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1979 300SD Diesel Heating Solution

Hello,

I have a 1979 300SD 5 cylinder diesel in awesome shape. I just started having a heating problem and I had the cracked thermostat replaced. Last summer the thermostat ran at about 40-50c and now its running at

90 degrees.

The fan in front of the radiator isn't coming on. The air conditioning blast out cold and the heat blasts out heat.

Is the fan supposed to run at all times? If yes, what should we be looking for as the cause for the fan not running?

I am also looking for a mechanic in the east end of Toronto.

Thanks Judy

Reply to
classicone
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Your running temp of 90 is normal. The aux fan is supposed to come on when AC is on... check the fuse first.

Reply to
Tiger

The electric fan in front of the radiator, a/k/a auxiliary fan, runs on demand. The important thing is that the engine temperature be at 80+ degrees C, rising to say, 100 degrees C, when pulling up long grades. Incidently, the device you called the "cracked thermostat" is the much cursed climate control "servo".

I've owned an '80 300SD since new and agree it's a fine car. Mine now has a digital retrofit climate control system in place of the "servo" etc. - my concession to technology.

Reply to
-->> T.G. Lambach

On May 15, 12:35 pm, "-->> T.G. Lambach

Reply to
trader4

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