The PO had the cooling system overhauled before I picked it up, so I have to check but pretty sure I have a new t-stat. My XJ warms up in NO time, and blows heat quick too.

Edit: can't find what p/n on the old paperwork though. Useless post!

So for what it's worth (no , I did not read the whole thread) . I bought something that said " Moto Rad". I could see light through when it should have been closed. I'm pretty sure I bought it at Napa. (who I generally trust). I bent it so it seems to close, and saved if as a spare.

I installed Mopar # 1-83501426AD (don't get bent if it's not "AD") just make sure it's 195* and you install it with the hole up at 12:00.

I can't find the photo of the light coming past the Moto-Rad T-stat.

This is the MotoRad I saw a crescent of light coming through. In my quest for max milage, I canned it for the OEM. I haven't pulled the Mopar T-stat to see if it also is no longer seating perfectly.

Anyway, same as the others, but I did see it not seating, then bent it so it does.

Just put a fail safe in Saturday as my 98 took forever and a day to get to temp and had lack luster heat below 30* ambient temp. Now the temp comes up quickly to 205 and holds steady, but heat still sucks. Ran it for almost an hour to bleed, no air, both core hoses are hot. sigh...

On that first page--some of the most beautiful photos of a thermostat I've seen..lol.

How long does it take for your jeeps to warm up with these stats? I have a 195 I got from Napa and haven't had any problems with it, although the jeep can take 10 minutes to get warm (idle) and I feel the heat could be warmer. But no running or temp issues with it.

The "Mopar" Motorad looks beefier than that Motorad.

Hey now!.... If your refering to my pics, was just trying to help out.....lol.

A month ago I did a flush and previous owner had a 160 in it, replaced it with a AutoZone motorad, which was a fail safe. Well, that fail safe, fail to safe mode....lol. Figured I'd go to dealership to buy one, didn't realize it was made by motorad now till I saw this thread and look at the tstat. Still haven't thrown it in yet tho......lol.

2 minutes driving and there's heat coming out the vents. 5 miles down the road at operating temp.

"Failing to safe" (overheating) this time of year......hummm, further investigation needed.

We need a source for the HighFlow Motorad.

No over heating, pretty sure its stuck open. "Failed and in safe mode".....is what I meant....lol.
I let it sit and idle, it almost makes it to 210. Driving down the highway its drops to about 155
, halfway between 100 and 210, and no more heat.

I'd be willing to bet that a so called "fail safe" stat will have to see some pretty toasty coolant temps in order to lock in the open position (fail safe). Toasty coolant temps in cool/cold winter ambient temps would seem to signal a cooling system problem, no?

Does it ever allow you to get heat in another cycle? Or, is it stuck open?

Possibly - in another thread someone had mentioned the previous owner installed a failsafe 160 degree thermostat. That would "fail open" as soon as the engine reached operating temp.

Hummm.....I would think the "fail temp" of a 160 "open temp" stat would be the about the same "fail temp" as a 195 stat, say 240* just as an example. If it's not, that seems kinda useless.