Oops! I hate it when that happens!
One of our Jaguar engine Gurus will be along shortly to give you some helpful words.
My car has a Chevy 350 so I can't really help you with your Jag engine.

When you get a minute though, fall by the New Members section and post an introduction.
https://www.jaguarforums.com/forum/n...-intro-must-5/

Welcome to our playpen from ElinorB.
(';')

 

go to youtube and search "how to unseize engine". there are many remedies on video.

you can get to the 1 - 5/16ths crankshaft bolt by removing the radiator. personally I would not mess with trying to turn the engine with it. If that bolt breaks, forget it.

that is a rare XJ, do it right.

 

You're unlikely to break that very large bolt, but I would remove the spark plugs first before you try anything. Water may have got into one or more cylinders and you're getting an hydraulic lock when a piston rises. Despite being in a garage 17 years the engine should not be seized, When I bought an MG Midget in 2010 it had been in a garage since 1996, yet started almost straightaway.

Other thing to check is for a stuck valve.Take off the cam covers and when you turn the engine over, make sure the valves all come back up. I bent valve due to this !!

 

nice car!!!!
ron

 

I turned over my 77XJC after 18 years parked. I used a long breaker bar and the big socket. removed all the plugs and sprayed (you all will love this) WD 40 in each cylinder, let it sit for a couple of days, then pulled on the breaker bar. turned easy. Since then I have changed, fixed and cleaned a million things and then started it. Started right up. Good Luck Geneo

 

I have found that WD-40 is greatly underappreciated!
I keep several cans at the ready, everywhere from right over the dryer next to the starting fluid, to a couple cans on my work truck so I don't have to go round to the other side for one. That doesn't count 4 or 5 in the shop (out of husband's sight as he hates it) and a tiny one (2 oz.) in Nix just for good measure.

I'm looking for a Really tiny one I can put on my key ring.
(';')

 

Wrong guy, but advicxe the same. Fraser!!!!

 

SOG, this post worked. Two prior and much better ones are lost!!!

Quick reply failed? Advanced worked???


All I had to say has now been said, except two points:

1. Slacken the belts that the crank pulley drives. Reduces resistance to getting the engine to turn over.

2. Attend to the starter

A. Give it a whack/ Percussion maintenance.

B. Go over all the battery cables + and -.. Clean lubed and tight. Not to forget the one down under at the transmission to engine mating point on the right side
C All connections down under on the starter solenoid.

The engoine may be free, but the starter's ability to crank is compromised!!!

Carl _.

 

What ever you do heed the advice to remove the spark plugs first!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

Pull all the plugs and pour in some marvel mystery oil and just let it soak for a long time....like days. Then attempt to slowly try and spin it by hand from the crankshaft. Access to the bolt is probably easier from the bottom. Also do not just throw a huge pry bar at it, because what you could have is a lip on the cylinder wall or a stuck ring, and if you just go at it, you could snap the ring land. Let the oil do it's job, and always try to turn it over with the plugs removed as mentioned above. Also if it turned a little bit it may be beneficial to turn the motor a little bit in the reverse direction to allow the oil to get to whatever the obstruction or issue is, then work it back and forth as if you're working a tight rusted bolt. It's a finesse game. Hope this helps.

 

Holy cow that is a really nice car! Beautiful!

Rusty

 

Are you sure it's the engine that is stuck? My XJ6 occasionally would have the starter engage the flywheel but not turn... I'd have to turn the key off and back again to get it spinning. Maybe a starter or a connection issue?

If you really suspect the engine, I would recommend first removing the spark plugs as mentioned above, and purchase an inspection camera from Harbor Frieght for about $60. It has a flexible extension with a camera on the end and a full color 3" screen. Stick it down inside each plug hole and inspect the cylinders one by one. I had a car with a stuck engine, and doing this revealed a cylinder destroyed by a rodent that camped out in the intake manifold with droppings and urine slowly filling the cylinder with the open intake valve only to rust it solid!

Mildly stuck rings can be loosened up with Marvel Mystery oil, Diesel fuel, and/ or Seafoam. I have successfully restored compression in a car with very low compression on one cylinder with just soaking MMO, then using sea foam and turning the engine by hand with the plugs in to force it past the rings. Worked!

Good luck, car is beautiful and needs to be saved.

 

I have an 82 xj6 that will just clunk really loud when trying to start. The lights on the dash dim as well. I have to take the key out and put it back in in order to even get it to clunk. Every once in a while it wont even clunk it will just spin freely (I'm assuming I'm hearing the starter motor spinning freely). The car is in great condition with 79000 miles. It has been sitting for about 13 years and the previous owner said it ran fine. I have already put atf and penetrating oil in each cylinder and have been letting it soak for a while. I have not tried manually cranking the engine without the spark plugs in and I tried replacing the starter with a used one from ebay but both the starters have done the same thing. I have checked the wires going from the starter relay to the starter and the ones going from the battery to the starter and they look ok but I just mean they aren't rusty or corroded. They do look very old so I'm not sure if that counts as being enough to cause a short somewhere. I'm wondering if there is anything I should do other than what I have already. I am going to replace the starter with a new one. I am going to keep trying to free the engine but this time take the spark plugs out. Is there anything else I should check? I'm still new to working on cars so I have a basic knowledge of how they work. I was thinking maybe a compression test would yield some clues but honestly dont know how to perform one. Although I just got a kit from harbor freight. I'm assuming I just screw into where the spark plug goes and then pump? What should the compression be at? And what would it mean if the compression where out of the parameters? Thanks in advance.

 

 

It was imported from somewhere as you can see in the picture. I've decoded the vin as well and that's why I say it's an 82 and also because that's what the title of the car says. It has a clock on the dash and no trip computer. BUT... on the same label that has the vin that when decoded says it's a 1982, says that it was manufactured in 1985. But then it would have the trip computer right? It has really confused me...

 

I forgot to say, that XJ-C is the most wonderful example I have seen.

if you need to rebuild the engine, just do it. The car looks like it is worth it.

 

This is most definitely NOT a 1982 model - it has the post 83 console arrangement (as well as other characteristics I mentioned). Clearly the VIN has been decoded erroneously (see below). European models had the trip computer as an option (cars for Canada and the US came "fully optioned" with no options available beyond - your only choice was the colour combination!). The German-market Sovereigns most often did not have the trip computer - they had the clock instead, as your photo shows.

The VIN: the 10th unit in the VIN is C. This decodes as 1982 model year ONLY for cars built for "Canada, USA and Korea" (this is from the official Jaguar/Daimler decoding, part number JMM 2499 3). For other markets it does not designate a model year - but the decoder does not say what this means for other markets. The 11th unit ("C") indicates that the car was built at Browns Lane, Coventry. The serial number is consistent with a 1985 build date, not 1982.
The VIN decodes this car as a Jaguar Sovereign, baseline trim, 4 door saloon, 4.2 litre engine, Automatic LHD.

 

Jaguar only made the xj coupe for from 1975 to 1977. That's not a European model because the speed dial in mile not km. Lot of people have changed the bumper on the cars because of the look. No way it was made in the 80s the last ones that was registered is probably 1978. I had one that I sold, to buy another one. All xjc vin numbers will start with J5 and end BW. Vin plates are not the original someone has just type it on paper.

 

Sorry I just saw the plate but the numbers are not to the car the plate look like it taken from another car. The numbers on the plate were issue a lot later on, then the xjc were made.