Hi wondering if changing the expansion tank on my 2004 V6 2.5 petrol automatic is within my limited capabilities. Losing coolant with no apparent leaks. Previous threads suggest this as a possible culprit. Should I consider changing hoses at the same time? Any help gratefully received
Regards Dave

 

Just keep topping it up and give the leaks a little time, then you'll see them. Have your cap tested and make sure it releases pressure at or before 20 lbs, otherwise the pressure keeps building. Look at everything when the car is running and up to temperature for leaks. I had a tank have hairline fractures that spayed coolant when the car was running, but not when it was sitting. If so, you could patch it with aluminum tape to keep the cracks from spreading until you get another tank. I recently got a new tank made by Rein which was good quality. If the hoses look and feel good and are not leaking, I'd just leave them.

 

Hi thanks for your input, I will do as you suggest and give it plenty of visuals whilst running. The cap gives when it’s turned so far, is this correct? Any idea what the expected pressure of the system should be?
Regards Dave

 

Following a cold soak, preferably overnight, use a cooling system tester to pressurise the system to 1 Bar and check for leaks. If the gauge on the tester begins to drop, use a torch to search for leaks around hose joints and around the water pump.

 

having the car up on stands or ramps helps a lot too.....if it has belly pans and covers take them off too and look from underneath....you can even use a uv dye made for coolant and a black light if necessary

 

hey!

other colling system issues can be: melting radiator and its cracking side plastic tanks due to old age (make sure to check it. ive lost all my coolant and overheated my engine cause of a radator that gave up on me at 6500rpm)
leaky: pump, plastic tube where the sensor is, elbows on the engine, dccv.
one hose that usually gives up is the engine central lower tube to water pump rubber connection.

good luck!

 

Hi been some time since last post but eventually went ahead and swapped out the coolant expansion tank. Ordered from supplier on EBay. Straight forward job but the supplied sensor with the new tank is physically different to the original. It looks a bit like a reed switch, and does not detect the level, thus the low coolant light does not clear. Any idea how this type of sensor operates
Regards weltidave

 

Assuming that the aftermarket tank was cast from a Mould replicating the original, a replacement sensor (yes, it is a reed switch, IIRC) is available to replace the bad unit; the catch is that it is not available as a Jaguar part but IS available as a Land Rover part for a car of similar vintage.

 

More details in this thread:

https://www.jaguarforums.com/forum/s...sensor-216006/


Link to sensor:

https://www.rockauto.com/en/catalog/...el+sensor,2184


It's for a 2004 Range Rover.

OEM #PCJ500020

Standard Motor Products #FLS169

Also, make sure the floating magnet inside the reservoir is free to move up and down to actuate the reed switch.