Before you replace the evaporator, I'd replace ALL the o-rings in all the fittings and on the expansion valve. o-rings soaked in mineral oil and then exposed to R143a seem to rapidly become rock hard and leak, often slowly enough there is little or no oil trace, but you will slowly loose charge AND eat the compressor from the water that leaks in.
There are quite a few -- one large one on each end of the compressor hose set, 5 or seven on the condenser and receiver/dryer, and four on the expansion valve. All the liquid side ones are the same size, I think, and MUST fit into the fitting easily -- the usual assorment has quite a few that are too large although they fit the hose well, and they cut and leak. Peter _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com