No Heat!!!!

[SuperHO]

So I was out delivering pizzas tonight.....temp was about 45* with a 10-15mph wind driving a steady heavy rain all damn night, and wouldn't you know it? No heat.

Check a few things...first thing, is it overheating? Guage says no, but it's a stock ford guage....who knows if it works or not? Fans are coming on, but only when sitting at an idle for a few moments...it's normal routine, in other words. Force the idle to drop below 800rpms...no oil pressure light flickering like it would be if it was overheating. In fact, the damn thing's running like a champ. Hop out, open the hood and grab hold of the coolant line from radiator to thermostat....rock hard and not as hot as it should be. Hmm.....odd.....flip the lil lever on the stant radiator cap to relieve pressure...no boiling coolant. So the car's not overheating. But the thermostat wasn't opening. Could be cold ass rain combined with cold ass air combined with lack of A/C Condensor? Dunno....so I yank the thermostat, dunk it in some water and run it halfway through the oven at work. Opens right up. Well shit. Put the thermostat back in and drive home. Check the feed hose when I get home, and it's flaccid and plenty warm....after a 45 minute bounce down the highway, and still NO heat. So....now I'm freezing my ass off, windshield's barely opaque, and I'm getting annoyed. Oh well...time to grab the 98 for a lil bit.

So...is my heater core shit? If so, do I have to remove the entire flippin dash to fix this damn thing??

 

[kzoosho]

To do a heater core yes Tim you have to remove the dash and it aint easy. maybe we can figure it out if yu arent busy this weekend man.

 

[Ishodu]

Blend door or air in the system maybe?

 

[projectSHO89]

Doesn't sound like a heater core.

Check your lower heater hose to see if it collapses when the engine reaches operating temp and the upper hose is hard. If so, your radiator is clogged or your pump has gotten very weak.

Steve

 

[SuperHO]

Boy, wouldn't that be nice?? I've got a brand spankin new waterpump in my back seat as we speak.

However, if that was the case, shouldn't the car be overheating somewhat? The temp guage never rose past 3/8ths the way (about where the top of the "A" is).

 

[MADDOG11]

As stated above I would bet on a control being the problem (ie. blend door/motor, control head, heater control valve).

 

[projectSHO89]

As stated above I would bet on a control being the problem (ie. blend door/motor, control head, heater control valve).

Neither the blend door/motor or the control head can affect the coolant flow through the system.

There is no heater control valve in this system.

**... Check your lower rad hose. Also check both of the coolant lines to the heater core and report back.

Steve

 

[93rev2sev]

Tim, where do you put your pizza's? On the front passenger seat?

I thought that was where the cabin temp sensor was (behind the SHO badge on the dash). If so, is it possible the heat from the pizzas is fooling the sensor?

 

[SuperHO]

Okay...just made a 45 minute highway drive...upper rad hose is again rock hard, engine temp was fine for the whole trip. Lower rad hose isn't collapsed, but the lines going into the firewall behind the engine are only warm from residual heat fromt he engine compartment. They're not hot as though coolant was circulating through them. What would this indicate?

 

[93rev2sev]

Tim, make sure the coolant level in the radiator is ok. Coolant in the overflow bottle will not matter if there is any kind of a leak.

 

[kzoosho]

your coolant lines to your heater core may be blocked.

 

[TimboSHO]

Do you have access to compressed air? Try taking one of the heater hoses off the core and blowing air through it. Or maybe take both hoses off in case you get some crap out of the core

 

[MADDOG11]

Neither the blend door/motor or the control head can affect the coolant flow through the system.

There is no heater control valve in this system.

You are correct about the heater control valve, I forgot.

However, as far as the blend door/motor and the control head both control air flow over the heater core or the evap core. If one of these is intermittantly shorting out or sticking it will cause these problems!!!

 

[projectSHO89]

You are correct about the heater control valve, I forgot.

However, as far as the blend door/motor and the control head both control air flow over the heater core or the evap core. If one of these is intermittantly shorting out or sticking it will cause these problems!!!

Airflow is not at issue here. Read all the symptoms!

This system either has insufficient coolant in it, a restriction, or a faulty pump.

Steve

Steve

 

[MADDOG11]

Airflow is not at issue here. Read all the symptoms!

This system either has insufficient coolant in it, a restriction, or a faulty pump.

Steve

Steve

So if the blend door is stuck and is diverting air over the evap core, instead of the heater core, the air will be hot? HOW IS THAT?? If the blend door will not move over to the heater core side you get cold air! Thus, Airflow is the problem, due to incorrect position of the mode door!

Low coolant, a restriction and/or a faulty WP will also cause overheating. The engine is not overheating as stated in the 1st post!

Why don't YOU READ ALL THE SYMPTOMS!?! I do everyday!

 

[projectSHO89]

So if the blend door is stuck and is diverting air over the evap core, instead of the heater core, the air will be hot? HOW IS THAT?? If the blend door will not move over to the heater core side you get cold air! Thus, Airflow is the problem, due to incorrect position of the mode door!

Low coolant, a restriction and/or a faulty WP will also cause overheating. The engine is not overheating as stated in the 1st post!

Why don't YOU READ ALL THE SYMPTOMS!?! I do everyday!

I can tell you've never been inside this system or, if you have been, you didn't pay attention. Let me educate you.

ALL HVAC airflow ALWAYS passes through the evaporator. The blend door can not affect this as it is AFTER the evaporator.

The blend door allows a portion of the airflow (based on its position) to pass through the heater core to be heated.

I have no interest in engaging you in a pi$$ing contest as we are are all here to help each other, however, I am going to correct obviously inaccurate technical information and will provide the correct information whenever I have it.

Unless the system has corrrect coolant flow, there will be little or no heat. The data provided already indicates the cooling system is NOT working correctly. I can see no logic in overlooking that key prerequisite to focus elsewhere..

Steve

 

[SHOZ123]

Sounds like the heater core is blocked if the coolant level is fine in the engine and the heater hoses are cool (not engine temp) to the touch. Be careful if using air pressure as the core is only normally subjected to 16 lbs of pressure.

I would use a garden hose and be sure to back flush the core going against normal flow.

 

[MADDOG11]

I can tell you've never been inside this system or, if you have been, you didn't pay attention. Let me educate you.

ALL HVAC airflow ALWAYS passes through the evaporator. The blend door can not affect this as it is AFTER the evaporator.

The blend door allows a portion of the airflow (based on its position) to pass through the heater core to be heated.

I have no interest in engaging you in a pi$$ing contest as we are are all here to help each other, however, I am going to correct obviously inaccurate technical information and will provide the correct information whenever I have it.

Unless the system has corrrect coolant flow, there will be little or no heat. The data provided already indicates the cooling system is NOT working correctly. I can see no logic in overlooking that key prerequisite to focus elsewhere..

Steve

Except for 3 heater core replacements that I performed (while asleep) on other's vehicles your right, I've never been into the dash!

"The blend door allows a portion of the airflow (based on its position) to pass through the heater core to be heated." RIGHT!! So if the blend door is not moving (regardless of reason) to allow a portion of the airflow to pass through the heater core to be heated it stands to reason the air will be cold, RIGHT!?!

I'm not trying to get into a ******* match either. It's just that I've seen this exact problem on numerous other vehicles! I find it hard to believe that there is a restriction in the cooling system, low coolant, and/or low coolant flow due to a defective water pump! I am still leaning towards a control issue. As far as a blockage in the heater core, maybe?!? However, a heater core usually blocks up over time not all at once. But maybe?!?

Anyway good luck!

 

[SuperHO]

Okay you two, to your respective corners.

You're both right...however, my issue at this point is seemingly ****** coolant flow, not allowing enough coolant to pass through to the heater core. This is my guess. Sometime next week, I'm gonna tear into it and replace the water pump with a brand new one that's been bouncing around in my trunk. If that don't work, I'll start researching other options. I have no reason to believe that the heater core is blocked, since neither line going TO the heater core gets hot as though coolant was running through it. I just don't think there's enough pressure in the cooling system to get coolant all the way up there. I'm probably gonna replace the thermostat while I'm at it.....really, for no apparent reason. But it's worth a shot.

 

[93rev2sev]

I'm with maddog on the operation of the blend door. HOWEVER: Tim has not yet verified the most obvious, coolant level in the radiator.

It's almost like he's messing with us.
He has a Stant radiator cap with a lever...That's suspect in my opinion.
He lifted the lever to releive pressure...nothing. Even a non overheating car will **** hot coolant on you if you releive the pressure...There IS pressure...the top hose is hard.

If the top hose is hard and nothing comes out of the radiator when you releive pressure, that pressure is steam.

On a cold rainy ass night, the radiator could be nearly empty and still provide enough cooling for the engine...and NO HEAT.

Steam will not open the thermostat all the time. But it will indicate a 212 degree coolant temperature....click ...the fans come on and condense the steam. Temp goes down...still no heat though.