I'm getting tired - Heater Core Leaking

[SanCarlosQ45]

Hey everyone. For about the past two years my heater system has had air in it causing the typical gurgle noise right after startup. Now what I have noticed is a bubbling or air escaping noise from the dash right after I shut off the engine. I think this maybe due to the expansion of the coolant right after shut down.

Anyways I spent my sunday tearing apart a junkyard 94' (picknpull south san jose) to get at this:

Back side towards firewall


Front towards interior







I have to say I would not want to do this job until it is absolutely necessary. There are so many different fasteners for every piece behind the dash and you have to pull the 2" bar that runs across the dash. You will also need the security torx T50 bit because you have to pull the entire airbag system including the control unit by the shifter. I can see why people abandon these cars if something like the heater core goes because it is one of the worst jobs you could possibly do in this car. I can see a minimum of 4 hours to tear the interior apart doing it carefully; I did it with my dad in 2.5 hours but we cut most of the harnesses and broke some piece of the dash because we couldnt tilt the the steering column.

Luckily I only paid $18 for the entire heater box which is nice as I dont know exactly what is leaking, most likely the heater core as nothing is coming into the interior. I will be doing this job this summer and from there I will see if I really want to keep this car or not. I never thought I would think of getting rid of it but it needs a transmission and the engine could use a replacement; very noisy cold running, maybe valve train noise. I am loosing coolent somewhere, I'm just hoping it just heater core and not head gasket related.

For now I will take some Copper elbows and bypass the heater core until I fix it. When I do I will have to take pictures so this may make a good guide for the future.

[N/A Q45]

My best guess is if the inside of the car under the heater core isn't wet and you can't smell coolant then the heater core isn't leaking-

If I were you I would check your rad/coolant caps to make sure they do not leak.

Just because you hear bubbles in the heater core doesn't mean it is leaking/ just means there is air in the system that is going to the highest point.

Try parking the car on a really steep hill, use your ebrake for safety or try and get the front end up on ramps/ jacked up with the car cool so you don't burn yourself start the car, turn heater on max and see how much if any air pockets come out of the system.

Usually the most common causes from what I have delt with on cars is start buy checking any rad or system caps, coolant incase there is gas/oil in it, water pump for leaking, exhaust incase it is burning it/spark plugs = (bad head gasket). There are also lots of little coolant lines around the TB that could have a small crack.

[SanCarlosQ45]

I'm getting coolant smell from the ducts as well as some fogging on the windshield occasionally. Rad cap is new as well as thermostat and rad hoses; radiator was replaced at some point. Nothing is visibly leaking, I do need to check the hose at the throttle body as I did pull it out when I removed the throttle body. The problem is every time I drive it which is about once a week, I have to fill up the overflow a little. No puddles overnight.

I used the lisle funnel that attaches to the filler neck to bleed the system, but a couple days after it returned to its normal self.

[N/A Q45]

Well you could be smelling it just from it coming out of the engine bay and sucked into the cabin. The last resort would be to replace that heater core. But you say fogging on the windsheild, do you think that could be just from a temp difference in the car vs outside temp. You should be able to see some kind of moisture dripping off the heater somewhere if you remove the panel below the glove box when it cools. But you should try/check what I said earlier then go from there.

[GeraldP]

Hi All,

Where is the core located exactly? To the left of the fan and AC Cooling Unit? Does Dash have to come completely out or can it just be loosened?

Does anyone know of a diagram or a video anywhere about this?

Thanks !!!

Gerald
601-503-8234
[email protected]