybe if I could ever get that "roundtoit" time and change the core that thing would be much improved. But we've had to drive it in temps reading as low as -15f and it's been downright COLD in the car, even up to 20 minutes of 55mph driving time. Windshield does "defrost still, but if placing a hand near those vents it is COLD. Non A/C recirc mode brings back good interior heat(dash/dash/floor}.

Any setting that automatically uses outside air draw is COLD.

 

Medical crisis is my 87yr. old Dad suffered a major stroke and then heart attack on 1/2/22 and is currently paralized on left side. Been with him 6 days a week during the days. His mind is as sharp as ever, but can't convince him that he can't try and do things as normal. Puts a strain on all the family, as he's "fallen" 3 times trying to get out of bed or wheelchair by himself. .

 

Sorry for your troubles.

[5rebel9]

After finally finding my thread here on the forum .....

 while my friend is "mending" from hip surgery I had TIME to really talk with him about this situation. YES I've checked that the pass. side blend door actuator is working AND moving the white arm that actuator hook up to. BUT he says that now I need to remove the actuator AND arm to check that the pins and groove on the HVAC box side are actually there and were aligned into the groove of the white "arm" on that side ot HEAVEN FORBID that either is broken. Says he has spare "arms for my taking, but both of us are now concerned that the posts that ride in  the inboard side groove may be broken. 

     Going to have to finangle the "11 Journey away from my son for a fair amount of time to get into the job and check this out  ... BRFORE I finally go for the heater core replacement I had been preparing to do!   

[5rebel9]

Fimally got the car for TWO DAYS! The pass side blend door and linkages are OK, it is DEFINITELY the HEATER CORE. Going to do my best to replace it tomorrow (Saturday).

[2late4u]

might want to replace your thermostat as well since you will have to bleed the system anyways really easy on the 3.6 around $20-25 for the part, had to do mine earlier this yr as well,, i am sure your aware of the youtube shortcut on replacing the heater core,, good luck and take care

[5rebel9]

T-stat is one year old and temps there are fine. But  with 217+k miles, I'm not about to try removing the dash to do the job. YES I'm going to cut the tubes and hose connect the new one in.

 Just relieved to know for certain now that it is the core, as some other forums have talked about broken blend doors that HAVE TO pull the dash to remove/repair the HVAC box. 

[5rebel9]

As in the last words of Jesus when he died on the cross  ...  IT IS FINISHED !

 

Better partr of 5 hours with my lack of contortionist body and taking my time to not risk breaking anything. Found a few tricks NOT discussed on you tubes, and DEFINITELY different than  the '08 -'10 models. But got the job done and MAYBE when time permits I'll write up the couple trcks I used doing the job. Right now, I'm WORN OUT and ready to CRASH!

OH, BTW I also got roped into topping up the R-134a (1 1/4 lb cans) to get his A/C cooling again that he just told me of last night!

[2late4u]

from the angle of the part and the seat might have paid to remove the drivers seat just for the sake of making it easier to access the heater core

LOL a few months ago i replaced the cabin air filter on my grandsons 2018 altima and  well that will be the last time i will do it, they couldn't have have put it in the worst place and angle as well, i hurt for days after doing it took me over an half hr to get it in there right

Edited August 27, 2022 by 2late4u

[John/Horace]

Was airbag bracket in dash bent out of the way to remove coil.?

Instead of using pieces of heater hose to splice in new coil, was loosening crimp connections and redoing a decent option ; or did it appear too risky for leaks. 
I’m not looking forward to this repair, might do another dump and fill of the glycol to help avoid jell forming in heater core.

This is similar to the problems Dexcool use to create in GM products.

 

[5rebel9]

3 minutes ago, John/Horace said:

Was airbag bracket in dash bent out of the way to remove coil.?

Instead of using pieces of heater hose to splice in new coil, was loosening crimp connections and redoing a decent option ; or did it appear too risky for leaks. 
I’m not looking forward to this repair, might do another dump and fill of the glycol to help avoid jell forming in heater core.

This is similar to the problems Dexcool use to create in GM products.

 

First trick is when taking out the "to floor" duct ... It's a 2 piece duct thet "pops" apart. The section next to the "stinking bracket" will give easy acees to remove the part that latches to the HVAC box.

Next trick I did was to slice the bracket you describe with an air powered small cut off tool , just to the short sides of that bracket. then bet the lower carea of the bracket inward with vice grips so when bending back towards the steering shaft, they didn't bind. Once sliced like that the bracket will bend quite easily with pliers. I also bent the mount tab at the bottom easily with pliers to gain the last 1/2 " needed to slide out the core. All straightens back nicely for reassembly.

I initially opened the crimps and popped the tubes(lower one first) with an empty 2lb coffee can placed below to let the core drain into. NARY a drop fell onto the floor, but I did have an old bath towel there also(just in case) I did NOT drain the coolant down before starting the job!

   The replacement core had much stouter aluminum metal for the cores tube crimp area, so I decided to cut the tubes and use 5/8" heater hose. Yes it's a tight fit to slide, but CARPENTERS TRICK of a light smear of "DAWN" dish soap helped greatly in getting things positioned for good "fit" 

  Watch out  for the size type screw clamps being used. I used "heavy duty" 5/8" clamps, and had to grind out some plastic of the floor duct (has a seies of "nubs) for vibration controlwhere it sits against the tubes and HVAC BOX  to get the duct back in and fit flush for the phillips screw to go back in. This took me the most time as it was multiple trial cuts to get right. That cut off tool made things pretty quick, but didn't want to go too far to fast and ruin the duct.

 

 NOT that I WANT to do more of these jobs, but I'd say that the next time would be a lot quicker, now that I've done this one!

And I had just happened to be asked by my friend on Friday of HOW I went about trying to FLUSH the core last fall(which helped some but not enough) with CLR. I Think he's got a possible poor heat job coming in and actually wants me to do it for him. I'm supposed to call him Monday and tell him what I thought about the replacement job(and how I did it).

 

 I HOPE THIS HELPS YOU AND OTHERS THAT MAY WANT TO TRY THIS JOB.

 

 

 

[John/Horace]

Thanks for the follow up. One last thing, what brand of core did you use,  just curious. Thickness of piping might indicate overall quality of coil. 

Still running the pink or are you back to old school green long life glycol. 

[5rebel9]

4 hours ago, John/Horace said:

Thanks for the follow up. One last thing, what brand of core did you use,  just curious. Thickness of piping might indicate overall quality of coil. 

Still running the pink or are you back to old school green long life glycol. 

I've been using Peak Blue Mountain Long life for all vehicles since we got the journey and don't see a problem with it.  Remember it had almost 180k Miles on it when we got it and coolant was DEFINITLY not the "pink" color type.

 The core came from rockauto, and I believe the mfg. was SPECTRE. IF the metal thicknes was the same as the plugged up one, I would have tried just crimping the old tubes to the new core. I gave ONE TRY at an easy to get to crimp of the new core, and it bent my screwdriver shank without moving the crimp away. SO CUT THE TUBES and used hose.

 

And NO I did NOT cut the core open to see the insides, The old core is now at my friends place and he says HE will cut it open and look at it when he has some spare time.

Edited August 29, 2022 by 5rebel9

[5rebel9]

Well my son has driven the '11 DJ for 3 days now and reports that the A/C is working FINE now, and the heat is much better than before as he needed to clear windshield fog last evening due to the humidity and nearly 1" of rain we got yesterday. Says pass side was a little slower to clear than drivers side, but a LOT better than before changing the heater core. OF COURSE the "acid test" will be when we get actual COLD temps to see just what we gained with the "job"!

NO LEAKS, DRIPS or ERRORS !     

Edited August 31, 2022 by 5rebel9

[John/Horace]

I think you will be good with the new core now. Was on a Jeep forum and I came across this info about coolant changes from orange HOAT to green glycol.

Previous owner of your truck not switching properly may have created your gel/sludge problem. I think staying with orange and doing dump and fill and maybe chemical flush if high milage, might help avoid heater core issues. 
 

 

– For HOAT (orange) coolant engines, NEVER JUST CONVERT TO GLYCOL. This will completely Sluj(R) the system and kill it. Multiple Mopar 04856977AC flushes, run on water for a while, then another flush.
– For HOAT coolant engines, you absolutely must not mix or change without aggressive chemical flushing. That includes mixing with any other OAT or glycol.
– For HOAT coolant engines, Mopar HOAT or Zerex G-05 

 

 

 

 

 

 

Edited September 1, 2022 by John/Horace

[5rebel9]

I agree rith what you posted John/Horace, Buying something from out of the area USED with no history is always a gamble. BUT this overall body confition of this DJ was well worth it, I spent the better part of my life as an auto tech so not afraid to get "into" vehicles for repairs. When a person is jumping into a FIRST TIME of a certain repair, a good tech/DIY person will amass as much info about the job BEFORE "digging in".That is what I had done thru all this SAGA while TRYING to have weather and scheduling coincide to be able to "GIT ER DONE".  I had pretty much concluded from date of purchase that it needed a heater core, but also had possible control issues in my mind due to info searching and lack of "play time" with the car.      

[5rebel9]

Well, we went down to 30*f and goodly frost last night/EARLY morning. Son reports excellent windshield defrost and HEAT in the car within 2 minutes of startup and traveling "down the road".

Greatly relieved for this after replacing the heater core in the 2011 with 220K miles ! 

 

Wife's 2014 defrosted very well and great heat right off also! With the 70k mile motor it got and fresh coolant and T-stat, both cars should be good for a couple years now!

[jkeaton]

14 hours ago, Christysycle said:

No kidding, good pics

Im just not sure I would wanna hook knife a perfectly good chute and rely on the reserve to deploy . . . I wonder if he had a spare reserve?

 

Are you in the wrong forum?? Who are you talking to??? lol