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HEAT? Noooooooooooo!


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Hi Group,

 

My 92 loyale has been having this problem off & on since October and I though we fixed it. I was wrong. Now that there's finally snow in NYS the heater doesn’t work so good.

 

THE PROBLEM

The air blowing out the heater is no warmer than your breath.

 

 

THINGS I HAVE TIRED:

 

* Changed thermostats 2X with new 195 deg units.

 

* Flushed the heater core 3X

 

* Visually inspected all vacuum hoses, and watched operation of all actuators and levers

 

* Checked heater control cable, travel of control arms and general movements of parts

 

* Blocked off ½ of radiator to restrict airflow

 

* Tried to bleed air from heater core by jacking up front of car and running engine till warm with radiator cap off.

 

ALSO...

 

* The engine comes up to proper operating temp (about 1/3 to 1/2 way on dash gauge)

 

* The lines to and from the heater core get hot

 

The ONLY thing that is consistent when the heat gets luke-warm is that I can HEAR air bubbling though the heater core under hard acceleration. This same problem happened a year ago... so I had the local oil-change place change the radiator fluid with their power-flush system, which seemed to get the air out. The heat worked fine last year.

 

 

QUESTIONS:

 

* Could air in the heater core be the causing of the problem?

 

* Will a radiator flush under pressure (<5 psi) help?

 

 

I don’t mind bundling up to drive, but it’s not good for my 5 year old.

 

Any help would be greatly appreciated!

 

:santa:

T.J.

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Whot's the outside temps like? You have to factor in the fresh air intake from the blower houseing. If the outside air is like 20, and the heater is at 120, then the air coming out of the vent's is going to be a lot lower. I pulled the vacume controls that hold open the fresh air openeing to the blower housing on my car, and welded it shut on the Brat (it's another place for water to come in). Without the colder air feedin the heater, then the air will get warmer and warmer untill it's good an hot in the car. I'm used to workin on EA81 cars, and not sure how the blower is set up on the EA82's, but I imagine it's not that different.

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T.J. sure sounds like an embolism to me.

The core locks an air pocket in itself as it sits a bit higher than all other coolant system components.

The "burping" I have used involves removing the output hose from the core. This is the hose on the left as you face the firewall, it is NOT the hose connected to the pipe running under the intake manifold. This pipe comes from the H20 pump and is the input to the core.

Temporarilly plug the place where the hose connects to the block. Place the open hose end in a jar or catch can and start the engine. When a staedy stream of coolant comes out, thumb plug the hose and reconnect it quickly to the proper fitting. Messy but has never failed to release a trapped air pocket.

 

Note on EA82 cars there is NO coolant flow control valve, as there IS on EA81's, all temp control is done via a "blend door" in the ventilation system.

The gurggling sound is the tip off to an embolism.

Hope this helps

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TJ hope you catch this before starting the project.

If you do not get pressure out of the hose you have disconnected please try the other hose.

I have been informed that there were some changes made to the newer models, my experience is with earlier ones. Sorry for the confusion.

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Well... I just finished Skip’s procedure for bleeding the air out of the heater core. Here's what I did...

 

1. Elevated the front of the car on ramps

2. Disconnected the outlet hose from the heater core and attached a hose so it could discharge back into the radiator.

3. Corked the inlet hose/pipe back to the engine.

4. Ran the car for 2 minutes until it was a little warm.

 

As I watched the fluid pump out of the heater core and back into the radiator it was a steady stream of coolant with only a few little hick-ups.

 

After I drive the car tonight I will report back with the results.

Hopefully I won't have to bundle up like old St. Nick when I drive!

 

 

:santa:

T.J.

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TJ, did the gruggling sound stop?

If not you may have had the wrong hose disconnected.

 

On the blend door, this is a swinging gate affair that directs the air either through the heater core or around it.

Best thing I can tell you to do is get on your knees, say a small prayer j/k

Look up under the dash at the HIVAC unit and move the hot/cold lever.

This is one part of the ventilation system that is manual not vacuum controled.

The hot/cold lever is attached to a cable which in turn is attached to the blend door bell crank. Moving the lever should result in the door moving, sounds like possibly the cable loop has jumped off the door accuator, ie bell crank.

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The "gurgle" sound is almost totally gone... however I can still hear a "whoosh" noise (the sound of flowing water) under hard acceleration.

 

As for disconnecting the hose, I know I got the correct one as it has an arrow on in indicating the water flow. I used the one with the arrow pointing towards the front of the car. Thus, the water was pumped out.

 

 

Also... I looked under the dash at the movement of the mechanisms that are controlled by the heater cable. The plastic gears and crank appear to be moving correctly and seem to slide to their maximum extension in both directions. I can also head the door open and close with a hollow plastic "thud" sound, when it is all the way towards hot or cold.

 

Am I missing something?

Can this unit be taken apart?

Could something be broken inside?

 

 

:confused:

T.J.

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TJ, there should be no sounds if all the air is out of the core

The gurgle is a sign of some still trapped.

May be time for the power flush again, sorry.

 

as for

 

Am I missing something?

I sure can't think of anything except the above

 

Can this unit be taken apart?

It's a real PITA to get the HIVAC out

 

Could something be broken inside?

I guess the blend door could be broken, but you say you can hear it move and close.

 

 

Try running in AC MAX after unplugging the AC compressor clutch - atleast the outside air will not be entering.

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One other thing to try before ripping into the dash. This has worked on some vehicles, some it didn't.

Disconnect both heater hoses and swap their positions, start/drive car for a few. Then replace the hoses as normal.

This will reverse the flow thru the heater core, and flush out some of the stuff that likes to collect in there.

Like I said, doesn't always work, depends on how the core, and it's supply tubes are related to everything else.

Do you have a good flow of air thru the vents, at all positions? Could have a mouse nest blocking off some of the ductwork.

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you should be able to pick up a flush/fill kit from any auto parts place. They usually have several T-fittings for various size hoses, and usually include the hose clamps for installing the T.

The last one I purchased (several years ago) also had a spout thing that was supposed to go in the radiator filler neck to direct the flow out when you hooked up a wter hose to flsh the system.

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As I mentioned in another thread, I just removed the belt-driven fan as it's clutch is bad the fan never stopped turning, thus making the engine too cool.

 

Funny thing is... the engine still dosen't get too hot. I let it idel for 15 minutes and the thermostat only went to the 1/2 mark. I drove it down the express way and the guage dropped down to the 1/3 mark.

 

It acts like a VW beetle engine, like it's supposed to be air-cooled!

 

 

As for the inside heat... it is a little better but not by much.

 

I also disconnected the AC pump. That also helps a little.

 

I will try the reverse hoses trick to back-flush the heater core and check for leaves, etc. tomorrow.

 

 

:santa:

T.J.

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No leaves and back flushed the heater core... very little improvement on the Heat.

 

Belt driven fan has been gone for 2 days and the car has yet to over heat or even go past the 1/2 way on the thermostat.

 

I am making a "T" connector / air bleeder out of copper pipe and some valves. I'll try it this weekend if it dosen't improve.

 

T.J.

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