Heater core removal

[D'arce]

That’s exactly what was going on with mine. I had a lot of leaking in the footwell and engine bay was dry. My heater core was corroded and leaking into the heater box and into the footwell

Ok thanks. I'll loop around the core for now and get one on the way. Fun times ahead lol.

 

[T4R2014]

I'm just here to laugh at the guy who thinks green coolant killed his engine.

 

[DrivertheHiker]

Troubleshooting this coolant leak

Hi, I'm new here (and to car maintenance generally), recently picked up a '96 V6 SR5 with 257K miles. Yesterday I replaced the valve cover gaskets to fix an oil leak and today I started leaking coolant from the passenger side firewall. I just ran it for 5 minutes in the driveway with the AC on and the puddle was significant; pretty disheartening. So my questions for the more knowledgeable and experienced...

1) Before I buy a new heater core and take the whole dashboard off, is there any chance it's something a little simpler like a loose connection?

2) Any way to just get through the glove box to have a look without taking everything apart?

3) Did I screw something up during the gasket job or is this just a bad coincidence?

 

[Skulking]

Hi, I'm new here (and to car maintenance generally), recently picked up a '96 V6 SR5 with 257K miles. Yesterday I replaced the valve cover gaskets to fix an oil leak and today I started leaking coolant from the passenger side firewall. I just ran it for 5 minutes in the driveway with the AC on and the puddle was significant; pretty disheartening. So my questions for the more knowledgeable and experienced...

1) Before I buy a new heater core and take the whole dashboard off, is there any chance it's something a little simpler like a loose connection?

2) Any way to just get through the glove box to have a look without taking everything apart?

3) Did I screw something up during the gasket job or is this just a bad coincidence?

Are you sure it is actually coolant that is leaking? Passenger side firewall is where the AC drain line comes out and it just drips to the ground from there.

 

[DrivertheHiker]

Are you sure it is actually coolant that is leaking? Passenger side firewall is where the AC drain line comes out and it just drips to the ground from there.

Now I'm embarrassed, I think maybe it is condensation. I just put a paper towel under the leak and let it run for a few minutes. No greenish color on the paper towel at all. I left this out of my first post for brevity but I took it to get inspected this morning after finishing my gasket job, but it didn't pass for unrelated reasons (steering rack bushings, lower ball joint, front brake lines - I have more fun ahead) but the mechanic mentioned I had a pretty bad coolant leak, which was news to me. I assumed he knew better than I would, so I believed him.

Can I test the heater core by idling the car and running the heat? This would not create condensation but would cause the core to leak if it had one, yes?

 

[thegipper]

Are you actually losing any coolant (check the reservoir, is it low)? If so, there are several heater hoses on the back of the engine by the firewall and they can leak (mine did).

When the mechanic said you had a bad coolant leak, did he say where it was leaking from?

 

[Bad Luck]

Now I'm embarrassed, I think maybe it is condensation. I just put a paper towel under the leak and let it run for a few minutes. No greenish color on the paper towel at all. I left this out of my first post for brevity but I took it to get inspected this morning after finishing my gasket job, but it didn't pass for unrelated reasons (steering rack bushings, lower ball joint, front brake lines - I have more fun ahead) but the mechanic mentioned I had a pretty bad coolant leak, which was news to me. I assumed he knew better than I would, so I believed him.

Can I test the heater core by idling the car and running the heat? This would not create condensation but would cause the core to leak if it had one, yes?

Turn the heat on and make sure the ac compressor is turned off. If the leak is only present with the ac on then you most likely have the ac drain tube clogged. It's on the firewall below where the ac lines go into the firewall. Stick a piece of wire or a small stick into the drain and wiggle it around. If that's your problem then some water should come out if you have your ac running. It's amazing what a spider web can stop lol

 

[01thunder]

Correction.

I address TWO things in this thread.

First : Heater Core removal
I installed a NEW HEATER CORE into my car "sprinter" made by Toyota, but wanted to show the world how to do it. I chose a 4runner for that purpose.

Second: For older cars (except Limited models, thanks for pointing this out)

IF your AC is low or having hot air when you select outside air (cold mode), try this:

The hot coolant shut off valve will leak. Even a 97 4runner with 180 K miles will leak (I checked 2 trucks and they both leaked).
I pulled mine out and washed and blow in it while the valve is closed. It is leaking.

If you see the inside of the heater/AC control box, you will see the door DOES NOT close the heater core 100%. So about 20% AC air will pass through the heater core when you have AC or simple outside air on. If hot water comes to the heater core this 20% opening will warm the cold air generated by the AC lowering your AC efficiency.

I practically saw this in my 92 car. I isolated the heater core due to the leak. During hot summer days I simply used speed of 2 or 3 max to cool my car. This is what lead me to this conclusion.

Try it your self, When you are running AC, check the water hose AFTER the valve and the return hose from the heater core, if the hoses are hot like the lower radiator hose, you are sending hot coolant in to kill the cooler air generated by the AC.


I hope this clarify.

which valve is this and where is it located?

 

[linwados]

I want the part number of Air Heater Core of T4R1997