A friend of mine was helping me replace the expansion valve on my '90 300SL. I don't see how, but he stripped-out one of the bolts securing the valve. We ended up cutting it off with a saw, and as a result there were many small filings in that area of the engine compartment.

I think some filings may have made their way to the evaporator and have considered having it flushed. But when I spoke to a service advisor at the dealership about getting this done, I was told it was not necessary. He explained that any filings would simply pass through the side of the expansion valve that performs no metering and would get caught by the receiver/dryer.

This seems plausible to me. But before I install the new expansion valve, I wanted to ask the experts here what they think: is it okay not to flush the evaporator?