Looking at the picture it looks like the chain broke with the tensioner caught beneath it. I think you might have gotten lucky. I think I would scope #5 and reassemble it with an old tensioner, so you don't have to buy a new one, in case the damage is worse than you think. Then compression test it.

 

Good idea or I was thinking about a leak down test.

 

Even better

 

If you remove the exhaust cam you can crank it over and check compression without putting new chains etc on. Also, it looks pretty obvious if there is a bent valve- the lift bucket doesn't come up as far as the rest.

 

Thank you Mr. Snyder, you were right. I took the cam off and the first valve from the front of the engine didn't come all the way back up. So now I know I have a bent valve.
My options:
Remove head and replace valve
Take the head off the 99 xj8 with a spun rod and installed it on this engine.
Remove engine and replace it with engine from the wrecked 99XK8. I was going to use this engine in the 99 xj8 to get it back on the road.
Pictures below show the top of the tensioner under the cam sprocket and the stuck valve.

 

I would throw the replacement engine in and redo the heads on this one at your leisure.

 

I'm thinking a head swap from a seized engine would be a lot easier than a whole engine swap. That way you can still have a backup motor, or 1 for another car.

 

I appreciate dsnyder's opinion and yours too Rick L, but I think I will take the head off of this car and see if I can replace the valve. If the damage is too severe I'll get the head from the motor with the bad rod. I have some of the maintenance records for this car. The engine has been well maintained. The throttle body, water pump and other parts have been replace. The engine is cleaner inside than any other Jaguar I have seen. Since I plan on keeping this car I think this is the way I'll go. I'll order the parts I need and in the meantime finish up on the xj8 I'm working on. Thank you for all of your imputs.

 

Ill wager you will be replacing one valve and the seal and be back on the road. Consider lapping the valves or having them done since you have the head(s) off. I say heads, because since you are already taking off the cam covers etc might as well.

 

I believe your right. I'll lap them in. I used to do it all the time with my sons 1200cc Yamaha engines when he raced.

 

Sorry, I meant timing cover not cam covers.

 

If you remove the cams you can check if the valves all are the same height at the top of the spring. If one is low that might be an indicator that it is bent. It might be quicker just to swap out the motor since you already have one. The damaged one would be easier to work with non a stand. Good luck!

 

Almost done with xj8 with just 2 minor issues left. Got all of my parts in today and will start breaking the xk8 down tomorrow. I'll start a new thread to show my progress since the title of this one is no longer relevant.

 

I'm almost certain there was at least one valve piston interference. But since that was only done with the starter and not when running it may not be too bad. But you must pull the head on that side to see. It will require new valves to replace those that are bent and a complete cam chain update on both sides. This all can be done in the car and would be a lot easier than changing the engine. I wouldn't think the impact to the pistons would be very severe.

 

I'm hoping that the chain and tensioner that was jammed on the side of the head may have helped to reduce the force on the piston when it hit the valve. Working on it now and so far it looks like only one bent valve.

 

With a slow hit like you must have had one valve would be all. But with the head off you will know for sure. Actually you got a great deal. You would have had to do the timing chain system completely anyway. Only additional is the head pulling. When you are through you will have a great car at a very low investment.

I don't know why shops are not aware of the tensioner problems as much as that is talked about. Had they not tried to start it the damage would have been minor and was something that had to be updated anyway. Oh well!!