The heater core may be leaking. The smell of coolant mix and also tell take of a leaking heater is wet carpeting either side, usually the passenger side footwell floor carpet more so. First smells of coolant and then a mildewy mouldy and worse odor. Coolant allowed to set is corrosive. The coolant if left under the US market driver side carpet can migrate rearward and pool at the lowest point in the floor pan. Rust can form.

The two short heater hoses between the engine and the heater core tubes that sick out through the firewall bulkhead should be accessible for a tool to loosen and tighten the hose clamps. A hose clamp if not properly tightened can come loose. If your motor mounts are old, the engine sags rearwards making access more difficult. The K-Jetronic intake manifold makes it the effort a bother versus the smaller LH-Jet manifold.

Do not use your 1979 244 DL with low coolant else the light aluminum alloy cylinder head will warp and the head gasket can fail. New coolant should be the green or blue antifreeze and at least distilled water. You may want to inspect hoses and the water pump and the radiator. In the radiator if old coolant persistes, mineral deposits form from the bottom upward. With radiator removed inspect the large lower port (cooled coolant return output back to the water pump).

From your many posts your 300k 1979 244, with Bosch K-Jet / Electronic Ignition, suggests high mileage and some neglect. Depending on region if the rust belt or dry or snow and salt free climes can suggests items to look for.

You have abundant YouTube videos, the 700-900 FAQ here for systems the 700-900 series shares with your 1979 244 sedan like the engine coolant subsystem.

You can read the many posts here on your brickboard about the engine cooling and the heater and what to look for and how to treat it.

The Bentley manual is best for 240. Haynes is a second. Clymer / Chilton a distant third or more. You can find factory service manuals scanned to PDF on the OZ Volvo Technical archive (https://ozvolvo.org/archive/) and elsewhere.

Our Art Benstein and other folks have an article here that contains errata notes for the Bentley manual.

Also, Art's cleanflametrap.com site is an invaluable great work for the Volvo 240 owner. Art has like an armada of ten 240s.

The anecdotal information here on your brickboard is now an unconscious collective of Volvo issues and resolutions. And a great examples of how Amazon Web Services (AWS) may be used as with biopharmaceutical discover and informatics for the heavy computation list AWS provides health sciences.

It would help if you could upload images to the Brick Pix photo gallery and link them in a RWD post article and allow us to look at your 240 and suggest some items. Emphasis on the engine bay and underside with some exterior and interior images. Or post to a photo hosting site and past the link in your message. (Not photobucket!)

I've had four 1970s 240s. Two were 1979 with M46 manual gearbox. Missing the 1979 242 GT now. US midwest rust ate it.



Hope that hepkats (helps).

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