Hello everyone, I’m new here and need some help diagnosing a problem with my 2000 Dakota with a 3.9. It’s experiencing a large coolant leak from a small(1/2) hole in the passenger side of the firewall. the leak wasn’t super bad at first but I just filled the coolant up from empty this morning, drove 10 minutes to work, came home after work and it had all drained out. If anyone has any ideas what it might be that would be super helpful!

 

Does your defroster fog your windows? About the only think I can think of, would be a blown heater core, and the coolant running out the condensate drain for the evaporator core.....

 

This exactly. If you look above the passenger side exhaust, you'll see the 2 heater hoses going into the firewall. About 4-5" down from those, you'll see the evaporator condensate drain behind an aluminum heatshield. . If coolant is coming out of that, it means your heater core has a hole in it and is filling the HVAC box under the dash with coolant.

In the photo below, it's behind the heat shield to the top left of the fan. You can see the drain poking out the very top of the shield. The heater hoses are obscured directly above.

https://photos.app.goo.gl/byJgipAg5njWnhWo7

 

Your heater core is leaking. Probably too much for aluma-seal to stop. I put a new core in my '97 and it was a booger. I went ahead and replaced the a/c evaporator core while I was in there as the dash assembly has to come out. Supposedly, you can drop the steering column and tilt the dash back, but it was just easier to pull the steering column and dash assembly. The previous owner was a HEAVY smoker and this let me clean all the tobacco residue out while I had it apart. This is what the old and new cores looked like while I had it apart.



All those green stains are where the coolant was leaking. In the short term, you can unhook the heater hoses and splice them together. However, you won't have any heat when you do that. Somebody didn't keep the coolant fresh over the last 25 years. You need to change it every 4-5 years. If you go to a shop, because the dash has to come out, it won't be cheap.

 

[QUOTE=ol' grouch;3596281]Your heater core is leaking. Probably too much for aluma-seal to stop. I put a new core in my '97 and it was a booger. I went ahead and replaced the a/c evaporator core while I was in there as the dash assembly has to come out. Supposedly, you can drop the steering column and tilt the dash back, but it was just easier to pull the steering column and dash assembly. The previous owner was a HEAVY smoker and this let me clean all the tobacco residue out while I had it apart. This is what the old and new cores looked like while I had it apart.



Agreed, I did that But I really don't need Heat here in SE Texas... The Blower motor was next to go
it got to where it would run, if I hit the housing. then nada. had a friend of a friend replace the motor, and squirrel cage. that lasted 2 months because he didn't tighten the cage to the shaft and it spun off hitting the housing. and jamming there.

Now, I don't use the A/C either. I do what they did before A/C. I open the windows...
Really old man must equal, HE-MAN! LOL!
Actually, when it gets to be over 90 degrees, I stay home in the A/C.
So Really old man, must equal, SMART-Guy! LOL! Hahaha!
Probably not... just SMART A$$ hee hee!