Coolant smell through heater and small puddle

[rustwhatrust]

After a couple days of severe cold (-20s) I had a small puddle of coolant under the front end of my explorer. Started it and let it warm up but couldn't spot a leak, pulled it over fresh snow and let it idle several minutes and no coolant dripping. Oil looks ok and doesn't smell, but took a short drive today and can smell coolant through the heater vents. Can't spot anything under the hood that looks wet and it's not leaking a drop now. Can see coolant in the radiator and the plastic reservoir so I don't think it's lost much antifreeze. Any guesses where to start looking?

 

[~X~]

Your heater core is probably leaking. It's an easy job to replace it. If coolant is dripping in the cab then that's the culprit.

How to: 1st Gen Explorer Heater Core Replacement Diary

[Preamble: Ok.. I know it is no big deal, not much harder than changing a spark plug, but ya know, we all started someplace in our auto repair, and this one is a good "starter" job for a newbie mechanic. So.... that said, here we go: Ah, summer, the time when a young man's heart turns...

www.explorerforum.com

 

[Pete Deering]

After a couple days of severe cold (-20s) I had a small puddle of coolant under the front end of my explorer. Started it and let it warm up but couldn't spot a leak, pulled it over fresh snow and let it idle several minutes and no coolant dripping. Oil looks ok and doesn't smell, but took a short drive today and can smell coolant through the heater vents. Can't spot anything under the hood that looks wet and it's not leaking a drop now. Can see coolant in the radiator and the plastic reservoir so I don't think it's lost much antifreeze. Any guesses where to start looking?

My water pump started leaking from the weep hole of the water pump.I would take a short drive , park it and when looking under the car, there was coolant on the ground.
I believe it was because of the extreme cold on the shaft.
I also experience heater core leak. If you used the front defroster the coolant end up as a film on your windshield.

 

[rustwhatrust]

Your heater core is probably leaking. It's an easy job to replace it. If coolant is dripping in the cab then that's the culprit.

How to: 1st Gen Explorer Heater Core Replacement Diary

[Preamble: Ok.. I know it is no big deal, not much harder than changing a spark plug, but ya know, we all started someplace in our auto repair, and this one is a good "starter" job for a newbie mechanic. So.... that said, here we go: Ah, summer, the time when a young man's heart turns...

www.explorerforum.com

Thanks. I didn't even think to look inside the cab. I'll read through that post and dig around a bit tomorrow.

 

[ChildIdenticant]

I had a small puddle of coolant under the front end of my explorer

Welcome to ExplorerForum!

 

[BKennedy]

There is a drain for the heater core through the firewall. It's on the right or passenger side on the lower side of the firewall below the blower motor. If the core is leaking, it will be leaking out of there.

Edit: I recently replaced the heater core in my 1994 Explorer. It took about 30 minutes start to finish. It's a very simple job due to the large access panel inside. I cleaned the heater box out very well, but still get a slight smell of coolant the first few minutes of using the AC or heater.

 

[1sicbronconut]

See lots of plastic tank radiators leak in the extreme cold, the plastic tank and aluminum core expand at different rates and the seal in between the two will start to leak.

 

[Pete Deering]

See lots of plastic tank radiators leak in the extreme cold, the plastic tank and aluminum core expand at different rates and the seal in between the two will start to leak.

A lot of people remove the radiator too do other service work. And leave sitting empty. The rubber gasket dry up and when you reinstall the radiator, they are prone too leaking.

 

[rustwhatrust]

There was no sign of leakage in the heater core, or anywhere else now. Weird. Have been driving it normally for several days and no sign of the coolant level dropping. The coolant in the reservoir looks fine, and no more antifreeze smell in the cab. I'm chalking it up to the great mysteries of life when it's 20 below.

Thanks to everyone for the ideas and suggestions, and for the welcome. I've had this exploder over 20 years and have looked to this forum for answers many times, and now that I'm registered maybe I can chip in and help someone else out.

 

[markar]

After a couple days of severe cold (-20s) I had a small puddle of coolant under the front end of my explorer. Started it and let it warm up but couldn't spot a leak, pulled it over fresh snow and let it idle several minutes and no coolant dripping. Oil looks ok and doesn't smell, but took a short drive today and can smell coolant through the heater vents. Can't spot anything under the hood that looks wet and it's not leaking a drop now. Can see coolant in the radiator and the plastic reservoir so I don't think it's lost much antifreeze. Any guesses where to start looking?

I had a similar experience with my 1993 Eddie B. XLT 4.0,,head gasket was blown. i DID have luck with a $$ off the shelf product from autozon and got another 40,000 miles until the engine blew at 300 miles shy of 300,000. Also 2001 4.0 XLT had heater core leak and since I nobody rides along i didnt notice the wet carpeting on passenger side,,replaced heater core. Good Luck. it is NOT normal to smell it,,check the carpet.