This water (no pun intended) is already fairly muddy and I don't want to make it worse.

But ............... Are any of the following statements useful and/or relevant :

1. The XK8 engine WITH the original expansion tank would have had two hoses, the routing of which is slightly counter-intuitive as they cross over each other.
2. Later cars only have one hose as the second (self-bleed) hose was considered by Jaguar to be unnecessary.
3. replacement expansion tanks have a blanked-off "stub" where the second pipe would have been connected.
4. If there's only one pipe, and there were originally two, where's the other one gone ??
5. If there IS a second pipe, but it is connected to a blanked off stub, could this be a possible cause of the problem.
6. Is it significant that the expansion tank has recently been replaced.

Just food for thought !!

 

My 97 has , I believe, the original tank. There are two hoses that issue from the inboard side of the tank, not the front. The forward hose goes to the radiator and the aft one to the thermostat housing.

 

Hi.


Take a look at this TSB:

 

RJ237. Yes - Exactly. Wiltoliv says his tank exploded and was replaced. I am just suggesting that although there may have been a major problem for that to have happened, it would be worth checking that everything has been properly connected.
The PDF above allows for three different scenarious :
1. All correct.
2. Correct reservoir, but hoses reversed (change of layout between 1997 & 1998)
3. Hoses reversed, and wrong hose connected to a "plugged up stud" because only one hose is required.

Easy to check and rule out before starting to replace radiators, pumps, engines, cars etc ;-) ;-)

 

The pdf supplied by oyster says it all.

 

I replaced the expansion tank with one exactly like the one that blew and I replaced one hose at a time as I changed it. There was only one bleed hose.

 

Fair enough. This is obviously a strange one. What is the history of the car ?? - have you been driving it for years, and then you suddenly had this problem, or did you buy it recently, and the cooling system imploded a few days after purchase.
Just check .............. is your vin after 018108.
Cheers,
David.