Hi all. Only had my 95 XJS convertible, since September 07. Picked it up in LA, and drove it back to Arkansas. Temperature has never been a problem, just the opposite, ran rather cool. Would barely get above the cold mark on the gauge. I know its important to have the engine running at its proper operating temperature, but, believe it or not, this is the first time I've really had enough free time to replace the stats. I knew it had to be either, no thermostates, or stuck open thermostates. Being from LA, I was kinda leaning towards no thermostates, figuring maybe previous heating problems, (considering my luck on such matters)! Its been fairly warm until recently, so the cool running engine was more of a blessing, I think. Now that its getting cold, the long warm ups were getting to be a pain. It would warm up, and let the heater get warm, but took forever. Got the proper Jaguar Waxstant thermostats, with the jiggle pins, and installed them today. I was surprised to find thermostates already in place, but as I suspected, they were stuck open. After installing the new ones, the temperature rose to the middle of the N, right where its supposed to. Didn't move above it, just stayed there, either idling, or running. Used to have a flow of cold air coming in right at my feet while driving, but now is warm, and the rest of the vents are hot. Think I'm getting a little air leakage from another vent under the dash, but livable as is. Anyway, if you've never changed thermostates in a V-12, its really not very hard, just have to move the air filter boxes, and a couple hoses on the drivers side. Passenger side is very easy, once the air box is removed. This is the first work I've done on my engine, (if you want to call it that) and once you get past the intimination factor, was a piece of cake. The factory service manuels are very accurate. Anyway, great to have things back in order. Keith

 

Keep an eye on the thermostat. The v12 engines do not like to get hot. They will drop a valve seat in the blink of an eye. Sounds like you spot on for now!