Heater core replacement



I have a 1987 Volvo 240DL. It has a moving leak of coolant coming from under the dash. My mechanic, whom I trust implicitly, has looked at it at least twice and said he repaired it, but the leak always comes back.

My mechanic says I probably have to replace the heater core and associated hoses, but predicts that it will be costly and risky. Can one take apart the dash on a 22-year-old car and not break something that’s become brittle?

Anyway, I’d like to do it myself. I can get the instructions from All-Data. I’ve got lots of mechanical experience from decades ago when I did all my own auto repairs.

Now I’m 60 years old, but agile and flexible. Is this something I can do? Can the dashboard stand such an insult and retain its viability?


60 is not that old, Look at the instructions as it may also have AC connections. There have been numerous posts recommending ground black pepper that may work or one of the additives as an alternative. How long do you plan on keeping the car?


It’s in good shape and I prefer rear wheel drive and drive less than 3,000 miles a year (I commute by bike), so I intend to keep the car as long as possible and improve it slowly with new paint, etc. I recently replaced the windshield.

My mechanic recommended Bars Leak as a stop-gap that would last three years – but on repeated application would probably last 6 months, after which there would no longer be any choice but replacement.


If you are going to do it, every time that I have to work on around or remove the dash, I remove the front seats of the car. On a that model Volvo it is not hard at all. It will give you more space and it is more comfortable to work.


“My mechanic says I probably have to replace the heater core and associated hoses, but predicts that it will be costly and risky. Can one take apart the dash on a 22-year-old car and not break something that’s become brittle?”

Your mechanic is 100% correct. Heater core replacement can be a NIGHTMARE because it was all junk to begin with. 22 years later, it’s hopeless. Start looking at 2005 and newer and don’t look back. Your mechanic will LOVE you for it…


Wow. If it’s that bad … I don’t want to junk a car because of a minor leak in the coolant system.

No disrespect, but why a NIGHTMARE? If it was all junk to begin with, why did it last 21 years? And even if it is junk, putting new junk in should be fairly straightforward and worth it if I drive it so little.

I’m trying to check out of the fossil fuel transportation system, but my job requires a car sometimes. Taking a chance on new parts seems a bit of a stretch to call a nightmare.


Have you ever replaced a hearer core in ANYTHING, let alone a 20 year old Volvo??


If you check the Haynes manual, you can probably assess the “risk” for yourself. The books are a lot better these days.


I haven’t replaced a heater core in anything.

I have rebuilt a three-speed transmission, two Chevy V-8 engines, a clutch or two and several drum brakes. As I said, I haven’t done anything like this in a long time.

If I have good instructions and new parts, the issue seems to me to be the age of the dashboard. When you called this job a nightmare, what I would like to know is why you put it like that. It’s a substantial comment and I respect it; I’d just like to know more.

Thanks very much.


Thank you. I’ll check in to this.


Are you sure it’s coolant, and not simply condensation? If it smells like coolant, that is certainly bad luck. Volvo 240s are very good cars, but one of their flaws is the heater core, in order to replace it, one must remove the entire dashboard and then some. It takes experienced Volvo techs hours to complete and is a nightmare for the average joe. Take a look at the All-Data instructions, and you’ll see the job at hand. You can certainly tackle it if you should choose to do so, but you’ll likely need an entire day to do it and if you spread the job out, another car to drive when you’re not working on it. Here are some photos from a fellow Volvo enthusiast: http://cleanflametrap.com/heater_core/

Remember, you can always loop a heater hose from the cylinder head to the pipe that comes off the water pump and use one of those portable heaters that plugs into the 12v socket in the cab, that’ll save you a lot of grief.


Those are some great pictures on the previous post link, so if your car is any where close to the same model year as in those pics, you have a great reference available. I would certainly attempt it. You’ve been warned by all the negative posters, so if you have the time and energy, go for it. When you’re putting it back together, I’d for sure have lots of electrical tape and insulating material (foam, etc) so you can tape everything in place, because you’re bound to discover new squeaks and rattles when your done if not careful about insulating everything. The best part of doing this yourslef is the pride after a job well done.


Maybe this will help.


I don’t see why you can’t do this job. Heck, I just turned cough 60 according to my wife but in reality I’m 21 and I work on cars all of the time including the hot rod variety.


I’d say give it a go. If it has to be done, just don’t break anyting taking it apart, take a few pictures on disassembly, take your time and have fun. I did a few . . . are tough, others are really easy. The heater core on my old '79 Dodge pickup could . . I swear . . . be done in less than a half hour. Everything is out in the open with lots of room. Just have at it and take your time. I’m 52 and I’d try it. Rocketman


Dave; I’m sure with patience you can do the job. We have had 3 heater core replacements over the years; on a 1971 Mercury Comet 6 without air, a 1976 Ford Granada V8 with air and a 1984 Impala V8 with air.

All were difficult, but the Granada was a nightmare, according to my mechanic, who also replaced the Impala’s core ($225 in 1994). On the Granada it seems the core was placed in the car and the whole dashboard and controls then built around it. It took 8-10 hours of labor, and my mechanic told me to go elswhere if it happened again.

If your car has no air conditioning, the job will be easier. But you may learn a whole new X-rated vocabulary because of the car’s age.