Here’s a new thread for you all to argue over….
After some 14 years and 1500 hours of near faultless running, the Volvo 2020D in my B32 Another Fantasy recently developed a problem. Although the engine ran fautlessly without overheating or any other signs of distress, it refused to pump coolant throught the hot water calorifier circuit. Despite all the obvious checks: fresh water circulation pump, thermostat, heat exchanger, header tank, heat exchanger pressure cap etc etc, nothing seemed to be amiss. In despair I consulted the local Volvo Penta agent who, after going over everything with me, had a ‘Eureka’ moment. He asked me what kind of anti-freeze I had been using. Answer: various different brands over the years, BlueCol, Shell, BP, Halfords, Starbrite, whatever came to hand. It never occurred to me that they could have different chemical formulations; I thought anti-freeze was basically different pretty coloured versions of methyl (or ethyl) alcohol. Not so, the man said. Some have very different formulations and in some cases, when mixed with other brands will react and form a glutinous gel. Without actually identifying the culprits we dismantled the entire calorifier pipework system, flushed several times with a chemical cleansing agent and then refilled the system with the naturally very expensive Volvo equivalent. Result: problem solved. Moral: mix anti-freeze brands at your peril, blockages can be difficult to clear!!
Ian Culley
B32 Another Fantasy