On the Ignition Tumbler I am for pulling it once every1-2 years and popping it in the Ultrasonic Tank I have. And I had been doing that except.

Alternatively once it is out you can spay anything in or on the out side of it that does not eat up pot metal and hose it out with compressed air.

I wonder if the door locks could be hosed out with some cleaner and then some compressed air shot in through the slot to blow out any accumulated crud. I have not read of anyone doing that.

If it were my Car I would be curious to see if putting some tape over the Key hole when you get home at night keeps water out. An easy cheap experiment.

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84 300D, 82 Volvo 244Gl Diesel