It's possible I've got a leak in the heater core. Symptoms: an odd smell when the heater's on, and the windshield fogs up pretty dramatically when I try to defrost it (eventually, it clears, but it takes time).

I've read through the remove-replace instructions, and it looks doable. But is there a way to check for a leak before I take it all apart?

If you have green antifreeze, fog up the windshield, run your finger through the fog and taste it - if it is sweet, you have a leak.

If tasting is offensive to you, wipe some of the fog into a small rag, and have an assistant smell the rag before they go near the car. Fog from plain water should have no aroma.

The sweet taste is why you should keep antifreeze away from small animals, including children.

You can still drive the car with the under dash panel and kick panel removed from the driver's side. Keep them in the trunk or garage. Removing the panels will let you see the rubber floor mat and see if there is anything leaking on the mat. If it is already leaking a lot, check the antifreeze level immediately. If you don't see any leaks with a cold engine, run the engine and take a peek for steam.

There are some nice cheap units on Ebay.
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Keeping it running is better than buying new

It's not an awful repair undertaking but may be a little messy if it's been leaking for a while. Just did it on my '95 and the carpets and insulation were soaked.

But I disagree with KlausC (rarely!).
I would only purchase one from a verifiable reputable seller.
Some part suppliers even offer a lifetime guarantee.

To me, it was worth the extra $ compared to a "cheap" eBay part.

Hello All,

I can only speak from my own experience. A few years ago, I ordered an after market heater core from a company that specializes in Volvo parts. I don’t recall if it was listed on Ebay or Amazon. However, the company that sold this unit, said its construction was superior to the Volvo or OEM supplied heater core. In particular I recall it used a different manufacturing process/materials (?) at the top of the heater core, where on the Volvo/OEM unit you had plastic and aluminum joined together. This company’s argument was this design was flawed because you joined together two different materials (plastic and aluminum) which had different rates of heat expansion and therefore were guaranteed to leak.

I ordered this unit because it was significantly cheaper (I thing it was $40). After I installed it, the heater core gave off an obnoxious and irritating odor. I contacted the manufacturer and explained my experience. It refunded my money and issued me a free return postage sticker to send the core back before is issued a refund.

I then went out and purchased an OEM heater core (I believe the company that manufactures them is called “”Behr” - I think they are made in France?). I installed the OEM unit and have had not problems what so ever. Of course, I know someday, it will fail again. By the way, the symptoms you described, I too experienced before I replaced the heater core. The real evidence was that the rug on the driver’s side was wet with coolant.

Anyway, looking back, I tried to save a significant sum of money. Instead, I wound up having to replace the heater core 4 times: once to remove the old one, once to install the new “bargain” core, again to removed the “bargain” core, and finally to install the OEM core. At least I got “pretty good” at replacing the heater core.

I tried to save money when servicing my cars, but in this case, and again, I am only speaking from my experience, I would have best been served by using the OEM heater core from the start. My 2 cents.

Hugh

Hi Hugh,

FWIW - I put a Behr radiator into my 95 850 6 years ago. Zero problems... I went with a Behr because I was concerned about buying a Nissens radiator as I had read on the RWD forum about problems with them. Behr is a quality company, German based. A lot of the OEM parts in our Volvos are sourced from Germany. Which I think is a good thing (in most cases)!!

Damn, my 850 now needs a heater core! Oh, well...

Jim

For less than $40 and free shipping plus a "life time" guarantee? Why not? Beats FCP any day.

But, Ebay purchases require due diligence on behalf of the buyer. Study the picture carefully and find out where it ships from. Return postage is probably not worth the aggravation.
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Keeping it running is better than buying new

Mine made the driver's side a carpet very oily mess. The job is a little bit of a pain due to under dash cramped fiddling, but very doable money & saving.