The car is a 1977 Jaguar XJS v12 5.3 liter preHE. Auto transmission coupe European version.
it had a fire last October. Since then it sat in a garage. In maybe January I remember I was able to crank it with the starter motor. I never took apart the engine.

The current problem. No crank. I can't even turn the crankshaft with a spanner. Not with the starter either. Now I am taking out the spark plugs. After taking out 6 still no go. Not even a tiny bit.

maybe it is rust? Could there be something else?

 

Does the starter try to turn the engine? Its either a mechanical or electrical problem, you haven't given us a lot of information. Is power getting to the starter? Is it trying to turn the engine and the engine feels seized? Or is no electricity getting to the starter? The way to fix it will depend on the answer.

 

The starter relay is not in the car. I touch a piece of wire near the firewall to another piece of wire near the firewall. In January, this trick made it turn over with the starter motor. Now, there is a spark and a loud click but no movement. I removed the radiator to be able to access the crankshaft with a spanner. I put the spanner on it and I cannot turn it. When I am facing the front of the car with my butt toward the direction of travel, I try to turn the crankshaft clockwise with the spanner. It doesn't move.

 

So I think it is a mechanical problem, if it were electrical then the spanner thing would work I guess. I am removing now the spark plugs 1 bt 1 and using wd40 into the combustion chambers. Hope it will help me turn it. At least a tiny bit. So far after 8 plugs, no movement.

 

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I could always apply more force. It might break. How much force is still okay, I wonder.

 

There should be no need for excessive force; but a socket with a longer lever would be a better way to try it, there is not much leverage on that spanner.

 

I am with Greg here.

I use a socket and 18" breaker bar, no more force should be required.

If you want to soak the bores I would not use WD40. It evaporates too quickly.

I use a brew of ATF and Diesel Fuel at a ratio of 50/50. Pour some in, remembering the cylinders are on an angle, so a decent egg cup in each cylinder. Go away, try again in a weeks time.

BUT

You may have a jammed starter motor in mesh with the ring gear, common to some extent. The starter is not easy to get at, and one bolt is from the trans side, but I feel loosening it and wobbling it around will "unmesh" (good Aussie English there), if in fact it is jammed. I have had a few do that, especially when they do not start to "throw" the pinion away from the ring gear. I know the pinion is spring loaded to do that, but sitting so long I reckon the pinion may be rusted to the shaft, and stuck in the meshed position.

DO NOT rotate that engine Anti Clockwise PLEASE, but you know that dont you?????

That brew has never failed me yet, but time is the key, and beer of course.

 

You might say I am slow hehe. I just mixed 1 liter of diesel fuel with 1 liter of atf, poured about half of it into the engine through the spark plug holes. Before that I checked if it was still stuck(I tried small quantity of wd40 earlier), it was still stuck. My friend tells me that if were due to the starter being stuck then there should be a tiny bit of play in it because of the gears between the starter and the gear on the crankshaft. I didn't notice any movement at all. So I did this mix. If that doesn't fix it then the cylinder heads will have to come off I guess.

thanks for you replies, it keeps my soul happy, what would I think if no one cared huhh. Hehehe. So thanks. Hehehe.

I am too scared to climb under this when bit is on the axle stands. Huhh. I didn't check the conditionbof the starter. It does give a loud click when I try to operate it electrically.