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How easy is it to service the engine on a V12 XJS. Plugs, oil, filters etc
Thanks
Jeff

Jeff

Shame you weren't able to attend the XJS Seminar last weekend, all your questions would have been answered

Never Mind.........for what it's worth be VERY careful if changing the front spark plugs (under the air-con compressor). These are very easilly cross-threaded. You may wish to unbolt the compressor and move it forwards (still attached to the hoses) towards the radiator to give better access - better than stripping the threads in the heads.........

Also re changing plugs, be aware that there will be all sorts of rubbish trapped within the V and especially down in the spark plug reveals, so, blow out around each plug with an airline before removing it and only change one plug at a time - this will avoid dirt, washers and any other ancient detritis, etc. etc. dropping into the cylinders and causing very expensive damage.

Don't bother putting expensive synthetic oil in, go for a good quality oil but change it every 7,500 miles or six months. I would recommend a genuine Jaguar oil filter.

Be aware that there are all sorts of suspension grease nipples under the car (depending on year) that will need attention, but the car needs to be SAFELY raised to attend to them.

Other than that, read the book carefully and Good Luck

DH Dove

Jeff,
if your car has the Marelli ignition (2 amplifiers on the radiator cross-rail and 2 square coils) then your life is a bit easier as you don't have to worry about making sure the distributor advance mechanism is moving freely and lubricated as yours is done electonically by the engine management system.
I do my own servicing and the tips I'd pass on are
1. Allow plenty of time, ie a complete weekend to do the whole service (this is not a family hatchback!)
2. Remove as much as you can from the centre V to give good access to the plugs so that access to the plugs is as easy as possible. If you make it awkward you'll stand a greater risk of crossing the threads when you put the the plugs back in. Take out the cruise control bellows, unbolt the air-con pump and move it forward, take the distributor and leads out etc.
3. Blow each plug hole out before taking the plug out so no crud gets into the cylinder.
4. Make sure you get the right plugs with the taper head and DO NOT overtighten them (Pre HE plugs have square ends)
5. Make sure you get the right air filters so that the flash guard is opposite the manifold intake. If you have the Marelli ignition then you need the later type. Sorry - these are more expensive but necessary.
6. It's fiddly to get the plug leads back on but make sure that they are on properly or it'll drive you mad trying to find the mis-fire!
7. Check the state of the the distributor rotor - these can break down and short out leaving one bank of cylinders dead (on Marelli cars).
8. There's no need for fancy synthetic oils etc. I use a 20/50 semi-synthetic for the summer months when I'm using the car and a cheaper 10/40 for when the car is laid up over the winter and only gets started up every few weeks.
In summary, it's not impossible to do your own servicing, you just need time, patience, a reasonable tool kit and a bit of knowledge.
Good luck!!!

ThanksGuys