Subraru Overheating

subaru
legacy
suspension

#1

My son’s turn of the century Subaru Legacy Outback what overheating here in Spokane a month ago when it was in single digit temperatures for a few days. He put a couple of quarts of coolant in, which was a slow process. He put in a new thermostat suspecting a problem there. A couple of days later he was on the freeway and overheated again. He stopped and pulled off the radiator cap. There was a fountain of cold coolant. He suspected a blown head gasket. We have removed his engine and drained the oil. Oil looks good with no obvious coolant in it. He can blow through the radiator without a pressure buildup. The water pump bearings seem good. Before pulling the head and going through all that we are wondering if we are missing something. Any advice would be appreciated.


#2

Are you sure the water pump is good? Is there flow? A leak down test on the cylinders would prove it.


#3

If the car overheated and the radiator had cold coolant in it, than the coolant is not circulating. Unless he installed the T-stat backwards, than either the water pump has failed totally (I’ve never seen one fail totally) or there’s a blockage, perhaps a collapsed inner hose liner. This I HAVE seen. And since it was a “slow process” adding a couple of quarts of coolant, which should have taken less than a minute, I STRONGLY suspect a blockage.

Just because the water pump bearings seem good does not mean the impellars are not worn to a nub.

And I would not remove the heads until I did a pressure leakdown test on the cylinders. If you have no leakage, the headgaskets are not blown and removing the heads can only add to your problems.


#4

Wow ! From over heating straight to pulling the engine. That’s ambition.


#5

I am a little concerned by the phrase 'put a couple of quarts of coolant in it"

I know you don’t get a lot of really cold temps in Seattle and I wonder when, if ever, the strength of the coolant was checked.

If the radiator had ice in it , this could happen.


#6

Thanks all. PvtPublic, he wanted to replace the clutch anyway.


#7

Ah yes. New clutch and head gaskets. Shop would charge $$ to do that work. More than car is worth.