The a/c on my Dad's car has a slow leak that two shops claim to be in the evap. core. Looking at it, it doesn't look too difficult to replace...how hard is it to replace an evap. core in a 1991 190E 2.3?

I would describe myself as an advanced diy'er but I've never done any a/c work. I assume I should have a shop evacuate the R12 and then I can remove/replace the core. I also assume I should replace the receiver/dryer. My main question is how do I determine how much oil to put back into the system?

Anything else I need to be aware of?

Thanks!

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Glen Tokuhara
Beauty & the Beast and the wagon that could!