Non valk- no heat- GM

[fudgie]

Kits got a 2001 Chevy S-10 Blazer. I get no heat. Fan works. Changed the thermostat last night. Old one was defintly sticking. Still no heat. I'm thinking heater core but with my old truck I still had heat when it went out. So I have no idea. Whatta you think?

[Smokinjoe-VRCCDS#0005]

I'm no mechanic but with my wife's car and over $1,500 in parts on it in the last month or so I'm becoming one with each passing day     I'd bet heater core as well but everyone I've seen that was bad leaked     Just a thought does it have a shut-off on the heater hose line ? Some folks install those to help the A/C cool better in the summer....You did make sure it's full of coolant ?  On my Dodge 4X4 I flushed and re-filled and it was amazing how much better the heater worked.

[Hef]

I'm with Joe on this one. If it's not low on coolant I would bet on it being the heater core. Try the backflush before replacing.

[longrider]

In my experience in 2001 GM used three electric actuators to move the doors, one for each of these modes, cold to hot,  floor/defrost, recirculate.   I suspect the one that moves the cold/hot door is not working.  They are usually around $50 or so.  can be a pain to install as they are attached to the heater box.  I've had to replace one on my 01 gmc 2500 and also my 01 pontiac grand prix

warren

[R J]

Fudgie, just go buy her a Dodge Dakota and junk the Chevy.

You have to pull the firkin dash to repair that beech.   It ain't no fun, trust me.

Another thing you can do is disconnect both heater hoses and then put water through one of the outlets to see if it will let water flow, then try it on the other outlet.   NO flow, core is plugged or even if it is a dribble, it is plugged.

PS:    Make sure ya get the damn hose back on the right outlet.  If ya don't it won't work also. Don't ask how I know this........

[Jabba]

I'd bet with Longrider. 

Does it BLOW wind?  and it's not hot?

How long have you had the chevy?  Is the heater core bypassed?

try the flush out too.  I have seen them be REALLY bad.

Jabba

[Mondo Limbo]

You didn't say whether or not you have A/C.  On most vehicles I've seen with no A/C, there is a shutoff valve somewhere along the heater hose, usually under the hood.  Turning the heat off closes the valve, turning it on opens it.  If that's the case, yours may be stuck or the actuating system isn't working.

[MAD6Gun]

 Brian> GM had a problem with heater cores getting plugged in those trucks. Do this first. Start the engine and get it up to temp. Touch the heater hoses at the core. Both hoses should be close to the same temp. If one is much cooler than the other the core is plugged. You can remove the hoses and flush the core with a garden hose. I have good luck doing this. If this is the case flush the core and than perform a coolant flush on the truck. If debree is stuck in the bottom of the block it will get into the core and plug it again.....
  RJ is right about them being a bitch to replace. You have to remove the dash to get at it. But if memory serves me right you have to do the same thing to service a Dodge core.
 If the hoses are both hot than the problem may be the temp door actuator in the dash as was stated earlier. I hope this helps.........

[fudgie]

Well the more I think about it, and the GM guy agreed, it maybe the temp selector switch. The dial has degree settings 65-85 deg. The other day she couldnt get it to work. She stopped by and had the settings wrong. When I did it, it blew out warm air. Now it just blows air. GM guy said he would change the temp selector switch. Thats a $400 item. I do have a $100 deductable for the warrenty but its a hassel taking in it. It only has 75k on it and was old guy owned. Coolant was done in 04. Off coarse it has the GM Dex-cool so it should be good for 100k.  When she gets home I'll run the a/c and adjust the temp range to see if it gets warmer or cooler.

Your right Joe, all the ones I replaced were leaking.

RJ, Kit is from a Dodge family. But no way would I own one.  GM all the way. 

Never heard of GM having shut offs/bypasses. I've owned/family had 78, 85, 89, 94, 01, 04 trucks and never seen any. I know some of our ambulances do but never at the engine side. It usually at the ambulance box so we can switch from heat to a/c.

[fudgie]

Brian> GM had a problem with heater cores getting plugged in those trucks. Do this first. Start the engine and get it up to temp. Touch the heater hoses at the core. Both hoses should be close to the same temp. If one is much cooler than the other the core is plugged. You can remove the hoses and flush the core with a garden hose. I have good luck doing this. If this is the case flush the core and than perform a coolant flush on the truck. If debree is stuck in the bottom of the block it will get into the core and plug it again.....
  RJ is right about them being a bitch to replace. You have to remove the dash to get at it. But if memory serves me right you have to do the same thing to service a Dodge core.
 If the hoses are both hot than the problem may be the temp door actuator in the dash as was stated earlier. I hope this helps.........

Thx Mark will do. 

[fudgie]

Mad6Guns was right. The out going hose was cooler. Back flushed it into one of my funnels that has a screen and it was loaded with grap. Good size chunks to, about 10 of them 1/4" in size. Now its like a oven in there. Thats all. I owe ya Mark. 

[VegasF6]

I woulda bet for sure it was the blend door. Wrong again.