Hi,
I have to replace the expansion tank (CAC8612) on my 1991 Double Six. I have got it repaired but metal is quite thin due to rust and will leak again soon.
I have seen that an all aluminium alternative is offered by Limora, but it is relatively expensive (approx 420 €), and I don’t know if it is worthy, when I am going to replace the coolant in due time. SNG Barrat sells a non original one for 175; and Jaguar the original for approx 320 €.
Another question is if it is worthy to replace the water bypass pipe. It looks only a bit deteriorated, but being also steel made, I suspect it can be also internally rusted, although it is not so exposed as the expansion tank.
Any help to take a decision would be appreciated. Thanks in advance

 

I don't have any direct experience with any of them.

Personally I could never bring myself to spend $476 on an expansion tank.

I'd be sorely tempted to try the SNG Barrat tank unless someone comes along advising against it. If it's only half as good as the original part it'll last 15 years. Use the money you've saved to replace the bypass pipe.

Let's hear what others have to say.

I'll add that if you're opening up the cooling system on a recently purchased V12 Jag you might as well go for a full cooling system overhaul, including removal of the radiator for professional cleaning. Unless your car is an exceptional example I can almost promise an overhaul is overdue. Hoses, thermostats, fan clutch, radiator cleaning, flush-out...the whole thing. Do it all, do it right, do it once. Then you can forget about for a long time.

Cheers
DD

 

I recently ordered the complete set of Coolant/Heater pipes for my 1965 S type from SNG Barratt. Beautiful polished stainless steel, excellent reproductions.

SNG must have a set for a V12 or the needed sections.

As far as the expansion tank goes, any tank that fits and has the same capacity and ports will work, even a plastic one. If you can get to a salvage yard, you will find them in all shapes and sizes for little money.

 

The V12 HE engine tank is a specific design and fit, with specifically placed inlet and outlet recirculation spigots. A generic header tank will not work correctly.

 

at $476. USD for a new replacement , I would spend a day looking for an alternative at a salvage yard. Or I would fabricate one. Can't be THAT difficult.

 

Now we get into this weird area of "Originality" . Why in Gods name should we be held to some ridiculous standard of using thin walled corrosion prone garbage to maintain originality on an aging Jag if no one will bother to make higher quality replacements. I replaced the sieve on my S2 XJ6C with an off the shelf Aluminum Tank. Works great ! Hanging onto the old sieve, along with the Windshield Washer Tank just in case

 

Nobody is "holding" anyone to any particular standard. Lots of choices; we each get choose our own poison

Some of the things I consider are price, quality, ease of installation, and end appearance. I'm not a slave to originality but I don't like stuff that looks too far out of place. Your coolant tank, for example, doesn't suit my tastes in that regard. That's not a criticism; it's just a difference in taste.

The original tanks lasted for a long time, often decades, so I'm a little reluctant to speak too harshly about them....even though they may not have been the best choice Jaguar could have made. Whether or not an aftermarket replacement for 175 Euro would last that long, who knows? Other AM replacements might be a better design....but can start getting awfully expensive!

Cheers
DD

 

My expansion tank was full of pin holes and very thin. I coated the inside of the tank with Caswell gas tank sealer. Works fine. It's been on the road for 7 years. Small kit is less that $50.

 

I have repaired a couple of header tanks with fibre glass and epoxy resin.
I did my first tank on a 1974 S2XJ12L in about 1985.
My second was in a 1981 S3XJ6 around 1999.
If it has pinholes, apply the first layer with nexous tissue which will seal the holes but not let any epoxy into the tank. Let that go off.
Then use layers of chopped strand mat or roven wovings on top of the nexous tissue. (The choice is up to you)
This is very cheap and simple to do and will last a long time.
Bill Mac
MK1
MK2
S3XJ6
X300
​​​​​​​15 previous Jags MK5 to X308

 

Would you like it better if I painted it black ?

 

yes, and no. either would be fine in my car.

 

Excalibur - (don't know your first name) - I like your tank and am getting ready to replace mine. Where did you get yours?

Many thanks, Bill

 

eBay !

1L Aluminum Radiator Coolant Overflow Bottle Expansion Reservoir Tank Silver | eBay

Several to choose from !
Al

 

I am restoring a 74 XJ12 currently and ran into this problem (my original one is the rusty one). Of course you can buy new, but I found a decent used one (the black one) from an XJS for $35 on EBay.

I considered taking it to a shop to have the filler necks swapped but then had the idea to cut the filler neck and replace with radiator hose. Not original, but cheap and works.

just an idea to share with future searchers

 

Bullittandy - Great Idea! Do you remember what size (inside diameter) hose you used?

Bill

 

The filler neck has a diameter of ~ 1 3/16" and so I used a hose with an inner diameter of 1 1/8". Good luck!

 

Fine, I'll paint it black !

 

For a car that is unlikely to be a daily driver, the SNG Barratt after-market tank is the best option in my opinion. Fits straight in, and looks like the original, and probably as good as the ones Jaguar fitted. If it lasts 15 years that isn't a whole lot of money to spend. Better save money for the other inevitable jobs that will come around.