99 xj8 vdp
 

Just purchased this car a few days ago and as long as it sits at idle it holds normal operating temperature. If I drive it the temperature will start rising and run hot. I'm suspecting a faulty thermostat, but wanted other opinions. ALso is there an overflow valve or tube on the coolant tank that when its running hot will open and leak water out so the tank doesn't explode? I have a drip under the car when it runs hot....after it returns to normal temperature the drip stops and if car is running in the garage it doesn't run hot or drip any water. Any ideas?

Thermostat- most likely and cheapest place to start.
Overflow- allows for coolant to escape (which I imagine it needed when it got hot)

That's what I'm gonna assume an start there tomorrow. Thanks.

FYI- I just went through this last week with my XK8 rebuild. Fine at idle, then when I drove it a bit started to get hot, fans on high. Changed out the thermostat and she's been running perfect since.

Definitely follow up on D's advice. In addition, I strongly recommend installing the Real Gauge. Basically the temperature gauge in the X308s works more or less like an idiot light, i.e. it will either say you are running ok or wham, boom, crack - you have overheated. By the time it goes to hot it could be too late.

Contact Stever at <steve.klonsky@comcast.net>. He makes and sells Real Gauge that turns the temperature indicator into a "live" gauge. Good luck.

Thanks guys

If I was keeping mine, I would totally get the realgauge.