Leaking thermostat housing (What am I doing wrong?)

MountaineerTom I didn't consider that but at this point I'm willing to pay the $30 for a genuine MOPAR thermostat. Buy once, cry once.

Gollywomper I agree, I need to clean that recess better.

CODE5 your housing looks to be in much better condition than mine. I think I'll go to the stealership and get a new housing and real Felpro gaskets instead of the ones I tried before from O'Reilly's.

May be a couple days before I get to all this. Fifth time's a charm, right?

Question: should I expect any challenges transferring that sensor to the new housing?
 
MountaineerTom I didn't consider that but at this point I'm willing to pay the $30 for a genuine MOPAR thermostat. Buy once, cry once.

Gollywomper I agree, I need to clean that recess better.

CODE5 your housing looks to be in much better condition than mine. I think I'll go to the stealership and get a new housing and real Felpro gaskets instead of the ones I tried before from O'Reilly's.

May be a couple days before I get to all this. Fifth time's a charm, right?

Hang in there with it! I had been chasing a coolant leak since buying this Jeep in April. Finally discovered a leaking thermostat gasket and decided to get the OEM temp thermostat while I was doing the job. I bought all of it off Amazon. How tight did you torque down those hosing bolts?
 
Hang in there with it! I had been chasing a coolant leak since buying this Jeep in April. Finally discovered a leaking thermostat gasket and decided to get the OEM temp thermostat while I was doing the job. I bought all of it off Amazon. How tight did you torque down those hosing bolts?

First time I cranked them hard. Subsequent times less and less. I don't trust my torque wrench at only 20 lbs.
 
MountaineerTom I didn't consider that but at this point I'm willing to pay the $30 for a genuine MOPAR thermostat. Buy once, cry once.

Gollywomper I agree, I need to clean that recess better.

CODE5 your housing looks to be in much better condition than mine. I think I'll go to the stealership and get a new housing and real Felpro gaskets instead of the ones I tried before from O'Reilly's.

May be a couple days before I get to all this. Fifth time's a charm, right?

Question: should I expect any challenges transferring that sensor to the new housing?

I used some of this on the threads when I installed the sensor. Same for the metal tube on the water pump.

IMG_8982.JPG
 
I bought a cheap thermostat housing from O'Reilly's for $20. It worked fine (once I cleaned up the casting imperfections.) I probably got lucky. I didn't want to wait a week for shipping.

I believe there are billet aluminum versions of the housing too...if you really want to drop several hundred bucks.

-Mac
 
All of the crap in The recess has to come out. It could be causing the thermostat to stick out, this not allowing the housing to fully seat against the head.

View attachment 360995

Thats where your problem is. Gotta clean that junk out for it to seal and don't need rtv or a expensive gasket, Just clean and not warped from over torque on the bolts.
 
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New parts didn't come it yet but I started.

I was very careful. First I gently removed the gunk with a cutting chisel. Then sprayed with penetrating oil (I don't have any WD-40), and wire brushed with a cheap dremel on its lowest setting. Vacuumed, blew with compressed air, and wiped down.

Here's what I'm working with:
20220923_185158.jpg
 
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Normally if the manufacturer does not call for sealant I try to avoid it but with the pitting and scratches in the machined surface in this case I would use RTV to try and fill the voids. The new housing as long as it is machine flat and there are no defects you are probably good without RTV on that side of the gasket. Put the new housing against a flat true surface to check that it is correctly machined. Glass will work or a metal straight edge.
 
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New parts didn't come it yet but I started.

I was very careful. First I gently removed the gunk with a cutting chisel. Then sprayed with penetrating oil (I don't have any WD-40), and wire brushed with a cheap dremel on its lowest setting. Vacuumed, blew with compressed air, and wiped down.

Here's what I'm working with:
View attachment 361556

I may have missed it but did you jb weld the spot on the right?
 
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I think there's a corresponding open spot in the housing for the sensor and the bypass to the heater core, so that spot is directly exposed to coolant instead of having the housing and gasket stuck to it. Probably why it's smoother and has deeper pitting around the edges.
 
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Did you use that buffing wheel to polish the mating surface?

Yes, after scraping it with a razor blade. Be sure to stuff a rag in the head to keep any debris out of there. I think I used the medium grit. I got the kit and some extra discs at Lowes.

914CC2B1-1556-4F29-B497-2B70D69506DC.jpeg