Just purchased a 1986 XJS V12 and wanted to do whatever preventive maintenance I could before I get it out on the road.

Any advice out there?

 

Congratulations! The XJS is a beautiful car that is a superb driver. Pictures!

Engine is nearly bulletproof. Cooling sytem, climate control, electrics, and various rubber parts throughout the car less so.

Yes, lots. Almost 1000 pages in fact:

Kirby Palm's Jaguar XJ-S Help Book

Unless a previous owner overhauled your distributor, I can tell you that it is seized.

Stock coolant system is challenged but adequate. If it hasn't been maintained well you could be looking at a radiator change/recore. Chronic overheating is the death of the Jag V-12.

Plus all the usual stuff regarding keeping fluids fresh, etc.

Cheers,

- Will

 

Unless records prove otherwise I'd assume all routine services are overdue and knock 'em out 'em out in one fell swoop:

-Change all lubricants. Engine oil, trans oil, differential oil
-Flush brake fluid
-Repack front wheel bearings
-Replace fuel filter
-Thorough visual inspection of hose, belts, brakes, tires, suspension


^ That's all standard stuff that you'd do on any car.

On a Jag V12 you'll want to replace all the fuel hoses in the engine bay - injector hoses, feed hoses, return hoses -- unless they've already been replaced in the last 5 years or so. This is important!

If you change the injector hoses you're in a good position to carefully inspect the engine wiring in the area as it'll be baked and brittle.

To be honest, I recommend "cleaning the Vee". Remove the fuel rail, distributor cap and plug wires (which you might wanna replace), cruise control bellows for *easy access* to the spark plugs and all the injector and ignition wiring....as well as all the vacuum hoses.

Check that the distributor mechanical advance hasn't seized (they usually are) and that the vacuum advance still works (they usually don't)

If the car still has the original coils they're certainly on borrowed time so you might consider pre-emptive replacement with the updated DAC6093 coil. Same for the ignition module, AC Delco D1906. Carefully inspect all related wiring.

One of the best things you can do to keep your 26 year old Jag reliable is to clean the battery cable ends and check/clean/tighten every electrical connectiona and ground point you can put your hands on. Doing so will eliminate 80% of the "Lucas wiring" horror stories.

Lastly, the cooling system. If there is the slightest doubt as to the condition of the cooling system you need to jump on it. This is very important. Clogged radiators are common as are incorrect thermostats, weak fan clutches, and inperative aux fans.

I know this seems like a huge list, and it is, but virtually all of the XJS problem areas that can make the car unreliable, and the fixes, are well known. You can tackle 'em all at once and be good to go for years or torture yourself and do 'em alá carte :-)


Cheers
DD

 

Thank you so much for all of your help here...