Question relates to my XJS V12 1987 rhd UK model.
I am about to try and clean out the filter chamber under the battery and it seems quite straight-forward. I have removed battery, fuel pump cover, all carpets, spare wheel etc from the boot. I have checked with a few comments on the forum and think I follow the logic. However, the repair manual tells me I should first depressurise the fuel system by disconnecting the connection to point 85 on the fuel relay (the orange lead?) and the HT lead on the coil and then turn the engine over a couple of times to depressurise the system. I can then unscrew the plug under the fuel filter chamber and empty the tank. Am I right in following this path to emptying the tank? Many thanks for your guidance on this and know for many of you it is quite basic but I'm more used to cars a lot simpler to manage and without pressured fuel systems.
Do you reckon my local Jag dealer here in Belgium will have a replacement rubber seal for the fuel filter chamber as I note that it should be replaced (it's definitely been on there since 1987!). Anything else I should consider replacing at the same time?

 

I wouldn't worry about pressure to much if the car hasn't run in a while... The sump tank is gravity fed and I believe there won't be a lot of pressure until after the pump - put some duct tape or sections of cut rubber hose over a pair of mole grips or vice grips and just carefully pinch off the hoses/lines into and out of the sump.

Under the car, if it's not completely crusty and locked up, there is a drain valve covered by a 1inch rubber body plug - on the under side of the boot floor in the corner directly under the sump. Sometimes you can get a socket in it and drain it from underneath. It holds quite a bit of gas so have a big catch basin of some sort...

 

As Jason mentioned.

Drain the fuel tanks from that drain spigot under the car, it will drain ALL the fuel, as in both tanks, so be prepared.
I always syphon the main tank via the filler spout before doing that, as too much raw fuel sloshing around under the car is too dangerous, even for me.

The seal is the same as the tank snder seal, and most tank sender unots are the same size, so the seals are the same. I used a Ford one on mine waaaay back, coz Jag were out of stock Aust, normal.

Order 2 from David Manners in the UK, Jack is the man, mention the Forums, he is good at what he does.

By the time you get it all cleaned and ready to assemble, those seals will arrive.

CAREFULLY inspect teh fuel hoses, gravity and pressure, and rep;lace is in doubt.

I agree also with Jason, if the car has sat for 24 hours or more without the Ign being turned ON, there will be near zero pressure in the Hi side anyway.

 

Since it hasn’t been specifically mentioned yet, there is a filter in the swirl pot. Originally a small metal filter, later upgraded to a large plastic one. Get a new one of the plastic ones and install it while you’re in there.

 

Many thanks guys for your advice. Will have a go at draining the tank. I drove the car out of the carport a few days ago so the fuel tank has probably depressurised by now. I have a few large petrol cannisters and even if I fill those I can always put the excess into one of the other cars on the drive (after filtering). Will let you know how it goes. There is currently a bit of a problem getting spare parts delivered to Belgium from the UK at the moment. I had a parcel arrive yesterday that was from an order from 10 April! Something to do with being held up for paperwork by UK customs following Brexit. Hopefully, a couple of seals sent direct from Manners might be quicker although the Belgian Postal system have now put a special additional tax on goods received from outside the EU of 24 Euros. So those seals that cost a couple of pounds might end up costing an awful lot more than that. I will see whether I can get hold of some through my local Jag dealer before resorting to the UK.

 

Hi Guys
Just to let you know I eventually managed to extract the swirl pot. I spent a couple of hours wielding a 5/8 AF spanner only to eventually discover it needed a 11/16 (after first trying 17, 18 and 19mm). Needless to say, the nut was not centralised in the access hole but with a bit of loosening of the bolts holding the chamber in place I managed to get a socket on and everything was easy after that. Didn't realise there was 60 litres of fuel still in the tank but thankfully I was able to redeploy it among a couple of other cars. The biggest disappointment was finding that there was very little dirt in the chamber and the plastic filter was pretty clean. Before I put it all back together again I was wondering whether that plastic filter was supposed to be fixed somewhere. I found it floating around loose but I would have thought it would have fixed on one of the inlet or outlet pipes? Can anyone clarify for me please?

Next job is to fix the leak in the exhaust system between the front down pipe and the intermediate pipes (non-cat model). I can find some new stainless steel pipes online but knowing how stubborn then bolts on the clamps can be I will probably hand over to a garage. I did notice that someone had taken a welding machine near to the rear joint to the silencer box on one side. Will give my local garage a shout and see what the best way forward on that little problem is.

 

The open end of the plastic filter slides up the outlet tube. If it will not stay there, get a new one.

 

I love my Jag but some of the design/engineering is unusual at best!

 

As Homer Simpson would say "Doh!" Of course, it slides on the inlet pipe. Why didn't I think of that? Thanks Greg. Now to find a rubber seal here in Belgium. Must be somewhere that has one.

 

Just a quick question - hopefully the last for the time being. The sealing ring has arrived today and is now fitted. As I am putting it all back together I notice a small rubber drain tube that does not appear to be connected to anything. It exits the car via a hole just under the fuel pump but I am lost as to where the other end belongs! There is a second tube from the battery tray that is in place so it is not that. Any ideas? It is long enough to reach the bottom of the petrol tank. Can take a photo if it helps.

 

This is a battery tray fumes from the battery drain tube. Under the battery try you will find a spigot!

 

I've attached a couple of photos showing (a) the battery drain tube still attached and (b) the spare tube that exits via another hole just under the fuel pump. I've removed the filter chamber to see whether there is a spare spigot but I haven't found anything. Any more ideas anyone? Presumably it is taking condensation from somewhere?

 

Simple.

Some newer batteries have a breather hole in the side, with a 90deg elbow, to which is attached THIS tube, and the fumes from the battery are vented out through the boot floor.

I suspect the installed battery has not been connected to the vent tube.

 

time for a Lithium battery?

 

Thanks. That makes a lot of sense. Surprised that Jaguar thought of such a thing so long ago!
Onward and upward. Just need to fix the intermediate exhaust sections now. Hopefully, that is a bit easier.
Thanks again for all your help.