coolant smell in the cab

[spotted dogs]

Hi there...winter has hit hard and I have noticed a few times that when the heater is on (climate control/automatic) I am getting a pretty good wiff of coolant inside my cab. I have no leaks that I can see....coolant level appears ok. Is this the first signs my heater core is going kaput?

 

[alexefron]

The heater core can have small leaks that are hard to detect. maybe someone has an idea on how to test this?

 

[Sarge_AF]

Does the windshield have a tendency to fog up? It sounds like the core going bad to me.

 

[spotted dogs]

no fog...

That is what I would expect but they are not fogging on me...

 

[410Fortune]

coolant smell in the cab = leaking heater core 99%

Check the pass side floor and behind the glovebox. Look under the carpet and up along the firewall. See coolant?

Not too bad of a job, not too expensive either.
I think I am on my 4th core in the BII? 280K miles.

IMO I would not buy one from Checker or Autozone

 

[spotted dogs]

Will do so...I actually just took out my summer mats and put the winters in and didn't notice anything but I will do a closer check....thanks for the tip.

 

[XplorerKid]

i had a coolant smell on mine, and ended up being the heater control valve thing under the hood, 15$ later, and no more smell or leak...

 

[spotted dogs]

heater control valve...

where is this located?

 

[410Fortune]

the heater bypas valve is under the hood, passenger side, above the heater box. Where the tqo rubber hoses feed coolant to the heater core through the firewall, you will see a plstic valve with a vacuum line going to it.
It is common for these to leak and they are easy to replace.

 

[spotted dogs]

I can see where the two pipes go in but can't locate the valve?...unless I am blind!

 

[410Fortune]

Here is my 88, but yours is similar.

See where I have red hoses going into the firewall for the heater core? Black hoses come from the engine? the valve is right there, just under my blue hood support.

Sorry best picture I have of it.

 

[spotted dogs]

thanks for the pic...On mine I saw 2 hoses going in on the drivers side of the rectangular box (not sure what it's called) to the right of your hoses (my" box" is wrapped in heat foil) but I will look again. Is your valve the item on the engine side of the firewall and red hoses with a bit of white on it?
cheers!

 

[410Fortune]

yes it still ahs the white sticker on it.
Your heater box is on the drivers side?

On the older trucks (like mine) only the engine side of the heater box is covered in heat foil. Also my truck will always be a bit different since I built everything under te hood myself hahaha The 88 did not come with this valve, I added it so I can stop the hot water from flowing through the heater core in the summer months (keeps the passengers feet cooler)

 

[spotted dogs]

my mistake....to clarify the box is on the passenger side like yours but the hoses that I can see easily enter on the drivers side of the box (opposite of yours)....but the pic really helps so I know what to look for now.
thanks!

 

[Flydog]

I have a 2002 Ford Explorer and I am losing coolant on the passenger side of the vehicle. From the top I cannot see any leaks but from the bottom back near the firewall (passenger side) I can see coolant leakage running down the hoses and back onto the frame and underside of the vehicle. There are some things in the way that I have not removed yet to see where the leak is coming from. I do not see any evidence of leakage inside the vehicle.

Does anyone have any ideas on what may be leaking and how to fix it ? From some of the other messages it sounds like it might be the control valve that is near the heater core in front of the firewall but the messages were from owners with a different year Explorer than mine.

I would appreciate any help and advice anyone can give me.

Flydog

 

[410Fortune]

Sounds like the classic water bypass switch leak discussed in this thread. Many year explorer's use the same valve in the same position (basically) as pictured above

Check those hoses/connections for the leaking.

 

[Flydog]

Thanks, I'll check the hoses and then the valve for my leaks.

Flydog

 

[expblue]

i'm getting the same problem it smells sometimes going to the dealer
my windsheild fogs up when i leave the def on and restart the truck
not all the time and it takes a while to warm up

 

[410Fortune]

IF ITS FOGGING UP YOUR WINDOWS and you have a strong smell of coolant then it is 99% likely your heater core is leaking.
Look for coolant on the firewall behind your glove box.