HELP...Overheating issue!

ratso · 12-14-2008, 01:00 PM

97 Legacy GT, 2.5L, pure stock (the wife's car). 146,000 miles. Yesterday it overheated after a 5 minute drive. I noticed the car had no heat, was blowing cold air. Boiled over about 2 minutes later.
Has full level of fluid, I pulled the T-stat thinking it was stuck. Put it in a pot of water on the stove with a thermometer. Started opening at around 170, full open at 190. Changed it anyway. Still have tyhe same issue!
Fired it up this morning, it is about 35 degrees outside. Temp gauge was coming up, but still had no heat. Scan tool hooked up says the coolant was at 235. Then heat came on for a while, temp gauge cam down to normal level, then blew cool again and temp gauge went high. Upper hose (return) is very hot. The lower hose going from radiator to T-stat is always cold. What gives? The water pump is about 2 years old and has 15,000 on it. When I had the stat out, I looked up in the water pump opening and saw the impeller. Looked OK. It spins when the motor is cranked over. It runs off of the timing belt, correct? So it is not like it can't be spinning. What would make the heat in the car go from real hot to cool air and the overheat the motor?

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piperpilot26 · 12-14-2008, 02:00 PM

hmm...I was just going to say to try the water pump, but if the impeller looks good then I would have to say the t stat. make sure its in correctly.. but if its not either then Im stumped.

ratso · 12-14-2008, 02:38 PM

Yep, stat is in the right way. Tried burping the system, no good. Noticed a few air bubbles in the overflow/resorvoir. Does that mean head gasket?

So I drained it all again and drilled two 1/8" holes in the T-stat face in case there was air pockets being caused by a blown head gasket. Now it runs fine. Bottom hose is hot now, but there are much more bubbles in the resorvoir. Car has heat now also, so I guess it has a blown head gasket and the trapped air/gases would not let my pump flow? Drilled holes gave it a path to excape? Other than seeing bubbles in the overflow tank, I would have no idea it has a problem.

3rdgearpinned · 12-25-2008, 04:12 PM

so you determined it has a blown head gasket? my car is having similar problems.

Where did you drill the holes exactly?

mattmcnew · 12-26-2008, 06:08 AM

Bubbles in the coolant overflow tend to mean a blown headgasket,I would know because my car definitely has one,and it does that.

It also tends to blow all the coolant out of the radiator when i go WOT =[.

ratso · 12-29-2008, 05:37 PM

Quote:

Originally Posted by 3rdgearpinned

so you determined it has a blown head gasket? my car is having similar problems.

Where did you drill the holes exactly?

I drilled two 1/8" holes in the face of the T-stat so water can flow through it when it is still cold/closed. Olny a temporary solution because it takes forever to warm up now and still blows exhaust into the coolant. Only a matter of time before it gets worse. At least the car is driveable until I get a new one.

blackfang · 12-29-2008, 05:53 PM

I would not rule out blown headgaskets.

Turn in Concepts · 12-29-2008, 05:56 PM

Quote:

Originally Posted by ratso

I drilled two 1/8" holes in the face of the T-stat so water can flow through it when it is still cold/closed. Olny a temporary solution because it takes forever to warm up now and still blows exhaust into the coolant. Only a matter of time before it gets worse. At least the car is driveable until I get a new one.

your head gasket. it's no longer gasketing...

mike 53 · 01-03-2009, 10:19 PM

Just a quick word on that blown head gasket . Your description does indicate a blown gasket but it is very close to a blocked heater core also . I recommend trying it out with the heater core bypassed as a last resort before changing HGs It would be a shame if that was all it was
The conditions inside the water pump with a swirl of different temperatures means that the only way to check a subaru thermostat is to replace with a genuine one Mike

a1killer · 01-03-2009, 10:40 PM

like everyone has said it could be the t-stat the pump or the heater core or you could have some scales in your fluid. You should check your fluid maybe even change it, check your heater core and or change it out or check your head gasket and replace it.

12-14-2008, 01:00 PM	#1
ratso Scooby Newbie Member#: 119458 Join Date: Jul 2006 Location: Nazareth, PA	HELP...Overheating issue! 97 Legacy GT, 2.5L, pure stock (the wife's car). 146,000 miles. Yesterday it overheated after a 5 minute drive. I noticed the car had no heat, was blowing cold air. Boiled over about 2 minutes later. Has full level of fluid, I pulled the T-stat thinking it was stuck. Put it in a pot of water on the stove with a thermometer. Started opening at around 170, full open at 190. Changed it anyway. Still have tyhe same issue! Fired it up this morning, it is about 35 degrees outside. Temp gauge was coming up, but still had no heat. Scan tool hooked up says the coolant was at 235. Then heat came on for a while, temp gauge cam down to normal level, then blew cool again and temp gauge went high. Upper hose (return) is very hot. The lower hose going from radiator to T-stat is always cold. What gives? The water pump is about 2 years old and has 15,000 on it. When I had the stat out, I looked up in the water pump opening and saw the impeller. Looked OK. It spins when the motor is cranked over. It runs off of the timing belt, correct? So it is not like it can't be spinning. What would make the heat in the car go from real hot to cool air and the overheat the motor? * Registered users of the site do not see these ads.

01-03-2009, 10:19 PM	#9
mike 53 Scooby Newbie Member#: 199107 Join Date: Jan 2009	Don't put it on the stove Just a quick word on that blown head gasket . Your description does indicate a blown gasket but it is very close to a blocked heater core also . I recommend trying it out with the heater core bypassed as a last resort before changing HGs It would be a shame if that was all it was The conditions inside the water pump with a swirl of different temperatures means that the only way to check a subaru thermostat is to replace with a genuine one Mike

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12-14-2008, 02:00 PM	#2
piperpilot26 Scooby Newbie Member#: 197453 Join Date: Dec 2008	hmm...I was just going to say to try the water pump, but if the impeller looks good then I would have to say the t stat. make sure its in correctly.. but if its not either then Im stumped.

12-14-2008, 02:38 PM	#3
ratso Scooby Newbie Member#: 119458 Join Date: Jul 2006 Location: Nazareth, PA	Yep, stat is in the right way. Tried burping the system, no good. Noticed a few air bubbles in the overflow/resorvoir. Does that mean head gasket? So I drained it all again and drilled two 1/8" holes in the T-stat face in case there was air pockets being caused by a blown head gasket. Now it runs fine. Bottom hose is hot now, but there are much more bubbles in the resorvoir. Car has heat now also, so I guess it has a blown head gasket and the trapped air/gases would not let my pump flow? Drilled holes gave it a path to excape? Other than seeing bubbles in the overflow tank, I would have no idea it has a problem.

12-25-2008, 04:12 PM	#4
3rdgearpinned Scooby Newbie Member#: 131664 Join Date: Nov 2006	so you determined it has a blown head gasket? my car is having similar problems. Where did you drill the holes exactly?

12-26-2008, 06:08 AM	#5
mattmcnew Scooby Newbie Member#: 147134 Join Date: Apr 2007 Chapter/Region: South East Location: Tampa,Florida Vehicle: 2003 Subaru WRX WRB	Bubbles in the coolant overflow tend to mean a blown headgasket,I would know because my car definitely has one,and it does that. It also tends to blow all the coolant out of the radiator when i go WOT =[.

12-29-2008, 05:53 PM	#7
blackfang Scooby Specialist Member#: 131347 Join Date: Nov 2006 Chapter/Region: MAIC Location: Richmond Va Vehicle: 2007 Legacy 2.5i SE 98 Z/28, VN 900 custom	I would not rule out blown headgaskets.

01-03-2009, 10:40 PM	#10
a1killer Scooby Newbie Member#: 100097 Join Date: Nov 2005 Chapter/Region: NWIC Location: Morton Washington Vehicle: 06 impreza 2.5i SMG/brown	like everyone has said it could be the t-stat the pump or the heater core or you could have some scales in your fluid. You should check your fluid maybe even change it, check your heater core and or change it out or check your head gasket and replace it.