1991 Legacy AWD Automatic

About 1000 miles ago I noticed the tell-tale coolant drip from the Water pump weep hole. Before the recent battle under the hood the temp gauge never went above 3 o'clock, didn't matter if the heat was on or off, driving up a hill, down a hill, high speed on freeway, or stop and go city traffic.

I Lurked on this board looking for recommendations. I Ordered the T-Belt Water pump kit from Mizumoauto, t-stat, picked up new plugs and wires, new air filter, oil filter and oil, and the accessory belts.

 

Jumped in changing the cam seals, crank seal, water pump, t-stat, T-belt, the idler pulleys, tensioner bearing, the plugs and wires, oil and filter, accessory belts, and burped and filled the cooling system.

 

Drove around town short trips no issues, felt comfortable driving the 25 miles to work. After driving for about 15 miles all freeway with no traffic, I noticed the temp start rising above the normal 3 o'clock position. I flipped the heat to high and turned the fan on high, the temp returned back to normal position. Turn heat and fan off and temp starts rising again. The air blows like a blast furnace.

 

Things I have checked:

Coolant bottle when I get to work is slightly above the full mark.

Coolant bottle when I get off 12 hours later is between the fill and full marks.

Checked the Radiator and the level is full, squeezing the upper radiator hose doesn't produce any air bubbles.

No oil residue inside coolant bottle.

No latte colored oil.

 

My understanding is since the heat works most likely not and air bubble trapped in a pressurized system. No oily residue or latte colored oil indicates no blown head gasket.

 

My guess is faulty T-stat, but wanted to seek help/advise before I drain the system and put the old t-stat back in. I just replaced it due to convenience since I had it out and thought to save myself work later if it went bad.

 

I searched and came up empty with similar issues, so any help would be appreciated.

 

TIA,

Mike:-\

Did you use an actual Subaru (OEM) t-stat?

Its the aftermarket thermostat. they don't open enough

 

here is a pic of the one to my GL which did the same thing (guess which one is dealer and which is "duralast, motorad" etc. made in Israel junk

 

---------------------------AWESOME-----------------------------------------JUNK----------------

 

Edited February 22, 201115 yr by Ricearu

look at you beating me to it! lol

 

just buy a new one from the dealer, mine cost me $18. well worth it in my opinion.

replace the radiator cap too while you are at it.

replace the radiator cap too while you are at it.

 

+1

 

A faulty radiator cap will have you scratching your head for a long time.

I heartily concur with yer diagnosis doctors. I did that exact operation just yesterday on the 2.2 that I slapped into my 98 OBW. The temp just wouldn't stay put without the heater on. I operated by bloodletting and doing an exploratory. As expected it turned into a Durastatectomy. I replaced it with the OEM one that was in my 2.5 and burped it according to Dr. Nipper. The patient recovered immediately and now purrs like a kitten.

Dead-Last T-stat is out when I get home from work in the AM, well I will let it cool down first. How convenient one dealership in town is 6 blocks from work, the other 1 mile from home. Good to know I was headed in the right direction, I kept thinking to myself they look so different, and double and even triple checked the part numbers online to make sure before I installed it.

 

Thanks for helping out.

 

BTW

Still running strong at 350K+ miles. Next goal 500K

Great to hear. I can not tell you how many times I have saw posts where those parts store thermostats cause a world of problems to people's cars.

YAY we love simple issues. Still replace the cap just because. Get one at parts store unless the dealers is cheap.

Yeah, replaced the T-stat last week and the issue is officially closed, no more running hot. Thanks to all those that replied so promptly.

Awesome man. Keep that thing on the road.