Blend door on chevy suburban

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AaronW

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hey everyone, I'm kinda out of ideas on my suburban heater.

I got my arm in there to the blend door actuator, and I can feel it turning, when I turn the heat/cold know of the dash. No clicks that should be there, and I would hear something if the actuator was turning but the blend door wasn't moving, correct?

It's got a brand new thermostat the end engine is coming up to temp.

It's got a brand new heater core.

What else is there? The hoses going into and out of the heater core feel warm. If the water pump were bad, it would be overheating, right?

I'm out of ideas. Any of you think of something I could be missing?

Aaron
 

bucket

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The heater hoses just feel warm, not hot? Are the heater hoses anywhere near as hot as the radiator hoses? Is the heat blowing out of the dash anywhere near as warm as the heater hoses?
 

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What blend door did you check? There are 2. Does cold side seem to work?
 

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The heater hoses just feel warm, not hot? Are the heater hoses anywhere near as hot as the radiator hoses? Is the heat blowing out of the dash anywhere near as warm as the heater hoses?

Just warm, not hot. When I checked, I was running a little below the 210 mark on my dash gauge, so it did seem like they should be hotter than that. That's what got me to wondering if my water pump wasn't puming hard enough through the hoses, but then, it seems like I should be running too hot, right?

What blend door did you check? There are 2. Does cold side seem to work?

I checked the one inside the center of the dash; the one that's real hard to get to, where you remove the glove compartment and go in towards the center of the dash. When you say the cold side, the AC works, if that's what you mean. I stuck my finger on the front of the actuator, and could feel the little white plastic part that sticks out of it turning when I changed the dash dial.

Aaron
 

squaredeal91

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Just warm, not hot. When I checked, I was running a little below the 210 mark on my dash gauge, so it did seem like they should be hotter than that. That's what got me to wondering if my water pump wasn't puming hard enough through the hoses, but then, it seems like I should be running too hot, right?



I checked the one inside the center of the dash; the one that's real hard to get to, where you remove the glove compartment and go in towards the center of the dash. When you say the cold side, the AC works, if that's what you mean. I stuck my finger on the front of the actuator, and could feel the little white plastic part that sticks out of it turning when I changed the dash dial.

Aaron
The other one is by your right leg. driver side. It's easy to see on my 99 Burban. I'm not exactly what that one does. But it might change from hot to cold. I remember replacing the hard one a long time ago, I think it controlled defrost to vents maybe.
 

AaronW

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The other one is by your right leg. driver side. It's easy to see on my 99 Burban. I'm not exactly what that one does. But it might change from hot to cold. I remember replacing the hard one a long time ago, I think it controlled defrost to vents maybe.
Yeah, I've seen youtube videos on that one too. I think that's the "mode door" actuator for changing between defrost, to the floor, and so on.

Aaron
 

rusted nuts

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Could be outlet from water pump to heater hose full of rust or at return hose and block or intake..
 

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squaredeal91

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just because that little thing turns don't mean it's turning it on the other end. Sometimes they just strip out. might just have to take it apart and see. Seems like you've checked most everything else.
 

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bucket

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Just warm, not hot. When I checked, I was running a little below the 210 mark on my dash gauge, so it did seem like they should be hotter than that. That's what got me to wondering if my water pump wasn't puming hard enough through the hoses, but then, it seems like I should be running too hot, right?



I checked the one inside the center of the dash; the one that's real hard to get to, where you remove the glove compartment and go in towards the center of the dash. When you say the cold side, the AC works, if that's what you mean. I stuck my finger on the front of the actuator, and could feel the little white plastic part that sticks out of it turning when I changed the dash dial.

Aaron

It doesn't matter too much what the factory gauge says. Do the radiator hoses get significantly hotter than the heater hoses? Does the heat out the dash feel somewhat similar to the temp of the heater hoses?

The answers to those two questions will tell you what needs investigating.
 

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