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Volvo 850 Heater Core Replacement Tutorial

Ready for a Heater Core Replacement Tutorial?

Tutorial: Replace the heater core on a 1993-2000 Volvo 850, S70, V70, C70 and XC70

Heater coreThis post should apply to all 850s and first generation 850, S70, V70, C70 and XC70 Volvos. I chose to go with showing how the heater coupling is replaced in addition to the heater core as when I attempted to replace JUST the heater core I had leaking in the cockpit. This may have been in part my badly rusted IRON heater pipes, which I replaced with the newer aluminium ones from V70/later 850. As the inner seal kit is not available the only choice is to replace the entire coupling.

taxidad :

“I fitted my new heater core today. When putting it back together I had trouble mating the coupling with the plate in the firewall with nothing behind the coupling to keep it in place. I also dented the fins on the core in one spot getting it back into it’s casing. I hope this doesn’t cause any problems. I notice in the pics above on the 850 you seemed to have plenty of room to undo those screws in the engine bay. I had a round disc shaped item in the way & wasn’t game to undo it. I managed but it took a while & a bit of skin off the knuckles lol. I got it all back together & started it up to check for leaks. First thing was – yes – I had warm air. Then, right at the point where the pipes enter the core – slow drip, even though I had cleaned up & put new O rings on the end. So I undid the casing, gently pulled the core down and pulled it sideways as best I could because it appeared to be leaking from the least accesible torx screw on the yoke that the pipes run through. I had unscrewed them before realising I didn’t need to. I tightened all the screws again & got it back together. Ran for 5 mins with no leaks. I turned off the engine & started to pack up. Just before I put the kick panel back on I had another quick look. It had dripped, oh (%$#&^%). I think it’s a VERY slow drip. It might even seal completely when everything is up to operating temp. I don’t have time to go in again for a few days, so I hope it’s slow enough not to cause concern. I drove the car about 5 K’s & can’t smell any coolant. I’ll be keeping a close eye on the water level until I can go in again…”


Volvo 850 Heater Core Replacement Tutorial

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I just replaced my heater core, it went super easy and quick (I had the old core out of the car in 12 minutes?!)

My only issue was having to tighten the coolant lines with a ratchet due to leakage. Then realized…what’s that little bag of O-rings on my seat? But in 5 minutes and another half gallon of coolant it is all set now.

This was super easy in my 2000 V70 XC. You don’t need to spend huge dollars at a dealer to fix this!

IPD has a great video on youtube on this, just search “V70 heater core”

kendash2000 says:

I am not a gear head, but I watched the tutorial (link below) and it took much less than an hour to complete. Use an OEM part, it is worth the couple extra dollars. What was most surprising was how well the panels went back together.

There are also questions, on the web for removing the coolant built up on the inside of the windshield. Exterior windshield washer fluid is the only thing that works. Soak a paper towel and wiped clean with dry towel, takes a couple times to get all residue.

Im having an issue getting the heater core from the black sleeve. I have a volvo v70 xc 2001. I have pulled both pins on the aluminum tubes, but there is a little black relay that is attached to my brake pedal that is preventing the heater from just being pulled straight out, I have the car inoperative at the moment till I can figure out how to remove the heater core, any advice would be greatly appreciated. Thank you

I have a 2000 volvo s70 non turbo.The heater core went bad and the pipes where rusty .got new pipes and heater core and also got a new connectors because when I was removing the old pipes I broke the connections at the firewall.I putting that new piece in but I dont know where way it installs (the piece that attaches to the firewall)It has a little straight place on the part I dont know if that goes up or down and that is where I am stuck…yes I am dumb

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