Hi everyone,

I just replaced the heater core in my 95 850. It's a non-turbo 5 speed manual with 200k miles. Since we had the car (about a year) puffs of smoke/vapor would come out of the vents every so often. So I figured it was time to replace the heater core. I bought this heater core from fcp euro:

Volvo Heater Core (850 C70 S70 V70) FCP 9144221A | FCPEuro.com

After replacing the o-rings, the heater core, and the coupling, I started up the car and there was smoke and a burning smell all in the car. I've read online and people said it was from the foam and/or the coating on the heater core (why would an aluminum heat exchanger have a rust inhibitor coating?).

I just replaced it yesterday and did maybe 5 miles on it. Should I remove all the foam? Or will the smell go away? It's bad. I can't stop coughing and it makes my eyes water. So I'd like to fix the situation before it's too late. Any ideas/ anecdotes/ experience would be greatly appreciated.

Thanks

 

What kind of burning smell is it? If you think it will help, run the car full heat with the windows down for 10 minutes or so to see if it stops and goes away.

 

After I replaced my heater core, the heated air had the smell of aluminum, which I prefer to the smell of coolant steam.
Before I put it in, I rinsed out the core, running a bit of soap and tap water through it, and I also flushed water through the coils, blowing out any excess water. I also washed out the plastic housing which had quite a bit of crud from the old weatherstripping and other dirt.

 

Sorry I left out the most important details.

As for the foam, I put the foam on the same places that had foam on the previous heater core. It is touching the metal fins, but there was foam on the fins on the stock one.

The smell is like a metallic/ chemical smell. It is not coolant (I know that smell from the old leaky heater core).

When we took the car out last night, I gave it an Italian tune up for about 5 miles or so (probably 15-25 minutes) hoping the high heat would burn off the smell.

Today I wanted to check if it would get better and drove another 3 miles. And even before the coolant was up to temp, the smell was back.

The smell is worst when the heat is on and the fan is blowing on your face. Whatever it is, it is not good. My lungs are burning and I can't stop coughing and my girlfriend and best friend were suffering the same symptoms. This is my girlfriend's car and she has a long commute, so I don't want to put her in any danger (ie: passing out at high speeds, etc.) and I'm willing to spend the money on another heater core (oem even), I just want to make sure whatever I do will fix the smell or find out if it'll go away on its own.

Now I'm debating whether or not I should turn the heat on high since there is no valve controlling the coolant and hot coolant is always flowing through the heater core. Also, the fan may cool the heater core fins a bit and prevent the smell from burning off. So I can't even decide on the best method of trying to get rid of the smell.

Thanks again for your help.

 

Did it go away?

 

You can crank the temp **** to full heat and the fan to 1.

 

Maybe your new core is leaking? Appears you didn't get the OEM one.

 

I replaced mine about a month ago, I'm getting a smell also, pretty faint, I figured it was just "new part smell" I figure eventually it will go away. Sounds like you might have to go back in. Kinda sucks but you cant drive it if you're tossing your cookies...

 

I know I didn't get the OEM one. It's not leaking. I left the panel off just for that reason and the smell is distinctly not coolant.

 

Some long time posters here have had problems with non-OEM heater cores bursting within a year or so of installation.

I replaced mine w/OEM part about 3 yrs ago; never had an issue like yours; here's what i'd recommend:
1993-1997 Volvo 850 Heater Core

Note: OEM is about 2x the price of your aftermkt part.

 

Just an update everyone. We tried to wait it out. But it was getting to the point where our lungs hurt after a 30 minute drive (seriously). So I said screw that noise, ordered an oem heater core and replaced it, in a tick under 30 minutes.

Now everything is gravy. So a few hours later I got curious and started digging around to see what could've possibly caused that terrible smell. The aftermarket core was fine. The cheap foam included with the aftermarket core was the suspect. I put a lighter to it for a second and the smell was EXACTLY the same. So roughly a buck and some change of heat resistant foam would've fixed that right up. Good thing I spent about 100 times that. So if anyone has the same problem or if your heater core blows up. Buy oem or don't use the foam if you purchase an aftermarket core.

 

I recently read where someone said that some of these cores need to be washed real good before they are installed. To remove some kind of coating off them. You may want to post that one for sale in the classified section. Get a few dollars back.

 

Tried that. No dice. If someone wants it, I'll give it to them for the cost of shipping. Something was just plain wrong with it.

 

Replace my 98 V70 T5 heater core with FCP Groten heater core. Soaked the thing in "Dawn" dish washing detergent and then completely rinsed before installing. Let the thing dry and then installed the foam sealing tape.

The thing reaked like hot cardboard. I googled it and ended up here (among other places) and learned about the foam tape thing.

Finally got around to getting really annoyed with the smell and tore the new core out the other day It took about 10 minutes to get it out. I a used heavy duty "contractor" trash bag tucked UNDER the heater core and extending and covering the drivers side and tucked "up" on the driver side so all of the coolant would gush toward the drivers side. I started the car and put the heat on FULL COLD, then turned the car off. Removed core. This time there was ALOT less coolant than the first time I removed the thing.

Spent a LONG time REMOVING the foam tape and then sprayed the core all over with super "Orange" degreaser (Wal Mart), hosed it off, soaked it again with Orange stuff, hosed it off, THEN (just for good measure) soaked it for hours in a bucked full of HOT water and powdered laundry detergent. This loosened up the adhesive from the foam and and got it ALL off. After soaking in the laundry detergent all of the aluminum is now "discolored"... Looked this up - decided not to worry about it.

Stuck the thing BACK in (without ANY foam sealing tape) and hoped for the best. No leaks and NO SMELL AT ALL!!!!!

I'm not sure if it was the foam sealing tape or crap on the aluminum fins, etc. I'm assuming it was probably the foam.

The heat seams "hot enough". It was 12F out this morning and the car warmed up adequately. I am thinking that it was HOTTER and warmed up FASTER with the foam tape in there - unheated air leaking around the edges, etc - oh well.

Now I'm worried about the stoopid thing blowing up and spraying coolant all over the place, but for now at least I'm back in business.

Moral of the story...? Would it have been better to spend the extra $65 (the FCP core cost $65 and a Behr was around $130) or not? I have no idea. Do the Behrs have to be cleaned? Is the foam tape and adhesicve on the Behr's not appropriate for 200 degrees?

Anyone know? I suppose, depending on how much of a pain the defrost is this winter (live in IA), I may try to rig something to seal the the thing that won't melt/smell, or maybe just spring for a new "quality" core in the spring (or at least by next winter).

On my car when heat temp set to full OFF, NO coolant flows to the core at ALL (as far as I can tell).

Anyway, after all of this, I am still a bit "miffed" and would rather have not had to deal with the smell and having to do the job twice, although, as I said, doing it the second time only took about 10-15 to get out and less than that to put back in.

Thanks to all who post here - this is an invaluable resource.

 

Thanks for the info. Not sure if the foam or some core coating causes the core odor.

Besides that, I'm pretty sure that the temp selector has nothing to do with the amount of coolant that flows through the system. The temp selector(s) control the air door mixture which allows more air flow over the core. Older Volvo's had a heater control valve that blocked coolant flow, not these newer ('93+) cars.

 

I own a 1995 Volvo 850 GLT. I had the same problem two years ago. I bought a replacement from Ebay. It cost me $79 then but is cheaper now. It is a new design to replace the original. The original is made of plastic and aluminum. The aluminum and plastic parts expand and contract at different rates, after some years they seperate. That is why it leaks. The redesigned replacement is made in Estonia. One truly needs a good heater in Estonia, my son lived there for a year.
The new heater gave off a 'new part' smell for about a week, then went away. I have provided the link to the at on Ebay below.
Volvo Heater Core 850 S70 V70 C70 1994 through 2000 MADE IN EUROPE 9144221 NEW | eBay

 

I'm 100% positive it was the foam. When I burnt it with a lighter it smelled exactly the same. And after washing the FCP non-oem one for almost twenty minutes, the smell was just as bad when I re-installed it. I installed the oem core without the foam just in case also and didn't rinse it. The foam may help insulate things, but I don't think it'll make a noticeable difference. If I have a choice between a horrible lung-burning smell or a slightly less efficient heater core, you can bet I'll default on the latter.

So if anyone gets anything out of this thread: IF YOU CHEAP OUT AND GET THE FCP HEATER CORE, DO NOT USE THE FOAM TAPE. IT WILL BURN AND SMELL LIKE BAD WITH A SIDE OF AWFUL. OTHERWISE BUY THE OEM CORE. That mistake cost me almost $250, instead of $150 (Aftermarket core $51, oem coupler $45, oem core $102, another oem coupler (volvo dealer didn't have the o-ring kit, so I had to buy another coupler) $45. And since it's a vital part of your cooling system, I wouldn't get burnt feet and stranded because you tried to save $40. Learn from my mistake.

 

my windows were steaming up on inside with burning smell from vents also a little green puddle on passanger floor board heater core I put a heater/coolant stop leak in there it seemed to work anyone try this yet

 

Stop leak isn't anything new and many thousands of people use it. It's a temporary fix. How temporary ... days, weeks, months maybe even years. It all depends on why it's leaking. If it's rusting or corroding than sooner or later it will rust or corrode around the stop leak material and blow out. If it's a seam between the aluminum and plastic every time the engine runs the materials expand and contract. They will eventually break the seal.

Long story short, sooner or later you need to fix the leak with a replacement part.



Easier to get to the heater core if you remove the front seats too !!
Just kidding.

 

Man, THAT is a cruel photo! That image makes me just a bit uneasy.

Taking the front two seat bolts out make carpet removal a cinch. Really not all that bad if you've got a few hours of daylight to spare.