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hi, i posted another day about my overheating engine, put in simply, it idles fine, but won't go more than 1/2 mile before temp gauge climbs to top

 

i had car towed back home yesterday, and turned on heater full blast while it overheats, there is no heat!!

 

there is no loss of coolant, i can not spot any leaks, and there is no water in engine oil, so i rule out any leaks or head gasket problem, top radiator hose does not feel very hot even though it is overheating on the temp guage

 

my question: is the thermosat in the heater loop? i am trying to isolate if this is a water pump problem or a stuck thermosat

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It's not in the heater loop but affects that loop also as tunered said. Sounds like a blockage or lack of circulation for some reason. The thermostat is the eaiest place to start. Remove it and see if problem persists. While you have the thermostat out take of the rad cap (Before it gets warm.) and see if there is circulation in the radiator. If you have circulation then the water pump is working. If not, water pump is not working or you have some kind of blockage preventing circulation.

Had a night mare of a problem with my 90 Legacy.:confused: Two used and two new thermostats and still it over heated with a thermostat in but no problem with it out. Ended up modifying one of the new one's to get the problem resolved. :)

my question: is the thermosat in the heater loop? i am trying to isolate if this is a water pump problem or a stuck thermosat

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just took out the thermostat, and broke one of the 10mm bolts, any body has extracted this before, it seems pretty small, last time i tried drilling on such small bolt i ended up damaging the metal threads surrounding the bolt

 

If the bolt broke as you were taking it out then there is probably a problem right there. Personally, I would find it easier to just replace the water pump at this juncture, thereby eliminating two possable problems at once. What part of CA are you in again?

Send me a PM if you are within 100Mi of SF or Sac, and want me to do the work. Unless the timing belt is fairly new, I would replace it at the same time so you know it has been done. I can do both parts at the same time, or you can.

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hi, i posted another day about my overheating engine, put in simply, it idles fine, but won't go more than 1/2 mile before temp gauge climbs to top

 

i had car towed back home yesterday, and turned on heater full blast while it overheats, there is no heat!!

 

there is no loss of coolant, i can not spot any leaks, and there is no water in engine oil, so i rule out any leaks or head gasket problem, top radiator hose does not feel very hot even though it is overheating on the temp guage

 

my question: is the thermosat in the heater loop? i am trying to isolate if this is a water pump problem or a stuck thermosat

 

These car's tends to overheat of there is "no flow" situation in the heater-core water lines (trapped air situation).

First, disconnect the water hoses of the heater in the engine bay and pump water to one of them untill clean water comes from the other water line.

 

Connect the water hoses of the heater to thire original location and check the fluid level in the radiator (fill up in necessery).

Start the engine and check for overheat. If its still overheat, check the thermostate and water-pemp.

 

(Once i had a incident with an Impreza that started to overheat after disconnecting the heater-core water lines. The mechanic did a bypass with a hose that didnt allow the water to flow. I disassembled the hose and connect another hose that allow the water to flow as usuall. The car never overheated since).

 

Itzik

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I wouldn't spend money and labor on the water pump and belt until I rule out the head gasket. I think the head gasket is blown. The classic 2.2 HG falure is betwen the water jacket and the cylinder, there will be no water in the oil or vise-versa. The engine overheats before the thermostat even gets the hot water to open it. The temp gauge is on top where it is hot and the thermostat is on the bottom where it is still cool. Start the car and look into the overflow bottle, do you see bubbles?

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I wouldn't spend money and labor on the water pump and belt until I rule out the head gasket. I think the head gasket is blown. The classic 2.2 HG falure is betwen the water jacket and the cylinder, there will be no water in the oil or vise-versa. The engine overheats before the thermostat even gets the hot water to open it. The temp gauge is on top where it is hot and the thermostat is on the bottom where it is still cool. Start the car and look into the overflow bottle, do you see bubbles?

 

I recomended the T-belt and pump because he has a bolt broken off inside the old one, and it is a lot easier to replace it than it is to extract the bolt. the pump is cheap enough that replacing it is a reasonable thing to do in this case.

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I was thinking that if it was a HG or a cracked head, is it worth fixing? If the body and the rest of the car is good I would find a low milage replacement motor. Hummm...now you got me thinking....if you do put in a low milage replacement motor I would change the water pump and belt anyway....disregared my last post.....(unless your car is rusted out or on it's last legs)

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thank you for all the tips, it's been great learning from you guys

 

i am in bay area, but the impreza originated in Vermont/ NY area until 2003, so there are a lot of surface rusts in the engine bay, not only i broke the bolt, i had a hard time taking off the old-style (not stainless steel) radiator clamps so i just sniped them off

 

actually after i broke the bolt, i went to Kragen and got a thermostat, went home and boiled the new and the old one, both opened at the the same time, so i kind of ruled out the thermostat there, next i put back the thermostat housing with one bolt and held the other end with a vise grip, started the engine idling and again no heat from the heater even without thermostat, barring a clogged heater, it indicated the coolant was not flowing so right there i suspected the water pump not doing its job, it's not the radiator because the heater would still blow hot, it's not head gasket because if it were the HG the heater would still blow hot air (unless heater is clogged), i had no coolant leak and the heater air was not even warm, so i spent the whole afternoon getting to the water pump, it turned out it was seized, i could not turn it with my bare hand, now i have couple of questions:

 

1) how do you push the tension adjustor rod ? Legacy777's manual says you need a press, i don't have a press, how you guys do it? i have a vise, but the manual says no vise

 

2) how do you torque the crank pulley nut to some 120 ft/lb?

 

3) i hope i have solved the overheat problem, but is the head gasket damaged by any chance? it was staying at the redline for no more than 10 seconds before i pulled over and shut off engine in several occasions as i was trying to reach my destination couple days ago

 

thanks again

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thank you for all the tips, it's been great learning from you guys

 

i am in bay area, but the impreza originated in Vermont/ NY area until 2003, so there are a lot of surface rusts in the engine bay, not only i broke the bolt, i had a hard time taking off the old-style (not stainless steel) radiator clamps so i just sniped them off

 

actually after i broke the bolt, i went to Kragen and got a thermostat, went home and boiled the new and the old one, both opened at the the same time, so i kind of ruled out the thermostat there, next i put back the thermostat housing with one bolt and held the other end with a vise grip, started the engine idling and again no heat from the heater even without thermostat, barring a clogged heater, it indicated the coolant was not flowing so right there i suspected the water pump not doing its job, it's not the radiator because the heater would still blow hot, it's not head gasket because if it were the HG the heater would still blow hot air (unless heater is clogged), i had no coolant leak and the heater air was not even warm, so i spent the whole afternoon getting to the water pump, it turned out it was seized, i could not turn it with my bare hand, now i have couple of questions:

 

1) how do you push the tension adjustor rod ? Legacy777's manual says you need a press, i don't have a press, how you guys do it? i have a vise, but the manual says no vise

 

2) how do you torque the crank pulley nut to some 120 ft/lb?

 

3) i hope i have solved the overheat problem, but is the head gasket damaged by any chance? it was staying at the redline for no more than 10 seconds before i pulled over and shut off engine in several occasions as i was trying to reach my destination couple days ago

 

thanks again

 

1) I used a vice, go slow, put a little alan wrench it the hole to keep it compressed.

2) There is an access hole (with a black rubber plug) to the flywheel. It is located behind the intake manifold. Slide a large screwdriver down into it to stop the flywheel from turning.

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thank you for all the tips, it's been great learning from you guys

 

i am in bay area, but the impreza originated in Vermont/ NY area until 2003, so there are a lot of surface rusts in the engine bay, not only i broke the bolt, i had a hard time taking off the old-style (not stainless steel) radiator clamps so i just sniped them off

 

actually after i broke the bolt, i went to Kragen and got a thermostat, went home and boiled the new and the old one, both opened at the the same time, so i kind of ruled out the thermostat there, next i put back the thermostat housing with one bolt and held the other end with a vise grip, started the engine idling and again no heat from the heater even without thermostat, barring a clogged heater, it indicated the coolant was not flowing so right there i suspected the water pump not doing its job, it's not the radiator because the heater would still blow hot, it's not head gasket because if it were the HG the heater would still blow hot air (unless heater is clogged), i had no coolant leak and the heater air was not even warm, so i spent the whole afternoon getting to the water pump, it turned out it was seized, i could not turn it with my bare hand, now i have couple of questions:

 

1) how do you push the tension adjustor rod ? Legacy777's manual says you need a press, i don't have a press, how you guys do it? i have a vise, but the manual says no vise

 

2) how do you torque the crank pulley nut to some 120 ft/lb?

 

3) i hope i have solved the overheat problem, but is the head gasket damaged by any chance? it was staying at the redline for no more than 10 seconds before i pulled over and shut off engine in several occasions as i was trying to reach my destination couple days ago

 

thanks again

 

OK, I have the tools for this, if you want me to help. Give me a PM, or an email, and I'll give you a phone number to call to set up a time. Oh, and some things you should only use Genuine Subaru parts for. The Thermostat is one of them. While you are in there, a front crank seal and the O-ring ro the oil pump would be a good idea (this will keep you from having to go in there again). I'm pretty sure I have those parts as spares, though.

(to send a private message or email, click on my name, and a page will come up with my info on it)

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