That's certainly suspicious. But their normal failure is that the solder joints crack. You might as well replace it and move on to the next likely culprit. If it hasn't failed, it will fail soon. These things don't have a long life span.

Did you ever determine if the compressor is working?

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe