2004 SUBARU LEGACY OVERHEATING
REPLACED HEAD GASKETS 2013, IST OVERHEATING IN JAN 2014, 2ND OVERHEATING DEC 2016 AND 3RD OVERHEATING 2/17. REPLACED THERMOSTATS X2 AND NEW RADIATOR 12/16. MECHANIC CAN'T DUPLICATE THE OVERHEATING WITH DRIVING AND LETTING CAR IDLE
Intermittent problems are difficult to solve. What sort of driving conditions cause the over heating? Did your mechanic check the cooling fans?
I've run into a couple of similar post-hg-replacement scenarios. First involved a simple clogged radiator; the second clogged rear heater hoses. Flush both and clean rad to see if better. Also, a non-OEM (smaller) t-stat will cause overheating as its bore is too small. So check that t-stat is OE.
I have changed my head gasket twice in nine months, the last about 2 months ago and the car still overheats anytime I drive over 60 miles. The fans are in good condition
Re-read previous post.