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Very little heat in my EA81


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The blower works okay, not much air gets pushed on high setting, but I'm sure a better alternator or new motor will work.

 

The real problem is my heat is barley warm at normal speeds, but if I am slow going or at a light, the heat seems a bit warmer. It corresponds with the engine temp. Do I have super awesome cooling to where my engine doesn't get hot enough to provide good heat? My temp needle hardly moves too much past cold unless I am in traffic or at a light.

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For starts, if you don't get much air at high speed, sounds like the first thing to do is:

 

pull the blower motor, and clean out the junk between it and the condensor/heater core. I bet it is packed of crud and nesting.

 

Then, would be to flush the heater core, and while you are flusing that out, you can pull the thermostat (if there is even one in there), go ahead and buy a OEM new one from the Subaru dealer, do not use autozone, advance, napa etc, use only OEM.

 

Then yo should be in better shape with heat.

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Yeah I'm sure it could use a cleaning out. I have to park under one of those dumb trees with the little tiny leaves. My car gets covered daily when they fall.

 

The blower motor, would I have to take off the whole dash to get to it? I see where it sits on the passenger side.

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Yeah I'm sure it could use a cleaning out. I have to park under one of those dumb trees with the little tiny leaves. My car gets covered daily when they fall.

 

The blower motor, would I have to take off the whole dash to get to it? I see where it sits on the passenger side.

 

You just have to take off the wall/tray thing under the glove box, and then take out the glove box itself to get at the top bolts to the blower assy.

:burnout:

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Best way I found to flush a heater core is to get one of these garden hose repair ends.

 

TG23437_143029

 

Put it on your garden hose, put the unit in and alternate between the return hoses.

 

I have seem that trick to flush the coolant. I am in an apartment unfortunately, so I will have to head out to my dad's shop to attempt that.

 

So If I don't have a thermostat, wouldn't I have hot air by default? Unless my understanding of the thermostat is to allow cooler water into the block at a certain water temp is wrong.

 

First easiest step is to clean out the blower. Still no better heat, take a look at the thermostat. What are signs of a bad thermostat?

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The heater core bypasses the thermostat and runs directly from the water pump. If there is no thermostat, and the engine is not all the way warm, the heat is not all the way warm.

 

What is your temp gauge doing?

 

You are assuming the car will run hotter with no thermostat, but the opposite is true, as the engine will run too cool. The thermostat holds back coolant around the engine, and when it gets too warm, some of that moves to the radiator to cool enough and then it closes. It does this cyclically to maintain a steady temp of about 190 deg.

 

If there is no thermostat, all of the coolant is going through the radiator, and at highway speed, the radiator is continuing to cool the coolant beyond the point that a thermostat would have closed oce it cooled back down to the desired temp.

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What is your temp gauge doing?

 

 

It sits just above the cold mark. like an 1/8th tank on the gas guage. then if I'm stoped it slowly crawls to about 1/3rd.

 

 

You are assuming the car will run hotter with no thermostat, but the opposite is true, as the engine will run too cool. The thermostat holds back coolant around the engine, and when it gets too warm, some of that moves to the radiator to cool enough and then it closes. It does this cyclically to maintain a steady temp of about 190 deg.

 

If there is no thermostat, all of the coolant is going through the radiator, and at highway speed, the radiator is continuing to cool the coolant beyond the point that a thermostat would have closed oce it cooled back down to the desired temp.

 

 

That makes sense. If I am on the freeway at all, I'm doing 70. So sounds like the thermostat is the suspect. I'll pop that out and take a look. I'm sure I will just replace it anyways, they are not that expensive.

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my vote already is the thermostat is MIA, and it is clogged with nesting between the blower motor and the heater core. especially evaporator if the vehicle has or had AC.

 

I do have dealer installed AC (i think its dealer that puts it out to the side of the engine where factory puts it in). I need to get a dry day here and start cleaning stuff out.

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You need to verify your operating temp - the dash gauge is a waste of time. Use an infra-red temp gun or a k-type thermo-couple if you have a meter that can register one.

 

The operating temp of the engine should be between 180 and 220* F. If it's not - start with the thermostat - get one from the dealer along with the gasket. If it is - most likely you have a clogged or partially clogged heater core and/or debris in the blower motor housing. The leaves you park under are not likely to be the culprit - the baffles that keep water out also keep out virtually all of the junk as well.

 

It's all pretty simple and scientific - you do some tests with a temp meter and then you make the neccesary adjustments.

 

GD

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