XJS Repair Guides

A picture is worth thousand words.
I am a busy man. You won’t find any excessive descriptions or guides below. Most relevant information only. Unless I'll get extremely bored, or retired. I was trying to find similar photos across the Internet when attempted to strip old banger for the first time, so I believe those may be useful for newbies or people willing to perform their own projects. If you’re stuck – please drop me an email – I’ll try to help.

jaguar xjs sump tank ring spanner

Jaguar XJ / XJ12 XJS Fuel Sender Ring Spanner - 3D Printed!


Did you know that 10% fuel smell in the trunk of Jaguar XJS, XJ40 and XJ6 is caused by single element? That’s correct, simple, same element used in both fuel tank and swirl pot (sump tank) – a rubber gasket and locking ring - designed by Jaguar engineer who was purely inspired with the undiscovered meaning of “marmite motorway” and “cucumbering”. Everyone knows it, everyone tried it. As always, the equilibrium is placed in application and correct tooling – not in improvisation. If you think that taking out and reinstalling is dead easy – have a full read. And yes, remaining 90% is rusted through...


Jaguar XJS Radius Arm Removal: Separator tool


Here it is, Jaguar radius arm removal subject one more time, almost impossible task for regular mortal, unless you have a separator tool wort £7.49, angle grinder and some imagination.


Yes, there is a simple tool that can be made at home and allows effortless separation on decade-old radius arm large bushes from chassis mount, even if your XJS is usually parked on the sea side. 


Jaguar Xjs brake piston blueprint

Jaguar XJS Rear Brake Caliper Piston – technical drawing


That’s right, a simple thing out of your reach across the Internet. A technical drawing of the part that caused you sooo much trouble. So, here’s the deal, you can have this technical drawing, you can use it, however it is protected by copyright. 


You must keep it as it is, no changes allowed. No copy out of copy. You don’t need to, but it is highly advisable to read further for more information how to make one, which material you should use and other crap…


Jaguar AJ6 3.6/4.0 Engine: Head Gasket Delusion


Nope, this is not an article about head gasket replacement. This article is made to help delusional people spend their money in the right way (f.eg by hitting “Donate” button in the top right corner of this website). Regardless of the fact who’s your mechanic, how good opinion has your car workshop and how advanced diagnostic tools it is using. You may be spending fortune on something that is not needed and will never be the same as made by factory. It will be a short one – promise. 



Jaguar XJS/XJ6/XJ40 Alternator renovation guide - Bosch 115A


Weird noise on engine start-up – often confused with timing chain tensioner, rough idle and jumping needle of the charging gauge. Squeaks, ghosts under your bonnet These are main reasons to look closer at your alternator. Better now than later…


This guide may look like some savings done on the reanimation of the corpse. Certainly - it is opposite. It will cost you few Pounds Sterling. Just mentioning since this is probably unacceptable for typical British Jaguar Lover. 

If you are willing to do this right and do it yourself - worth having a read. 

It will be better, it will be reliable, it will be made with your own messy hands. 


Jaguar XJS 3.6 and 4.0 Engine Resurrection Guide


Willing to buy Jaguar "Barn Find" XJS project? Something that wasn't moving for decade? Tell the seller "DON'T TOUCH IT!". Save plenty of money and resurrect it in the right way. Timing chain, cylinder head, bottom end bearings, cam shafts, valves, water pump. these are only few things that may fail after long nap... AJ6 engine is solid as rock, probably will start up without a problem after 20 years of sleep, however doing so instantly - you will probably cut the 100.000+ miles from the engine's lifespan. The choice is yours. 


4hp22 Jaguar gearbox

Jaguar XJS Automatic Transmission Start-Up 

(after long sleep)


Unfortunately, apart from the engine - there is one more thing at risk of damaging when starting up after long time not in service. Damage that can occur is absolutely stealth and may cause a big surprise to your wallet at any time in the future. This guide is simplified and easy to perform. Is it worth spending some time to go through it. Hell yes. 

Jaguar XJS – Parasitic Battery Drain – Final Resolution.


After three decades of assumptions, theories – we are finally here. If you’re reading this – it means you probably have solar trickle charger installed in your XJS-crap already. You’ve tried all the tricks and it doesn’t work…  Frankly, the ISO/TS 16949 standard for quality management systems – was published first time in 1999 leaving no appropriate quality records for those amazing British cars until the last day of production. But hey, German Bosch wasn’t better – even if admitted to cock-up and rushed by their customer “JUST GIMMIE THE PARTS” – agreed for those to be delivered and assembled. A dodgy batch they say. Automotive Electricians are going to hate me.




Sagging Headliner - Ultimate Solution


Yes!!! It was finally invented. No bull. No need to remove it. It’s cheap, It’s permanent and won’t go down during the hot summer. It will stay undisturbed with heater blower left shut overnight inside - while you’re trying to dry 2-tonne swamp of classic damp. It will last the joy ride through the HELL.



Jaguar XJS Seized Brake Piston Removal


Simple tool to help with your misery during Jaguar XJS brakes restoration. I paid £8.65 on eBay and I made it to fit M8 slide hammer. You can make your own one – don’t suggest yourself with piston’s internal dimension - check those in your brake calliper. These were manufactured over the last 30 years by multiple manufacturers – mostly due to masochistic demand in UK also known as “The Flintstone braking, mate”. This is an introduction to the World! Not seen on any Jaguar Forum so far…



Jaguar XJS Rear Quarter Glass Surprise


You are absolutely right – who would have an idea of removing rear quarter glass without a reason. It looks ok, who would be willing to touch it… Maybe breaker but not the owner, not in UK. There may be an important reason to do so. But why??? The answer is: challenge. If you want something to scare the shit out of you, if you want to look like Winston Churchill visiting bombed Coventry in 1941, if you are willing to discover from where Guy Fawkes puked while getting drunk at The Bull Inn – help yourself and remove the rear quarter glass in your shiny, classic, admirable Jaguar XJS. Alternatively – plan, prepare and do it, hoping it’s not too late. 



Jaguar XJS (every car) Brake Accumulator Testing and Replacement Procedure

Jaguar XJS (every car) Brake Accumulator Testing and Replacement Procedure


There are dozens of scenarios and legends about checking condition of your brake accumulator. Unfortunately, most of them are misleading, and worth a quarter-pounder with bull’s droppings. You can stick your straw, you can count the seconds, but without understanding – you are wasting time. Don’t spend £250 to replace the accumulator’s sphere if unsure what’s actually failing in the brake system. Have a read, check before buying new one. 


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