Hi

In my garage, I have a 1989 XJS V12 5.3 (70,000 miles) which hasn't been started up or even turned over in 10 years.

But now I want to fall in love with this car all over again!

My problem is one of how should I start or try and start her up?

As you can imagine there are different schools of thought on how this should be done and all except one are from people who know very little about Jags.

So here is some of the advice that I have been given:

(1) Just put on the battery, turn they key and hope that after a good few spins the engine might burst into life!

(2) Take out all the Spark Plugs and then squirt some WD into each cylinder, then spin her over a few times, replace the plugs and hope that she will start.

(3) (From a Jaguar Expert) who said he had heard of V12's dropping valves. Not quite sure what he meant but that made me feel nervous!

His advice was to remove all the spark plugs, then give all the cylinders a squirt of very thin oil or WD then turn the engine over by hand with a spanner on the crankshaft.

Then replace the plugs and spin the engine on the self starter and then it should hopefully start.

The Car is near a wall on one side of the garage and because of some immovable obstructions, cannot be towed out into the open.

So it would be very difficult but maybe not impossible to get the plugs out, which is something I hate doing as I am absolutely paranoid about getting a plug cross threaded when I put it back.

Not to mention one of those plugs is a real pig to get to and so may have to be left in.

I would love to put the battery on and spin it and hope for the best, as I don't like disturbing the engine (if it ain't broke don't fix it and all that)

But am wondering what would/could happen if the bores were dry.

Has anyone any experience of starting a V12 XJS that has been laid up this long as I don't want to wreck the engine through doing something stupid.

 

2-3-4 years id throw a battery in it and try

10 years though. i would squirt a little oil in the cyl turn it over several times by hand. then disable the ignition and spin it over several times by the starter. probably sipon off as much gas as you can and put some fresh fuel in it and then put the plugs back in and give it a go.

doing it that way will help clean up and loosen any internal rust from condensation and pre-lube everything before fire up. then after running the motor a little bit full fluid changes would be in order.

 

Personally I would remove the plugs and give each cylinder *several good big squirts* of light engine oil. Let it sit for a day, then turn the engine half a turn or so, let it sit, repeat, repeat. After a few days 'bump' the engine on the starter to eject any excess oil. Reinstall plugs, drain/pump stale gas and add fresh gas, new fuel filter, give 'er a whirl and see what happens.

After 10 years the car will need quite a bit of rehab work

Cheers
DD

 

Frankly, I would push or pull or whatever I needed to do to get it out of the parking spot so it can be towed to a shop. That way if it gets screwed up it's by a pro who should know what they are doing.

 

i don't know that i would take it to a shop unless your not mechanically inclined at all.

the biggest concern to me would, be internal rust or a stuck ring breaking a piston ring when you try to fire it up. a good oil soak and turning it over by hand several times should eliminate most of that risk. after a several day soak and hand rotation cycle i would turn it over enough with the starter with the spark plugs out to build oil pressure before you try your initial start.

 

10 years?
Personally, unless it was a barn find Cobra, Ferrair Daytona or similar then I really wouldn't waste my time.
Jags are rubbish unless they are driven regularly; assuming that you can get the engine running you are still hundreds of hours and thousands of (insert local currency here) away from having a legal, useable car.
Everything will need replacing; all fluids, filters, hoses, brake lines, fuel lines, the brakes will be seized, the tyres goosed but if you are really lucky then vermin won't have got into the wiring. And the upholstery.
Not to mention rust because our Jags do have a fondness for the brown lacework.
Scrap it, sell the bits that still work and buy another one; there are plenty out there and it will save you a load of grief in the end.
Of course, that it just my opinion.

 

Hi Catnlion

It would be 'near' impossible to get her out of the garage without her being under her own power, as it would almost certainly get scraped against the wall but in an ideal World I agree that getting her out of the garage would be best.

 

Hi Ezrider

I think you've hit the nail right on the head, as I have been in denial about the possibility of a stuck ring breaking and wrecking the engine.

So I think I am going to have to jack the car away from the wall and having got all the plugs out, give the bores a good squirt of oil and turn it over by hand.

Then once I know its running free, put the plugs back and then go for a start.

Just wondering if you happen to know what size socket I need to fit on the crankshaft.

 

I won't be doing that Steve, this car is in Pristine condition and once the engine is running will be one of the best on the road.

 

Hi Doug

I am going to have to get stuck in and do exactly that, so thanks for your input.

 

Good luck but don't say that I didn't warn you!

 

I have seen a 283 chevy that sat for almost 25 years be started by taking out the plugs and putting marvil mystery oil in each cylinder, and then cranking by hand.

Then pull the ignition wire off the coil and use the air pressure method to force oil in the engine, and crank untill the oil light on the dash comes on.
(Or use an autozone oil pressure gauge mounted in.the engine.compartment like I orignally did)

Then finally crank the engine with the with the ignition hooked up and fresh gas in the tank.
(Easiest to.use the pump and just pump the old gas out the engine compartment with an extra fuel hose)

Also don't be suprized if it blows.a lot of smoke and steam, the rings will probably have to reseat and theere will be oil in the cat.

Hope I helped in some way!

 

Hi ,just about the getting the Jag out .If it is in a really tight spot have you heard about go jacks ? They slide in under the wheels individually and then you can lift the car and move it pretty much in any direction you want and front and back can also be moved individually in any direction .Same thing most panel shops and race teams use these days and really are not all that expensive and a good tool to have .You do not have to have 4 sets as 2 will get you out of some really tight spots .You should be able to get them from any parts /auto shop chain store type place . Once you have the Jag out you can then do pretty much what you want.
Regards Mark

 

I bought my car in 2010 and it was parked in 1996 so I'll tell you how it went.

Removed all plugs and gave generous squirts of marvel mystery oil.
Rotated engine by hand a few times and gavei it more squirts next day.
Inspected plug gap and condition while removed.
Changed all fluids.
replaced battery
Removed fuel sender after draining tank and cleaned out tank and sump tank. Sitting like this ruined my tank and i will have to etch and seal it in a few weeks because it is eating fuel pumps and filters.

bumped starter a few times while putting a bit more oil in cylinders after disabling ignition.
Turned key on to listen for pump to prime and tried to start.
My engine turned over fine but quickly stalled. I repeatedly started and ran the car until it was running okay. It wouldn't rev at all. I'm not sure at the time if this was the ECU or everything being stuck in position from sitting and not feeding the engine fuel:air properly.
I had to sit with the engine at idle and gently raise RPMs by about 2-3k in a period of half and hour. I ran the engine every day after for about 30 minutes and drove it after a week of doing that and checking EVERYTHING to make sure it was all in okay condition and working properly.

been my DD ever since

 

10 years eh? I just got mine back on the road after 15, so fear not. It cost me all in all about £900 doing the all the work myself with all of the major components intact. Ignore the pessimistic comments about scraping or abandoning your car to a mechanic (a non specialist generic mechanic can actually be a lot worse than a good diy'er from my experience) Treat yourself a workshop manual, read the free XJS book available online and dive in. Its good fun!


Just a small point worth noting if you are not familiar with your engine, accessing and removing the sparks plugs is a bit of pig on the V12. Google - "Accessing the Vee" and you will see that you ideally need to move the compressor, cruise control bellows and throttle pedestal to work away in comfort. Be prepared to soak the plugs in-situ with some penetrating spray - they will be stuck in the thread like limpets - DO NOT force them, you will strip the thread and then you really need a mechanic.


When you do this you will also almost certainly want to dismantle the distributor - check both the mechanical (seized) and vacuum advances, replace the dist. cap and baked HT leads. Also check the EFI harnesses for cooking damage and repair with silicone tape as necessary, I also moved mine to the fuel rail to prevent a re-bake - a worthwhile exercise. That "should" be ignition sorted.


Then just pump the fuel out of the system (not as tricky as it sounds), swap out the coke can filter in the boot and fire her up. Dropping valve seats btw is a death blow for these engines, thankfully it is not nearly as common as people think and is relating to the temperature of the engine. But that's an entirely different topic - and probably what you will need to know about next!

Good luck

 

Ditto.. This is what I have done with numerous 30-50 year old collector cars that have sat since the 70's and 80's...

 

For 10 years? Geez man if it were up to you there would be 5 classic cars on the road today because none of them are worth restoring unless they are were hundreds of thousands...

I got mine straight out of high school and with about 500 dollars had a daily driver
Where do you get hundreds of hours and thousands of dollars?
Replace the fluids,some hoses, and stick some good tires on it and drive it. Repair problems as they arise

 

Hi Calvin

I've not heard of the air pressure method that you have described and never seen the 'Mystery' oil for sale in the UK but I get the idea of squirting some oil down the bores.

All I've got to do is get the plugs out, which seems to involve dismantling half the fuel injection system, which does look a pig of a job but I'll give it a go.

 

Hi Mark

While that sounds a nice idea, it would probably be cheaper to get a Jag mechanic to work on it in situ and then drive it out.

But I want to do the job myself as otherwise I do not think that I could consider myself a true enthusiast.

 

Hi Sidescrollin

That was interesting! and I think that I will copy what you did.

I managed to jack the front end away from the garage wall, so I could get round the 'bonnet' (hood)

Then I pulled the car covers off for the very first time since October 2005!

So She's been off the road for 8 years! not 10 as I first stated and boy did I get a shock! (But in a good way!)

I was absolutely stunned how beautiful She looked, just like She came out the Showroom!

So She is my must have back on the road car for this summer.

I also stated the mileage wrong She's only done 57,000 from new!

So I'm not about to cut corners and risk wrecking the engine.

Having got the bonnet/hood up, getting to the Spark Plugs does look a bit of a nightmare.

So any advice on what to unbolt would be appreciated.

Many Thanks for your interesting and very helpful reply.