Tonight drove my 2001 XK8 to the store she ran perfect,when I came out I attempted to start the car, at first the Jag turned over slow, then it sort of started but making a grinding horrible noise like the engine was blown! I shut it of and walked home.I have no clue what is wrong but sounds god awful! How could the car go from running perfect then turned of to being totally messed up when restarting? this is freaking me out!

 

A few things need clarifying first and foremost.

1) Where in the world is the car in question, darkest Africa, Australia, or maybe USA, mmmmm. Different markets have different issues.

2) Have the top timing chain tensioners been changed in the life of the car????.

3) When was the last time the trans fluid was changed/serviced?????.

Might sound silly, coz you are annoyed at the moment, but all 3 are relevant to some sort of sensible answers.

ALSO, I suggest reposting this in the XK8 area, unless there is a Moderator lurking around who will oblige, which will target the guys that really know what is happening.

 

+1 to Grant, also mileage helps.......
It is probably the timing chain has slipped due to tensioner failure.
Cars with an engine made before August 13, 2001 have plastic tensioners.
To quote Tom (testpoint) The engine assembly date is the only way, short of pulling a valve cover to verify the status. Plastic or metal has no direct link to the VIN number. The engine serial number has the date encoded in it. The above date would produce a serial number of 010813xxxx. Your engine serial number can be obtained from a dealer using the VIN.
Do not try to turn the engine over until you've checked the tensioners (there are dozens of threads on the subject). It may not be wrecked yet.

 

Because of the way model years are given in the North American market, the cutoff on original plastic tensioners is closer to the 2002 model year given the August 13, 2001 cutoff date.

 

My automobile is located in Marina Del Ray,CA.
The transmission fluid was serviced 6 months ago.
The timing chain is original as far as I know.I have owned since 2009 the vehicle is a 2001 with 100,000 miles hit last week.

 

That, I'm afraid, is the sort of mileage by which the tensioners have normally failed.
You will need to look at the flats on the cams if the chain isn't obviously broken.
Search for secondary tensioners to get more info and good luck.

 

`I just read a post from another jag forum.The guy reported the same symptoms with his XK8 as mine.He had the car towed to a shop.The diagnosis came back as Flooded. I am not sure what that means, however it has been raining down here for the past three days.Is anyone familiar with this Flooded condition or what causes it, better yet how is the Flooded problem resolved?











?

 

I'm sure he was speaking of "fuel flooded", not "water flooded". If it's been sitting long enough, it's probably worked itself out. If it was an airplane, I could tell you how to clear the flooding (a very common problem), I'm not sure of the simplest way to do it with an automobile, but I'm sure someone here will have the answer. "Flooding" is usually fairly obvious, as you can normally smell the excessive, non-burned fuel.

 

Ignore the flooding possibility until you have had the valve covers removed and inspected the tensioners. Do not attempt to start the car until this has been done. The risk is too great.

 

To reiterate what Steve said above, it sounds like the timing chain has slipped as a result of a failed secondary tensioner. It is extremely important that you not try to start the car until you have the timing chain checked. If the timing chain has slipped, the engine may be destroyed, however, there is a chance the engine is ok but if you try to start it again, you will likely destroy it.

Mark

 

Is it possible to destroy the engine without getting the engine fully started? After I heard the noise, I turned the car of immediately.I did not attempt to drive it however I did try starting again after about five min,The engine turned over but would not start.

 

Yes, if the chain jumped two teeth instead of one, or if the chain is broken, major damage may have occurred.

 

The following post will give you an idea what is going on with the tensioners. I did mine as shown at 40K miles and the secondary tensioners as shown were already starting to crack. That many miles on your car I would bet you have a tensioner failure. If not change them anyway right away. Part of the noise you probably heard was piston valve interference I'm afraid. Just don't shoot the messenger.


https://www.jaguarforums.com/forum/x...ics-how-52653/

 

My apologies if this is too basic. The more common reason it is possible is because the engine is turning when you crank it which means the pistons are going up and down. If the timing chain jumped two teeth that has proven to be enough to throw the timing off to the point where the valves open (ie: get pushed down into the cylinders to allow fuel in) at a time when the piston is coming up (instead of at the right time when the piston is descending). If the chain broke the valves would pretty much be stationary against moving pistons. Either way,the piston hits the valve and the piston can be ruined and the valve bent. A bent valve alone might not be complete disaster but piston damage has been the end for most of these engines from what I have read (although I believe "bluexk8" is driving around with a slight "ding" on one of his pistons).

None of this is to say this actually happened to your engine; just wanted to explain why it is possible. Removal of the valve covers will tell you (or your mechanic) a lot. I hope its the lesser of all the possible evils here!

 

Dear Vettinrnd,
This exact scenario happened to me about 2 months ago. I drove around all morning, no problem, stopped the car, came out an hour later and heard a blood curdling sound before I even got the key turned all the way in the ignition. I shut down the ignition immediately and knew exactly what had happened based upon reading about the tensioners' problems on this forum. My mistake was that I had assumed that the tensioners had been replaced by the previous owner, and I didn't verify. Of course, when we pulled the covers, the tensioners and the timing chain on the driver's side were broken, however, miraculously, the engine was not damaged. I bought the full kit from Christopher's, lower and upper tensioners, chains, shortened bolts, gaskets...and had them installed at my local mechanic. Replaced the water pump at the same time. Kit was about $700, installation with water pump about $800. I also live in Los Angeles, and if you need a shop to do it, I can send you the guy who did mine and who works on all of my cars (in Northridge). Hopefully, you'll be as lucky as I was and not have to do an entire engine replacement.

 

I would like to thank all you guys for the helpful input.I had mechanic look at the jag this am. He ran a compression test resulting in good compression on the first 4 cylinders on drivers side On the passenger side 150 0 150 and 0.His diagnosis was head needs replacement.Being the novice that I am with engine repair, I would like to hear what your thoughts might be.

 

You undoubtedly have two bent exhaust valves which need replacing. The head and pistons MAY be damaged, but that will not be clear until the head is removed. Don't let him sell on the head replacement without proving it's necessary.

 

you told him you feared the timing chain jumped....so he did a compression test??? not a CLT test? uhm...am i the only one who would be taking it to a different mechanic?

 

If you have the $$4, I'd get a flatbed and take it to Hornberg Jag in Santa Monica. I've been using them for 10 years and am happy with except for the $$$.

 

I think the novice is the dipstick mechanic