Infamous thermostat housing coolant leak caused stink inside cabin. What do? | Ford Explorer - Ford Ranger Forums - Serious Explorations
  • Register Today It's free!

Infamous thermostat housing coolant leak caused stink inside cabin. What do?

Patrick Sheeks

New Member
December 10, 2019
Reaction score
City, State
Woodinville, WA
Year, Model & Trim Level
2010 Explorer XLT 4.0L
Hi guys. Just joined the forum as I just bought a used 2010 Explorer 4.0 l XLT with 51k miles on it. I wasn't aware of the common issue of the thermostat housing leaking coolant when I was inspecting the vehicle, so I missed it.

A few days after I bought the Explorer I noticed a big puddle of coolant on top of the engine and traced it down to the thermostat housing. I replaced it with the aluminum Simmons Auto Sportz thermostat housing and so far so good. No leaks.

I noticed the interior of the car stinking, but I couldn't put my finger on the odor. I got to thinking that this coolant leak has been going on for awhile and the smell on the inside could be from the coolant stench being sucked in through the heater intake near the back of the engine bay.

As a first step, I just got the engine bay steam cleaned today, and the shop graciously sprayed some HVAC deodorizer / disinfectant into the heater intake.

I am guessing someone has ran into this problem before since the t-housing leak is so common amongst the 06-'10 Explorers. Does anyone have any suggestions on how to remedy the odor inside the cab? I might even have to do a little more cleaning in the engine bay to totally remove the odor. Thanks!

Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!

Flush the valley of the engine with water. There are lots of places coolant will puddle 3" deep and will not come out without a good rinse.

Really? Doesn't it burn off? Plus I thought the steam cleaning would have done a decent job. Can I spray a weak garden hose in the valley on top of the engine?

I wouldn't I'd use a air hose and blow it off

I'd stick the water hose under the intake and just let it run. I've dumped a bucket of water there also to flush it out on the 3rd and 4th gens.

Steam cleaning only top cleans everything.

i just take a 5gal bucket of hot water and violently throw it under the intake then do about 100 on the e-way

^ that'll work too but I'd reccomend letting the engine idle for 10 min with hood closed before driving.

Flood the top of the motor with water, It may take several times because even a trace amount of coolant will still stink