Heater Core Replacement

[bhicks]

Went and looked at a used 95 FJ80 today. It was super clean in and out, 145k, and lockers. Exactly what I have been looking for. HIs asking price was right under my budget so I was happy. There was one issue that I notiiced. The entire heating system had been bypassed. The current owner said it was like that when he bought it 8 years ago. Since were in Socal it didn't bother him, but I'm at close to 7000 ft elevation and get a LOT of snow so it bothers me. It has the rear heat as well but neither the front or rear are functional. The seller told me that the guy he bought it from said it had a bad heater core. Now to the question. How complicated is it to replace the heater core? I held off on buying it today and told him I would look into the cost of the repari and he could get it smogged then we can meet back up tomorrow to come up with a price on his 80. On my WJ it is a nightmare. The entire dash had to come out. I REALLY hope I don't have to do that again.

 

[bhicks]

Fraaaakk!!!! I had to go back 6 years on this forum to find a write up. Not good news. Looks like I have to remove the entire dash and some. What a HUGE PITA!! I will be calling my mechanic in the morning and getting a quote from him. I will also send him the link below so he knows exactly what he will be doing and can give me an accurate quote. I will take his quote and the printed out write up with me and tell the buyer he needs to remove that cost from his asking price and we have deal. Hopefully that will work. Here's the link.

https://forum.ih8mud.com/80-series-tech/222486-94-heater-core-r-r-done.html

 

[Sc0-]

Yep, the heater core on mine is currently leaking on the passenger side floormat and have been digging up those old threads as well for the procedure...


One of the the threads mentioned soldering the drivers side tube to the heater core instead of relying on an O-ring seal and 1-less place for leaks...

 

[landtoy80]

I did a heater core on my 87 Supra and its was a major job. I ended up with many extra bolts and screws. If you dare to try it, mark where the bolts and screws came from. Be ready for lots of work...

 

[GrawDaddy]

Hi Guys,

My '93 is starting to blow that sweet coolant smell through the vents when it warms up. I think it is a heater core. Are there any other things I can check before taking on this project?

 

[landtoy80]

Look under hood at heater valve. I had a leak there and could smell coolant as it next to the fresh air intake.

If its not leaking but you may want to try GM Cooling System Tabs also sold by AC/Delco. I used them in other other vehicles with no issue. I am not sure if I tried them in the 80 or if it was in the 60 or 62???. I have not read where THESE have cause issues with cooling system but have not read about them in several years.

 

[Phildoh]

Look under hood at heater valve. I had a leak there and could smell coolant as it next to the fresh air intake.

If its not leaking but you may want to try GM Cooling System Tabs also sold by AC/Delco. I used them in other other vehicles with no issue. I am not sure if I tried them in the 80 or if it was in the 60 or 62???. I have not read where THESE have cause issues with cooling system but have not read about them in several years.

I've used them before, work great! Never used them in an 80 though!

 

[Hornd]

If I was going that far, I would change the expansion valve and clean the Evap core while it was apart.
The Denso Expansion Valve from Rock is cheap and it is 21 yrs old. I did the Evap core in one night and it sits just to the RH of the Heater Core.

 

[BlueCruiser84]

I did the heater core. It sucked. There is a thread somewhere. It's not hard, but it does take a while and there is lots of stuff to keep straight. EVERYTHING comes out of the front except the wiring harness.

 

[series10055155]

I just had an extreamly wet driver floor mat. My uncle who fixes my truck believed it was my heater core.

My driver side May was wet from underneath the mat as apposed to from the top of it.

It was about a gallon or 2 of water sitting in my frame from a bad sun roof drain.

Check this first.