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how hot is your heat???


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The subaru cores are about the same as their radiators. It's a two-row unit, about 8" by 6", with metal tanks. The problem is that back flushing them really does no good at all because the inlet and outlet tubes are about 4" apart on the same tank. The pressure just runs right out the other side, or forces the gunk farther into the core....

 

I guess I'll have to take a picture cause clearly none of you people have seen one. :rolleyes:

 

GD

 

I have to disagree. I have never had one apart, but there has to be a divider in the header tank. if not, the hot coolant would go right out and there would be no flow in the core and it would act like a clogged core all the time. At first the core would be full of hot coolant, but the fan would quickly remove that heat and the output would be barely warm. In the picture posted above, you can see the crimp or divider.

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I have to disagree. I have never had one apart, but there has to be a divider in the header tank. if not, the hot coolant would go right out and there would be no flow in the core and it would act like a clogged core all the time. At first the core would be full of hot coolant, but the fan would quickly remove that heat and the output would be barely warm. In the picture posted above, you can see the crimp or divider.

 

Yeah - that's a good point. I hadn't noticed that. Guess I was too busy trying to get the new core in with this freezing rain :mad:

 

So it looks like the coolant is forced through half the core, around the bend on the other tank, then through the other half, and back out. So back flushing might do some good. Still need a LOT of pressure as those small tubes are going to turn your spray into a lot of little..... thinking about hooking up my pressure washer, and feeding it with the hot water tank in the garage :)

 

GD

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There is no control valve on EA82's. Your core is probably partially clogged. Sadly there's really no good way to fix them as the inlet and outlet pipe of the core are on the same side and close together. Forcing high pressure water into the core will just shove stuff further into it. Replacement is the best option - cores aren't expesive, and installation takes about 6 hours total.

 

Thermostat's almost always fail closed and cause too much heat. If your guage reads about 1/3 up it's plenty hot if your core is working properly.

 

GD

Darn.... cause my friend's new EA82 never gets above cool (compared to icy cold if it's off). I was hoping we could pressure out the core, but It seems that they're prety hard to clean huh. I've sold subaru's before because the heater core was clogged, rather than replacing it because it's such a pain to get to (okay, it also had alot of other stuff wrong, but that was part of it)

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Darn.... cause my friend's new EA82 never gets above cool (compared to icy cold if it's off). I was hoping we could pressure out the core, but It seems that they're prety hard to clean huh. I've sold subaru's before because the heater core was clogged, rather than replacing it because it's such a pain to get to (okay, it also had alot of other stuff wrong, but that was part of it)

 

It's not that bad - about 6 hour total. I just did the one on my Sedan. I took parts of two days to do it as I went to the home cheapo and got some auto/marine grade weather stripping and replaced the foam on some of the ducting. It's actually nice to clean all the duct work anyway - I cleaned everything with pine-sol, and removed even more mouse nest over in the drivers side fresh air intake. It's nice to not have ANY piss smell at all. Smells like a clean car inside now.

 

GD

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same problem same car. exactly! just face it we can all buy new heater cores togeather. I hate putting them in and since I did 3 all my frends are like man lets call jess hes goood. grrrrrrrrr and I have to do one more. Granted ive never done one on a roo.... any pointers or any thing wierd, so I dont break anything??? thanks Jess

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I just fixed a cold heater in my Brat....there was a large duct between the blower and the center consul which had sagged and shrunk, allowing the warm air to disburse rather than come through the vents. I don't understand why the car wasn't still getting warm, since theoretically the heat was escaping INTO the cab...but maybe the incoming air pressure created by driving 70 MPH was pushing cold air into the system through the vents without the fan's back pressure to keep it out....all i know is, after a 10 minute fix, the brat is now totally hot within a few minutes.

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a couple of weeks ago when the temps dipped to -20 , i put some card board in front of the radiator and also took my grille off and covered it with aluminum foil.. which it nice cause i can draw on it with a sharpie and make it like a vanity plate... it just adds to the trashiness .. what a difference it made! now im plenty toasty on my way to work in the a.m. although.. i leave it on defrog all the time because i dont like the warm air blowing in my face and i hate frogged up windows. o.k... now for the point of all my ranting.. why does the defrogger feel and sound like it blows harder at idle than it does under accelleration? kinda odd i thought.. but its my first soob

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now for the point of all my ranting.. why does the defrogger feel and sound like it blows harder at idle than it does under accelleration? kinda odd i thought.. but its my first soob

 

Because the doors that direct the flow are vacuum controlled, and under hard accelleration, the vacuum produced by the engine is not sufficient to keep them in the defrog position, and they spring back to the bilev position which is the default with no vaccuum. That's how both my EA82's have been -- if I go up a steep hill the defrogger switches back to the bilev vents (which don't make as much noise on the same blower speed). I suspect that you could fix up the old vacuum system to keep this from happening, unless it happened even with new ones.

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that has got to be the quickest response to any question ive ever had! even my wife doesnt answer me that quick when i have dumb questions... hahaha... thanks plenty.. i suppose i can live with it like it is.its only six months a year that i have to listen to it anyways:D

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Would blocking the radiator help???

 

If the temperature gauge shows normal engine temperature, no. It would increase the risk of overheating. Very bad. If the engine temperature is below normal, get a new thermostat.

 

 

 

This reminds me of a mod I do on my EA82s. There is a vacuum actuator that opens a flap door to draw outside air for the heating system. The only setting that does not use outside air is AC MAX. I added a switch and a vacuum solenoid to allow my choice of recirculated or outside air in all modes. It allows you to get more warmth while the engine is getting up to temperature. Also, if your'e leaking oil on the manifold, you don't have to smell it so much.:grin:

 

It would improve heat output, since the reciculated air is not as cold as the out side air.

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would the out side temps mess with my thermostat? It works fine in less it is around 20 degrees or less.

 

If the temperature gauge shows normal engine temperature, no. It would increase the risk of overheating. Very bad. If the engine temperature is below normal, get a new thermostat.

 

 

 

This reminds me of a mod I do on my EA82s. There is a vacuum actuator that opens a flap door to draw outside air for the heating system. The only setting that does not use outside air is AC MAX. I added a switch and a vacuum solenoid to allow my choice of recirculated or outside air in all modes. It allows you to get more warmth while the engine is getting up to temperature. Also, if your'e leaking oil on the manifold, you don't have to smell it so much.:grin:

 

It would improve heat output, since the reciculated air is not as cold as the out side air.

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would the out side temps mess with my thermostat? It works fine in less it is around 20 degrees or less.

 

The thermostat is the thing that controls the temperature of the engine. Only indirectly effects the heater. The engine is supposed to be about 190 degrees F. I have noticed that very cold (like under 20F) will keep the engine slightly cooler than on a 70-80 degree day. Like a needle width or so. I don't think that difference would be terrible noticable in the heater output - by feel.

 

If the engine thermostat is stuck open, the engine will not get up to operating temperature. This causes higher fuel use because the ECU will be running rich to make the engine run smooth while still cold. If it is run rich enough, long enough, it could eventually kill the catalytic converter.

 

There is no thermostat in the heater control system. All 4 EA82 4x4 wagons I have owned had good heat. Sure, it takes a little longer to warm up in very cold weather.

 

In the morning here, I start the car, drive downhill top the highway. A little over 2 miles. By 1-1/2 I can get silghtly less cold *recirculated* air on blower speed 1 or 2. Once I am up the ramp, switch to speed 4. Once I get warm, switch to fresh air, slower blower speed. Not scientific - I never had reason to take readings, etc.

 

BTW starting from a garage at 40 F makes a huge improvement in the warm up of the inside of the car time.

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The thermostat is the thing that controls the temperature of the engine. Only indirectly effects the heater. The engine is supposed to be about 190 degrees F. I have noticed that very cold (like under 20F) will keep the engine slightly cooler than on a 70-80 degree day. Like a needle width or so. I don't think that difference would be terrible noticable in the heater output - by feel.

 

If the engine thermostat is stuck open, the engine will not get up to operating temperature. This causes higher fuel use because the ECU will be running rich to make the engine run smooth while still cold. If it is run rich enough, long enough, it could eventually kill the catalytic converter.

 

There is no thermostat in the heater control system. All 4 EA82 4x4 wagons I have owned had good heat. Sure, it takes a little longer to warm up in very cold weather.

 

In the morning here, I start the car, drive downhill top the highway. A little over 2 miles. By 1-1/2 I can get silghtly less cold *recirculated* air on blower speed 1 or 2. Once I am up the ramp, switch to speed 4. Once I get warm, switch to fresh air, slower blower speed. Not scientific - I never had reason to take readings, etc.

 

BTW starting from a garage at 40 F makes a huge improvement in the warm up of the inside of the car time.

 

well without a functioning thermostat you have no heat.

 

i did find on my 87 that if it was below 20 outside (before global warming in NY) and i let the car warm up in the driveway, i could keep up with the cold air. If i just drove off it was hard to get the car toasty.

 

nipper

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I had previously mentioned a cold heat as well... after acknowledging the heater core now gets warm for reasons I am not sure of, it is clean, thermostat is good , fluid is good.. I ended up with hot heat for reasons I didn't intend .

It was one or all of the following:

  • I found an oem flaw in the coolant reservoir and swapped it for good one- the cap did not have proper threads to tighten (I am meaning to get a photo of this... kinda like an upside down printed stamp, but less valuable :grin: )
  • I did an engine flush per instructions on the fluid jug
  • I removed EGR flow (very noticable)
  • cleaned out heater box area, and yet have to blow needled air through core
  • lubed heater motor, cleaned years old mouse guts out. :slobber:
  • Removed "ASV" and made the hose to plenum another heat riser (a driver side one!)
  • Removed Anit-backfire valve ( I am assuming this did nothing to help heat- but I can't say for certain)
  • I found a tint of the rustoleum primer I used in the wiper linkage bay on the heater core! (oops- it sucked some vapors in and lightly painted itself):rolleyes:

The heat is as hot as my spfi soob (that was a roaster), but air is not as powerful, that would be my prob after working with heater engine.

Some things to do to keep permanently warmer heat-

  • a quick shot of paint acceptable for the clean heater core
  • Target engine flows, A boxer (especially cool carbed) will actually refuse heater core flow if engine flow is very strong..it wants down and out like a hot rod :confused: , find a way to make "fluid bouyancy" change to at least the level of heater lines (add top end heat riser, or take away).
  • Explain this all to GD in his language :)

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Explain this all to GD in his language :)

 

GD's language (I know the guy pretty well...) is english. From what I can tell, your's appears to be gibberish (much like chinese, I know it when I see it, but still can't understand it). And as far as I know you are the only one here fluent in early 21st century stupid, so who's going to translate eh? :)

 

GD

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