Skizzer's XJ-S

[billyboy406v6]

Would be worth checking all earth connections as a first step ?

[Skizzer]

My v12 has a wee cut of trip thing on the side panel near where your right knee is when sat in drivers seat..it skinda burried away. It has a platic peg thing on the top that needs to be pulled up for car to start. I was in another v12 a few weeks ago and it had the same contraption...worth a look

 

I really hope it's this! Sounds promising and an easy/free fix. Thanks.

 

Could it be that the ignition switch is buggered?

Yup, could be, although if I'm misdiagnosing the coil thing and that is getting power then I'm more suspecting the electronic ignition or something like what Kinkersaab said.

 

Would be worth checking all earth connections as a first step ?

Ah, you're right of course, but you say this like it's an easy thing. I've had a go, but heaven only knows how many earth connections there are in that giant rat's nest.

 

I love these cars and did consider buying one a while back but the thought of constant problems I couldn't fix myself kept me at bay.

I like to be able to fix everything myself so keep to much more simple cars, sorry this doesn't help,with your problem but great to see somebody having the balls to run these especially in V12 version.

#Sigh# You are the voice inside my head that I really should have listened to all along. Mind you, I've got a Vauxhall Victor I can't fix either, so clearly they haven't yet built a car simple enough for me. I might as well be hanged for a sheep as a lamb.

[Skizzer]

I will do more investigation tomorrow. Out today, collecting more broken car.

[SiC]

Mind you, I've got a Vauxhall Victor I can't fix either, so clearly they haven't yet built a car simple enough for me. I might as well be hanged for a sheep as a lamb.

Trabant?

 

Your XJ-S looks a lovely motor. They don't build them like they used to! (Probably a good thing...)

 

Probably something silly simple (just buried away).

[Guest Hooli]

That cutout thing cuts the fuel in the event of an impact as far as memory serves.

[AMC Rebel]

I knew a bloke with an XJS - it was newish at the time, but this was in the 90s.  it cut out on the motorway and he claimed the rotor arm had failed - no idea if it's even true.

[Bear]

I knew a bloke with an XJS - it was newish at the time, but this was in the 90s.  it cut out on the motorway and he claimed the rotor arm had failed - no idea if it's even true.

 

 

On a Marelli car, yes, totally plausible - they've a double-deck rotor that splits and arcs across. Worst case scenario, you lose a bank on the engine but it keeps dumping fuel in there, which says hello to a hot catalyst, and...

[Des]

I once fixed a dead 'S by soldering up a burnt track inside the ECU, the body of which had been glanced by a jump lead, clumsy, but less destructive than striking an arc on the fuel tank.

[Braddon81]

I'd have thought with this being an 83/84 it would have the Lucas ignition set up.I would hazard a guess that the next port of call would be to examine the ignition amplifier module and also the condition of the wiring which exits the dizzy to the ecu which can break up. Inside the module there's a condenser type unit which likes to play silly buggers at no ungiven notice and cause non start symptoms, thankfully it is replaceable without having to change the complete module.

[Skizzer]

I have been slack at updating this. I hope the suspense hasn't actually killed anyone.

 

I've been away in London all the hours that most garages are open, so finally a mate took pity on me and my non-functioning Coventry cat and had it recovered to our friendly local Jag specialist (Mister Matic) on my behalf.

 

They've been through all the things I went through:

- cleaned the contacts

- fuses

- coil

- rotor arm

- dizzy cap

- ignition amplifier

- ignition amp capacitor

 

and they can't find the fault either, so they've given up (with my complete blessing as I'm in no rush) until after Christmas. They agree with my conclusion that it's a dodgy connection buried deep in the under-bonnet stork's nest somewhere, which is gratifying I suppose.

 

Being an early HE it does indeed have the Lucas ignition, which is at least less complicated than the weird double decker Marrelli set up but still everything seems to be wired in parallel which quickly defeated my very limited multimeter skills.

 

Mister Matic are very good people so they'll find it eventually. In the meantime it's tucked up safe and warm and I don't have to spend every weekend digging it out from under a drift of dead leaves.

 

I'll probably get them to do some other jobs too: something is still rubbing at the back (brakes?) and the fuel gauge doesn't work (probably sender). I'm sure there was something else, but I haven't driven it since David Cameron was in power so I can't remember what.

[Skizzer]

An update:  Good news is, they've found the fault!

 

Bad news is, the cast iron distributor driveshaft has snapped.  Not the shaft inside the dizzy, the one inside the block that drives it.  This is apparently a very rare thing to happen, which is lucky*.  The car was 'running fine when parked', to coin a phrase, so the shaft must have cracked on cooling down after a heat cycle. Fortunately there doesn't seem to be any other damage - nothing has seized, valves aren't bent.  

 

But you can just imagine how much de-plumbing and disassembly is involved in getting to that and checking for ancillary damage:  the radiator and the timing chain have had to come out for a start.  Still, while they've got everything apart I've asked them to renew the chain tensioners and the water pump, and it needed a change of oil and coolant anyway.  The timing chain is apparently in good condition.

 

I'm in no rush to have it back so they'll fit it in around more urgent stuff.  Should be back in a couple of weeks.  Gives me some time to save up for the non-trivial bill.

[Magnificent Rustbucket]

I am a slightly amazed by this!

[Junkman]

Weirdly the majority of electronic* problems appear to be caused by mechanical failure.

I know exactly why I'm so scared of Jags. In a proper car, i.e a Rover V8, changing that shaft would be a pip.

[Skizzer]

I'm scared of this Jag because under the bonnet is so completely crammed full of engine and stuff.  The sixes aren't nearly as bad, though.  

 

A carb-fed V8 SD1, meanwhile, has enough room under the bonnet to smuggle over a couple of small Albanians, maybe three if you remove the enormous air filter that's made out of an old oil drum.  The P6 would be exactly the same if the space wasn't occupied by perversely configured front suspension.

 

 

TL/DR:  I agree.  But I am gently lobbing back the ball to you in our occasional game of P6 vs SD1 tennis, because you said my XJ-S was improper.

[chaseracer]

Chilled-out Umpire Guy says: DEUCE!!

 

[Asimo]

Weirdly, I earwigged on a "really interesting conversation" about the V12 engine's jackshaft, between two engineers in a Coventry pub. It turned into a pretty loud argument; one chap clearly worked at Triumph the other at Jaguar and the jist of it was that such auxiliary shafts are an added complexity that makes an engine cheaper to make.

[Guest Breadvan72]

As I have mentioned before, the V12 in a Jag looks like the chemical refinery that the spaceship was towing in "Alien", and may be just as likely to harbour terror and destruction.   You don't even get Sigourney Weaver in emergency space pants as a bonus.  

 

 

[Skizzer]

^ That is exactly what it looks like.  When I get the alien craft car back I will post up a photo to prove it:  I haven't been brave enough to take one so far.

 

(If I can also score a photo of Sigourney Weaver in pants then I'll post that too.  John Hurt, maybe not so much.)

[Junkman]

I'm scared of this Jag because under the bonnet is so completely crammed full of engine and stuff.  The sixes aren't nearly as bad, though. 

 

Yeah, but.

People have hitherto failed to explain to me the point of a Jag with merely half the achievable cylinder count.

 

So philosophically, I'm more than prepared to share your misery.

[Cleon-Fonte]

Undoubtedly the best* solution is to tear out the V12 and put in a Rover V8 instead.

[Junkman]

Undoubtedly the best solution is to tear out the V12 and put it in a Rover V8 instead.

 

FTFY

[spartacus]

 

Here you go...

[Guest Breadvan72]

What is it with space shreddies being so impractical?.  Poor Princess Leia had a lot of gyp in that department.

[barefoot]

What is it with space shreddies being so impractical?.  Poor Princess Leia had a lot of gyp in that department.

What is impractical about those? I could slip them over to one side with relative ease.

[BorniteIdentity]

 

Here you go...

 

MOUND!!1!

[Skizzer]

An update: Good news is, they've found the fault!

Should be back in a couple of weeks.

Ha! Okay, so it's been a bit more than a couple of weeks. Still, it now runs happily and has had all the belts n fluids n stuff done, and the interim bill was jolly reasonable considering.

 

Have a picture of the broken jack shaft:

 

Work continues, though. Attention has now moved to the gearbox, which has the wrong actuator on it which is causing it to change down at inappropriate moments. I thought all autoboxes were like that (except mk2 Granada V6s) but apparently not. Some bright spark has glued the gearbox sump on with bathroom sealant so that's all had to come apart and get de-siliconed.

 

The steering rack is leaky and the bushes are knackered which explains why the steering is so vague. Again, having read all the OMG NOT A SPORTS CAR XJ-S'S ARE SHIT M8 bollocks I thought this was just part of life but apparently not. So a recon rack is going on plus some nice firm bushes (no more Sigourney jokes please).

 

I'm excited about getting it back soon, it sounds like it's going to be a much nicer thing to drive. And it wasn't that bad before.

[dollywobbler]

Ace. KWE reckon that polybushes for the rack improve things no end. There aren't many places they'll recommend plastic, but that's one of them.

[Skizzer]

As noted in the grin thread, the XJ-S has now returned home after (shockingly) a two year absence being fettled. Fortunately that’s not two years of continuous full time work, but it’s had a lot done.

 

Steering rack replaced and steering rebuilt.

Broken jack shaft replaced and timing chain tensioners replaced.

New alternator.

New distributor cap and rotor arm, twice (because the Intermotor one I got was crap).

Gearbox actuator replaced and sundry other transmission sortings out. That was a bit of a war because the gearbox sump had been stuck on with bathroom sealant.

New heater blower.

Various works on the rear brakes, can’t remember exactly what, but they aren’t stuck on any more. Caliper refurb I think.

 

Long story short, it’s transformed the car. Where before it felt tired, baggy and liable to fall off its perch at any moment, it now feels smooth, planted and ready to go to Monaco for lunch.

 

It’s incredibly smooth. You can’t hear the engine at idle. You can feel a tiny vibration but otherwise it’s a leap of faith that it hasn’t stalled. It responds to the throttle with a muted, distant roar and suddenly you’re doing 80, though it doesn’t feel it. (And probably isn’t, as the speedometer seems fairly optimistic.)

 

The ride quality is exceptional. You can feel small bumps like manhole covers, but the overall impression is of floating. Larger undulations are simply absorbed, much as the QE2 used to dispense with a Channel chop; you can drive over raised pedestrian crossings without slowing at all, if mpg in the mid-teens isn’t sociopathic enough for you. Traffic calming? I’m perfectly calm already thank you, almost to the point of serenity.

 

 

The steering is still very light, perhaps excessively so at speed. It does go where you want it to, but there’s not much feel; it’s quite American somehow and very different (unsurprisingly) from the Lotus Elite, say.

 

Now there’s an interesting comparison. Two very different approaches to the luxury GT; the Lotus cost 25% less when this car was new in 1982, and had one third of the cylinder count but similar performance. It’ll be fascinating to drive them back to back... in the brief window while both of them are working.

 

 

By the way, that new Charles Wright front number plate was needed for the MOT. It won’t be staying long.

[BorniteIdentity]

I hope you have an immense sense of satisfaction driving it around, having been so patient - and - understanding with your wallet.

[BorniteIdentity]

Parklife