Join Date: Nov 2012
Location: Western CT
Car: 1999 Legacy Outback, bone-stock.
Feedback Score: 0 reviews
HG Leak stops coolant circulation?
Will exhaust pressure from HG failure stop coolant from circulating?
1999 Legacy Outback, auto, power everything websites seem to indicate it has a EJ25D motor (not sure where to check on the vehicle), just bought under 2 months ago. Friend who sold it to me had timing belt & water pump done at time of sale (I thought the mechanic he used was a $&^*). I've gone 5k since, totaling 155K.
Last night within sight of my house, suddenly noticed cold air from heater. Looked at temp gauge and it was pinned to H. Pulled into driveway and shut down, opened hood. Radiator cap not especially hot, nor top rad. hose. Overflow bottle looked full but brownish in the flashlight beam. No cottage cheese on dipstick or oil filler.
This AM called in sick due to car, started to read up on the topic, HG seemed likely. Opened radiator on cold engine, added about a pint of water (figured no matter what, would be dumping it soon) until it was full. Started engine, hoping to see it puke out a burst hose or cracked radiator, no luck. Idled about 15 minutes with defroster on, temp gauge came up to middle but never saw flow in radiator neck. Burped a small bubble about once a minute. Got worried that if coolant wasn't circulating, temp in heads might be extreme, shut down engine.
Called friend in California who is Honda/Chevy "A" tech. He suggested maybe stuck thermostat. Called local Subaru dealer, talked to service desk. The guy there said that no cottage cheese in oil is normal Subaru HG fail mode, bubbles in coolant were sure sign of exhaust in coolant, and the part I found odd: He said that the exhaust pressure in the coolant was sufficient to prevent circulation???