So I was planning a flush on my 2012 Unlimited Rubicon and wanted to replace the thermostat while doing it.
Applied only a little pressure and the bottom bolt snapped. Top bolt is out, but the bottom bolt only has a little bit sticking out.
Hit it with PB all day yesterday and tried locking pliers, which can barely grab it and it won't move.

Thinking of drilling it out and either trying to save the threads or re-thread or use an insert if necessary.
Has anyone removed the cover that the thermostat bolts to and is it possible to get a new one? Is that called the Coolant Crossover Pipe / Cover?
If removed I can more easily access the area to drill straight on or if it's available as a separate part to buy new and forget drilling it.

Does anyone know the exact size bolt for the thermostat? So I can get new bolts and re-thread if I have to.



Bottom bolt snapped off

 

not sure if you've got enough there to weld a nut to but I'd try that before drilling and tapping/rethreading.

 

Just looking quickly it seems the cover is available. It looks like you could just remove it and get a lot better access to remove the bolt. Then just put it back on with a new gasket.

 

Just removed the crossover cover. It's 11 bolts for the cover.
Loosen the belt, need to remove the alternator w/ bracket and 2 pulleys. Came off no issue. The 11 bolts holding it on are low torque.
Also I previously thought the 2 thermostat bolts are blind, however they are not and that is probably why the bottom bolt failed with the elements corroding it.

I'll soak the broken bolt and work on that, then I'll try extracting.

Where did you see the Crossover Pipe / Cover for sale that fits? The Dorman model I found doesn't seem to have the same heater hose length. So if that model fits then I may need a piece of hose to extend.
Jeep told me it's not sold individually by them and you have to buy the whole assembly for almost $700.



Coolant Crossover Cover


Thermostat Bolts

 

Wow you are right for some reason when I put in your jeep specifics they don't have it. They have it for the 2012 Grand Cherokee 3.6. I wonder what is different. Can you get the bolt out now? Maybe some heat will help and you would just need the gasket.

 

The Dorman part looks identical except the heater hose connection. Can’t find a place that stocks it so I’d have to order to check if it fits.

I blasted it with PB and heat and won’t budge.
I may drill next.

 

You might find this helpful..

 

Good to know. Doesn't look like it's available for the Wrangler yet. I'll replace with the plastic one for now. The previous thermostat housing I took off was the original and still had not failed. I'm just replacing since everything was off anyway.

Also I was able to drill a small hole in the stuck tstat bolt / screw in the coolant crossover and hammer in a multi-spline extractor then wrench it out.
It took quite a bit of torque to get it to spin at first. Threads look good and I'll put it back together after I pick up a new gasket and tstat screws.

 

Well I started putting it back together and the passenger side idle pulley bolt stripped the threads.
Does anyone know the size bolt for the passenger side idle pulley (short bolt) for a 2012 so that I can get a heli-coil?

 

I guess this forum isn't what it used to be. However I think I found the bolt size. M8 x 1.25 and ordered a HeliCoil kit, bit, oil and install tools.
Will follow up after I can get it back together. What a nightmare!! And all in the name of preventative maintenance.