New X350R/Super V8 header tank. MY04 early model.

[J44EAG]

A new header tank to be fitted at 92K miles due to a small but annoying stub pipe leak leading to coolant loss. Issue started at 78K miles.

So here is a new C2C41300 tank before fitting. This part number appears suitable for the supercharged XJR manufactured between 2004-2009.

This part is only available via the Jaguar parts supply chain and in this case this tank only fits supercharged models. The normal ex-Jaguar price is around £105, less any discount you can obtain by showing your JEC membership card. Always do a parts search before commiting to buy from any particular dealer. My tank came from Taunton Jaguar via ebay for £72 delivered....so I was obviously very pleased. One might assume dealers perhaps order parts for their own use or that of a customer. Some may not collect an item, which then gathers dust on the stores shelves. If the dealer stores man has some savvy, he then attempts to knock the unwanted part on on ebay or a similar internet site in an attempt to claw back some money. My little win came just as a result of typing C2C41300 into Google. Five minutes later, the tank was ordered and paid for. Job done...... everybody very happy.

This is a general view of the tank. The stub pipe from the intercooler circuit is at the nine o`clock position and is the part of my old tank that has been causing the leakage.

This is the intercooler flow pipe detail. The very abrupt change of cross sectional area ie tank/pipe does not help long term tank longevity and these tanks and even those on NA models right across the Jaguar product range, are well known for breakage or disintigration of these pipes. So go very easy if you have to take one of your pipes off your header tank whatever Jaguar model you run. The pipes can become incredibly brittle given age, heat and high mileage.

Ideally, having fitted this new tank, I`d rather like to see if I can cut off the leaky pipe and drill and tap a thread into the old poly prop tank at that point. The remaining 99.9% of the old tank is in great order. It is sad that the old tank is in generally in such fine condition and unless a repair can be effected, it looks as if it will be scrapped. It strikes me a small threaded brass hose nozzle could be screwed into the tank and a repair effected. Thats a job for a few idle moments.

I`ll be fitting the new tank shortly and will post images of the work being done at that time.

Mike

[J44EAG]

New tank fitted this morning....not before another bit of stub pipe fell off. This old tank was living on borrowed time. Best advice then must be to get a new tank before your old one disintegrates.

Here is the detail of the disintegrating header tank stub pipe. In this case it is the return from the engine coolant circuit.

Here is the detail of the new header tank stub pipe. In rather better condition I think you will agree.

The removal sequence is to remove the 8mm bolt securing the tank to the car. Move the tank to the right which allows two molded lugs on the tan to come away from the chassis. Pump out the tank or drop the tank contents into a tray below the car. (This assumes you have the under tray removed as indeed I have.) Salvage the coolant for further use.

Reach underneath the tank and pull off the low fluid level sensor plug on its cable. Take a pair of long nose pliers and pull a silver horizontally mounted U-clip to the right on the tank lower hose arrangement. DO NOT DROP THE CLIP. STORE SAFELY. Separate the lower hose from the tank. Remove the old tank from the car. Fit the new tank and reconnect the lower hose and re-insert the silver clip into the horizontal slot. Take care NOT to drop the clip. Pull on the lower hose to ensure the hose is properly located on the bottom tank outlet. Push the new tank to the left to engage mounting tangs. Refit the 8mm bolt and fill with coolant. Check for lower hose leaks. Open the bleed valve on the tank with the ignition key in the first position. The inter-cooler pump should run and eject a solid stream of coolant from the bleed valve. Switch off ignition. Top up tank with further coolant as required. Bring engine up to normal working temperature and squeeze the top rad hose to evict any air in the system. Screw on header tank cap and take for a run. Keep an eye on the temperature guage. Open bonnet and once again check coolant level. Job done.

The above header tank advice applies to all Jaguar models. As said, replace your tank if you have any sign of disintegrating stub pipes or other header tank defects.

Mike K

[cybercontroller]

I attempted to change mine on my XJ8 but could not access underneath to get to the sensor or the other pipe connected. It looks like I need to remove all sorts of other parts to get to them or having to access from underneath. So I am now trying to find somewhere reasonably local to change it as well as an Interim service. One independent I still am waiting on to come back to me for a date. I tried a Dealer in Watford who seemed to have no idea but would ask their service department to call me back but no one did. So are they any other good places near Harrow who will do the job and not charge a fortune? I am worried that by the time I find someone, the battery will have gone flat.

[J44EAG]

That is unfortunate.

Once the 8mm bolt is out, you should be able to lift up the tank. The sensor on the tank just pulls out. The clip on the bottom hose is then easier to tackle once the sensor plug is disconnected. Lift the tank up further and grab a pair of long nosed pliers. The clip is in the 3 0`clock position. Push the pliers well into the clip and pull sharply to the right. DON`T drop that clip! Once the clip is in in your hand, store safely. Then wriggle and push/pull the hose connector off the tank. Lift the tank away from the car. Time taken for the job....about half an hour and that was with me learning how the tank came out!

I grant you the replacement of the bottom hose to the tank is a tight fiddle. Put a smear of Vasaline on the pipe out of the tank. The hose connector should then slide on quite easily. Replace the easily dropped clip. Listen for the click as the clip slides all the way home. Then just push the sensor plug onto the tank. Replace the 8mm bolt and the job is complete apart from replacing the coolant and then burping air out of the system by squeezing the top rad hose once the thermostat has opened. Top up as needed.

I take it we are talking about an X350 V8 rather than the earlier X308 model?

Why not contact Swallows at Ruislip if you really are stuck. Not used them personally but I believe they are also the same company that operate off the A38 just south of Weston-super-Mud. Here is the link to their site..https://www.google.co.uk/url?sa=t&rct=j ... r1GMB7Pq5s

I can also recommend the larger than life Tom Lenthall at Finchhamstead. He and his great guys did all the work I could`nt or didn`t want to do when I first acquired my XJR. Highly recommended. Tom and the boys have seen it all!

Hope that helps.

Mike

[cybercontroller]

Thanks Mike. Yes, X350 4.2 engine.
I figured that after pulling to the nearside after disconnecting the pipe to the broken bit and unscrewing the bolt, it should have lifted up for access but it did not. I was not inclined to try and force it too much for fear of causing more damage. Hence the decision to find someone to do it.
The independent came back this evening and I can take it over Monday evening so hoping all be done by Xmas. If all else fail, I may look to Swallows though.

[J44EAG]

Sorry, forgot one other detail.

Once the bolt is out, slide the tank to your right. The two vertical tangs on the tank will then disengage from two slots in the bodywork....then you can lift up the tank!

Mike

[cybercontroller]

It did slide to the right as far as I could get it but would still not come out.
Still took over this evening so will hopefully be done in the next couple of days.

[cybercontroller]

Picked up last night and filled up with coolant this morning and will see how we go. Hoping for plenty of use over Xmas.

[J44EAG]

Any idea why the tank was obstinate?

Mine has to come out again. It appears the auxiliary heater pump has failed. Unit is located about a foot below the tank. I might as well change the engine water pump whilst I`m at it. I have one in stock. I prefer new components on a fourteen year old car! A job for after Christmas.

Mike

[cybercontroller]

Not sure why I could not remove it Mike, although I have had to refill again last night so wondering if there is perhaps another leak. Hoping not the same problem as you.
I did get a fairly got assessment of the car.
Front pads getting thin but all right for now, rear pads fine
Both the radiators are showing their age and potentially replacement in the future.

Found out the external thermometer is faulty as it is giving a reading of around -30. With the recent temperatures, it could have been for all I know. How easy is that to replace?

[J44EAG]

A quick answer. Probably accessible with the front bumper cover off. Others may have first hand experience of removal or installation.

Google key word search inputs are always worth doing with any technical queries. Much about our cars can be found here on this site but will obviously not always be exhaustive. Together, we can usually find answers to the majority of questions.

Mike

[cybercontroller]

Quick update, after too many refills of the coolant, took back and the water pump was leaking as well as the thermostat housing being cracked. This had been held together with sealant which had now started to give way. So both replacement and after a half litre fill up I am hoping all is good to go.
Of course, I will continue to watch the coolant level like a hawk.

[J44EAG]

It is very unusual for the 4.2 water pumps to fail. The early 4 litre XK8, X308 and S-type had water pump issues. The plastic impeller could break up or slip on the drive shaft.....hence the improved metal impeller 4.2 unit was the unit to replace it with. Certainly this is the first time I`ve heard of a 4.2 unit giving problems.

The thermostat pipe/mounting unit doesn`t normally give issues. It usually appears to have a good long life.

Could it be the car has at some time taken a smack on the nose? Any evidence of a new grill, radiators or panel damage around that area?

Mike

[cybercontroller]

Well after initial good signs, I had to top up the coolant again this morning. It had again dropped just below minimum.
Strangely, after a couple of twenty mile round trips last Friday, the level was still at the same level as I had filled it to previously. Then after my round trip of fourty miles yesterday, it had dropped. Will check again tomorrow morning before I go to work.

I still have the removed items in a box which I was going to photograph before disposing of.

[cybercontroller]

As far as a frontal end whack, I really cannot say. Aside form age related scuffs, I cannot see any evidence of frontal damage. However, surely any issues arising would have occurred far nearer the time of the damage.