I cut the housing apart & pulled out the T-stat. (
Then my keyboard stopped responding to the letter "O" so I couldn't write "thermostat open" - even zero wouldn't work. Since my password has an "O" in it, I couldn't reboot to check for software problems either so I had to go buy another )
Here is the housing cut apart along the crimp line. It would have cost no more money to simply thread the outlet port or put 2 tabs with screws on them to clamp it shut. Makes no sense whatsoever.
Here is the opened thermostat after a couple of minutes boiling water. This looks like a decent opening - in fact based upon spring compression I don't think it could open any more.
However, here is what it looked like when I originally peeked down the hole on my first few attempts at testing. Perhaps I didn't let it boil long enough to heat up the housing?
Quote:
Thermostat, liberty - 2.8l diesel - 2.8L DIESEL 05-06 $114.00 $83.20
Now I know why you call them a Stealer.
$114 is the raised voice, argued-down price. The stealer list price is $149 and a week to special order. I also ordered a new sending unit so that when I put it all back together and it overheats again - and I rather suspect it will - I'll know what the problem it is NOT.
So far:
Antifreeze: $80
Sending unit: $50
Thermostat: $114
Ticket for expired tabs on a tuck only drove because the Jeep was dead: $130
Driving said truck (super cab dually) through hard core rush hour traffic for a week parking in small downtown Seattle parking stalls and paying 2X my normal fuel costs: $100.
Bloody knuckles and a newly formed need for blood pressure medication and a shrink: Priceless.
When I'm finished it will have:
New thermostat
New sending unit
Thorough back flush
New antifreeze
Other possibilities:
* Head gasket: But there are no bubbles, no loss of fluid, no steam in exhaust, plenty of power, last recorded hwy mileage 28.
* Blockage in cooling fins: Examined carefully and found no debris at all. Back-rinsed thoroughly just in case.
* Blockage in radiator core: Tests show good flow through radiator. Back flushed just in case.
Electric fan: It turns on when hot as expected so I doubt there is a problem. I still need to check more thoroughly wen it comes on and how long.
* Water pump: In my experience, a water pump's primary failure mode is leakage from a bad seal followed by bad bearings (often caused by leakage). On a rare occasion one my plug. Extremely rarely the impeller might break. In this case I thoroughly back flushed it but saw no indication of blockage or debris.
* Gauge cluster: I was told this TSB does not apply to my VIN#. I had a spirited conversation with the service manager and said I wanted them to do the TSB anyway.
* Viscous clutch fan: Maybe, but it moves a heck of a lot of air when the engine is hot. I also checked it using some suggestion from another thread including watching it's behavior when trying to free spin it.
* Lack of lubrication: If it is getting hot from lack of oil, other more serious symptoms would be present.
* Voids or bubbles in system: Doubtful it would be an issue on a car with 35K on it running factory fluid.
* Viscous cabin heater: A rare problem
My gut feeling: The cooling system is under-sized for long, slow uphills on hot day,
If it still overheats after all of this, I'll load every heavy object I know onto my trailer and start driving it up and down the steepest section of logging road I can find - mid afternoon with the AC on - until I MAKE the problem into something that IS covered by the 7/70 warranty.