Today I took a spirited drive at night. Everything seemed fine. When I finally made it home, I immediately felt the familiar scent of sweet coolant. I opened the hoo and was greeted by an expansion tank that was leaking severely through the seams. According to my records, the last time I replaced that tank was On December 13, 2017. This expansion tank is barely a little more than 3 years old and it's already failed.

How often do you guys find yourself replacing these coolant reservoirs? Because of the expenses I incurred with the HID and LED projectors, I am a little hesitant to once again pay full price for the OE expansion tank. Has anyone bought the $40 URO tank for sale on RockAuto? It looks identical to the OEM tank. (P/N MJD4400BA)

Welsh has it for $55.95 (it's quite possibly the same as the URO from RockAuto). SNG Barrat has the OEM for special order at $156.00 and the "aftermarket reproduction part" which might just be the URO at $85.98.



The coolant was dripping out, the hoses are dry.

 

The one in my 97 was probably original and had ten yrs. and almost 100K mi when I sold it. I wonder if the OEM tanks on more recent cars are identical, as in made by the same supplier using the same materials and process. My impression is that OEM may mean supplied by Jaguar, but not necessarily by the original fabricator.

The octopus hose I replaced last year was OEM, but I couldn't get it to seal to the expansion tank. no matter what type of clamp I used. I finally cut it off below the elbow and replaced that section with a piece from a heater hose.

 

Hmm, I think it's interesting that the one on your 97 lasted that long. How long did you have that car? Did you ever replace the expansion tank? Are you sure a previous owner never replaced it? I did a search on the forums and another member suggested between 4 to 5 years. Perhaps, the tank in the 97 XK8 is more durable than the one in the '04 XKR? They are not the same part at all.

 

The tank looked old and there was no record of it being changed. I sold the car about four years ago and only owned it for three or four years.

 

2006 XK8. I replaced what was probably the factory coolant expansion tank in September 2017 with the $50 (at that time) version from rockauto.com. I inspect it as part of my fluids & tire pressures check every weekend. Thus far it appears to be holding up but we all know that these plastic tanks are susceptible to leaks at the hose nozzles as well as at the seams. Regardless of where you source your next one, be sure to continue to inspect it on a regular basis....

 

I did end up ordering the $40 tank from RockAuto. I figure, it will probably last just as long as the Jaguar supplied replacements, so why spend extra on it? I do plan on keeping the old tank and taking it to a machine shop to see if it is possible to have a custom aluminum tank fabricated. I do wonder how the coolant temperature sensor, and the coolant level float would be transferred to the aluminum tank. I hope the machine shop can get it done. I would gladly pay the premium for a tank that will never fail again.

 

My tank is original to the car, an ‘02 XKR with 164,000 miles on it. I think there are too many variables over the years to place a likely expiration date on the tank.

I did have a coolant seepage from the hoses last year. I replaced the hose & clamp, although all it really needed was a new hose clamp.

Z

 

The one on my '98 is original. I'm the original owner so I know it's never been replaced.

 

You have also barely driven it with at most about 2,000 miles per year. Yours has not really experienced many heat cycles. However, z-ray, with an original tank at 164,000 miles truly boggles the mind. Did the quality of these tanks dip?

 

to reduce the heat soak endured by the multitude of pricey hoses, I routinely open the hood / bonnet when the car is in my garage. This practice might have some positive impact on the tank. I know this is being pretty **** / obsessive but I really don’t want to replace all the hoses before I have to.

but I’m sure the owners in the car’s previous to me (115,000 miles / 17 years) were unlikely to care about such maintenance strategies, and also were more well adjusted and didn’t obsess over the car like I do.


Z

 

My '98 has 26K miles on it and it is original.

 

How can you drive your car so infrequently?

 

An update on this: the URO tank seems to have a bad coolant level sensor. It intermittently indicates low coolant. Upon inspection, the coolant is full.

I still have the old tank. Is there a way of switching the coolant level sensors or will I have to return the tank and buy an OEM one?


I think my float is just stuck. The temperature is reading in the normal range (I have RealGauge).

 

I had a similar problem with an aftermarket tank giving erroneous readings. I fixed it by using the sending unit from the original tank. Popped right in and no more bad data.

 

To add on, to my knowledge the coolant expansion tank in my 97 is original. As you've noted, completely different part. Now that I've said something, it'll probably fail.

 

I think that is what I will do.