Thermostat housing hot
 

I got home and Parked my car as usual when a neighbor knocked on the door and told me my car was on fire. Of course they were just over reacting. It had the upper thermostat hose that goes to the reservoir bust. I notice a decent amount of heat comin from the motor as well but didn't notice a change on the gauge. I thought it could be the thermostat. I changed that and no luck. I took the drive belt off and spun the Pump and didn't hear any bad noises. I'm confused at what this could be. I need to get it fixed ASAP for work and school. Thanks in advance Joel It seems like when it gets hot he only place getting really hot fast is the thermostat housing

The housing should get hot fast, but you give so little details, I cannot tell you what it might be.

Neighbor said the car was on fire, does that mean smoke or steam was coming out?

Do not throw parts at a problem, diagnose the issue. Let the car idle with the hood up and then look to see where the problem is, also is there coolant under the car?

Yes there was as the hose had came lose. The smoke was comin from the radiator and where the coolant had sprayed. Then I guess I should let it run longer and see what happens. Any other things i can try? I'm just nervous. I don't want to ruin anything

Update: the hose on the top of the thermostat housing got hot. The one below didn't get hot and the small hose on th top that busted got hot. Does this mean the radiator is bad? It was also smoking some from the radiator.

First get a pressure tester and see where the leaks are. Fix them. Fill and bleed the coolant system. Then see where you are at. If you are losing coolant, sometimes it drops onto a very hot surface like the exhaust and you do not find a puddle under the car. But you will eventually overheat.

Which small hose?????

The 3 inch long hose or the 5/8" hose going to the intake/block...

How long had the car been running before you checked the upper and lower hoses, come on, give us everything you know!!!

+1

I couldn't exactly decide which hose either.

https://www.jaguarforums.com/forum/a...-hot-hoses-jpg

The Yellow arrowed, Purple arrowed or Green arrowed?

Graham

Both of them are hot. The small 3/8 hose busted. It doesn't leak. It's more of the pressure building up and causing the hoses to bust. The three inch hose gets extremely hot as well.

Looking at the pic in post #7, the yellow arrowed (Bleed Hose) and green arrowed (Bypass Hose) should get too hot to touch as should the black plastic Thermostat Housing.

You've replaced the Thermostat so there should be no possibility that is sticking. Without removing the Water Pump you can never be absolutely certain about the plastic impeller blades but actual breakages seem to be relatively few except on the early cars.

If the system is building up excess pressure, the next possible cause to investigate would be a faulty Expansion Tank Pressure Cap. There have been several report on the forum of these failing. The Cap has to open to allow excess coolant from the Expansion Tank to flow into the Atmospheric Recovery Bottle behind the front wheel arch liner.

Graham

Is this hose still busted? The system will continue to overheat for sure because it is open to the atmosphere unless this is fixed first.

Thanks for the replies! I bled the air out of the system and everything has been great! Thanks for all your help! I do have a small minor leak from the reservoir. I can see where it's been dripping underneath the tank. Hasnt been dripping on the exhaust so I haven't smelled it. Some older guy raced me In his tundra. I know the xk8 is no race car but it sure did put him in his place.