Wonderful wonderful wonderful BobRoy.... Thank you! I look forward to receiving them!

 

You will find the training guide here https://www.mediafire.com/?aqxyzo1glqltd

 

Jay, you pics finally loaded. You are going to need to replace the piston. It looks like there is severe damage to the piston at the bottom of the pic. It looks like it might cause loss of compression but I think it will definitely bind the rings. You might decide if it might be more worthwhile to repair this engine or find a replacement. If the valve seat dropping was due to overheating, more than likely, I would replace the motor. If it overheated you might loose seats in the other head in the future or you might have other damage.

 

The piston on the left looks a bit beat up also.

 

Hi....

Thanks for the guide. I opened it and will download the file when home... When opening the link it seemed to offer 3 large files. Is their a specific location for setting and adjusting clearances?

I will go back and look at both cylinders caps/heads. The car was running and actually running pretty well on 7cyl for some time. Rich running and overheating CATS damage of course a concern.. I have another complete engine with 37k that I will switch to in the Spring,,,, I think. If I can get away with spending $3-400.00 on a new CH, put in some free love, attention and time - I will take my chances.

Yes, the head is a little roughed up. I want to know what you think the physical appearance of the head will do to compression. On both that appear rough for that matter. About 5 days ago I tested compression at 151 on the neighboring cylinder and no lower than 142lbs on any of them.

So,,, please dont scare me. What should I understand about the appearance of the cylinders and total catastrophic failure??? Im not a rich man and am doing what I can.

Changing the engine will not happen. What do you think?

 

I think if an engine change is not an option at this point, just put a good cylinder head on
and see what happens.
The file that you want is the engine repair course PDF, it's a large file but has a lot of information.

 

Jay, don't mean to scare you but giving you my opinion. It looks like the pieces of the valve seat that was in the cylinder got between the head and the piston when the piston was at top. The piston looks like it has some deep crevasses. It looks like the piece was there for quite a while and I'm sure it bent the edge of the piston that the upper compression ring is in a bind. I think that will proably be a loss of compression. How much who knows.
It just came to me. Fill that cylinder with water. If the water drains around the piston it is definitely done. If the water doesn't drain away you might take a chance.

 

That's a great point BobRoy and it made me think of something.

When the head was partly off, in process of coming off a good amount of left over water from draining the head did fall into the depressed 8th cyl. The cylinder in question.

Top to bottom nearly the cylinder was full until I cranked the crank pulley bolt, literally, to clear the water from the cylinders that had water due to coolant falling in in process of removing head. Now that I think about it, and it say for a while, a noticeable amount didn't mean down... Its not definitive,,, but it's a good sign. We shall see.

If I have to replace the engine I will but I am fairly confident this will work until I do swap engines in the Spring, or later, if things go right. Again, we shall see.

 

Put water in a corresponding cylinder to use as a base. If the water drains faster out of the damaged cylinder it will have a lower compression. The faster it drains the lower the compression.

 

What is the significance of using water rather than something like ATF or diesel?

Apologies for butting in - Just trying to better understand the 'debugging' process.

Thanks,
Mike

 

Water is cheaper and readily available. And as he said he already had water in the cylinder and is already in the crankcase. He of course will be changing oil and filter before start up. After his test he should drain the cylinders and wipe them dry. But you can use diesel or ATF if you want.

 

Understood.
I was wondering if there was some particular attribute of water that helped the diagnosis, given it's not engine internals friendly.

Doh! Occam's razor. Thanks BobRoy.


Jay, apologies for butting in. I've been following this thread with fingers crossed for you. Back to being a fly on the wall.

Good luck,
Mike

 

@Norri! Thank you so much for the training guide.... I just read the V8 section and so so many lingering questions were answered (I think, lol). I have more of course. If you have more training guides I'd be eternally grateful if you were willing to share them. Whatever you think is practical and would make sense for me right now...

So, an update. I've ordered the cylinder head and expect it to arrive this coming week. The head has no camshafts (the only thing not included) but the cams from the previous head are in good shape. I will reuse. I'll also figure out how to get to tolerances and clearances. If I cannot get to tolerances I will hold off until I can order new shims to adjust clearances. If there is anything anyone cna think of that I should know or understand - I would appreciate it.

I also think I know how to get to the KPS/CrankPS to set for timing. I ordered a cheap set with positioning/locking tools, spacers, wedges and such for the job. I hope its not a get what you pay for lesson.

Q: about the damaged piston. I've been thinking about what y'all said and after reading the training guide, getting a better understanding of the anatomy of an AJ-V8 engine, Im wondering how difficult it would be to change out a piston with structural sump and bed plate etc. in the way? I mean, from underneath, is it possible to get to, loosen a cap/rod and push a piston up and out of the block and replace piston and rings since the head is off now? If so, I've heard (and think I just read some things that went WAY over my head) that its not a simple as just replacing a/the bearing, new rod & cap due to wear and tear & the "shape", of the crankshaft main. That doing that, you run the risk of turning a bearing due to misshapen crank main... The car has 170K. Apologies for the mis and sloppy-language. This is new stuff for me.


Q: In setting timing. When I go to fully "retard" timing at time of re-setting, is that accomplished by turning the timing chain tensioning tool counter clockwise on the exhaust cam sprocket as I tighten it to 110-130Nm? If so, is that also to do with holding tension while I tighten intake sprocket to 110-130Nm? Will VVT and timing be set at that point? When I removed timing gear and sprockets I noticed play in the intake sprocket/bolt/camshaft and VVT apparatus and have been wondering, at time of re-setting timing and re-tightening,,,, HOW to reset VVT and get that "play" back appropriately.

THANKS for that DAMN guide Norri! Its sooo helpful.

Soon Ill send some pictures that SHOW what uncontrolled impatience, anger and frustration at a harmonic dampner/crank pulley can do to a timing chain cover, smh... Yup - its like that, lol...

Hoping ALL are well this fine Autumn Saturday Morning...

 

This is the guide for setting the timing:
How to replace timing chains on Jaguar XK 8 4.0 R V8 32V 1998-2002
The VVT sprocket has a spring to return it to the retarded position so when you reassemble everything all you are doing is removing the slack from the system and ensuring that the VVT remains retarded. The VVT sprocket shouldn't have any play as such, if it has then there is an issue with it, broken spring maybe?
As for the harmonic balancer pulley, use a puller to the point of almost breaking it then remove. It should have pulled forward by 1-2mm or so, give it a smack back onto the crank with a soft faced hammer. If you are lucky the cone will ping off and the pulley should be loose. If not, put the puller back on and re-tension, then remove. Then get a blow lamp and apply heat carefully to the hub taking care not to apply too much heat to surface next to the rubber coupling. Again you should hear a ping as the collet lets go and the pulley should be loose. Thats how i did it and I was so close at one point, to cutting it off with a grinder. Stupid idea if you ask me, whats wrong with a key drive!!!!!

 

Jay, there is no way of getting to the rod bolts without removing the sump. To remove the sump you will have to remove the engine or if you check my thread I gave you a link to earlier to see how I did it. But also bear in mind that I have a two post lift for the car and an engine hoist to lift the engine. I had to lift the engine as high as I could the built my brace to hold the engine up and the from underneath lower the subframe to get the sump out.
I know how much work this is and with the cost of all of the gaskets, piston, and head is why I suggested for you to just get another engine. I have the luxury of having 3 parts cars to get my head and piston from saving me money. I also have a spare engine I could put in the car but decided at the time to fix the one in the car. If I had to do it all over again I would have changed engines and repaired the other out of the car. It would have been so much easier.
The clearances that we're talking about is not the valve clearances but the camshaft to its journals clearances. These are critical for the life of the engine.

 

So BobRoy... I just went back and looked thru THIS string and I found your link in post #20 to "reparing 2000xk8... I reread the link... It was actually one of the threads I read thru, almost to completion, before buying my xk8. Its what gave me confidence to buy the car. There seemed to be support out there. Wondering, is there another "procedure" that you are referring to? One that is specific for camshafts, buckets, shims, clearances and tolerances etc,, - in addition to ALL of that great info in the "repairing 2000 xk8" thread? Just wondering. I think I will be able to use it going forward. I will little or no have no idea how to deal with the cam and journal clearances or the shim, lobe, valve clearances when the new head gets here on Tuesday.

I won't be replacing the piston, rod, bearingz or or or... I'm going to play that bottom half stuff by ear. At least wait for spring/summer...

@NBCat (if youre still there) thankfully the guides and tensioners are of the metal type and look almost new. I will snap some pictures of those, as well as my SHATTERRED timing chain cover (lol, yes I did) on my next day off. You warned me. I lost my isht for a second with the pulley... Involved a 3lb hammer and a ball joint pry bar... Im in the market for a new one BUT I was also thinking I might be able to patch it up - no laughing...

@phanc60844 Thanks for the info about VVT's... I guess what I was trying to explain and failed at was noticing that "spring" back when I was removing the timing chain, camshafts and loosening the (super tight) cam bolts. I noticed there was about 40 to 45 degrees they were able to move on the cam bolt axis. So, you're saying that that "spring" feel at rest is the VVT in the most retarded position,,, already? Thats a good thing then... Thanks for the link, Im going to dig into that reading now.. I got the pulley off some days ago btw - but (altho warned) broke something...

Still trucking.

 

Hello All.

Quick update. After much anticipation, the new/used cylinder head came in the mail yesterday. I was wondering what I'd be looking at out of the box. It looks to be in good condition BUT you cant judge a book by its cover.

With assembly lube - camshafts from the old CHead fell right into channels and move freely, nicely. Buckets/Tappets move freely in there cylinders. I don't think I'll be testing clearances and tolerances (camshaft to channels) unless someone here tells me that it's absolutely imperative. What do folks think about that and/or what should I be looking for understanding that? I simply don't have machine shop money - just my truth.

CHead came with caps, buckets and tappets... I intend to go in with feeler gage tonight to test the cam tappet clearances...

Question: Do people think I should use as much of the old stuff as possible??? Camshafts (of course), Caps, Buckets/Tappets??? Although there was the dropped seat in cylinder 8 in the old head, yes, and it ran super rich,,, the engine otherwise didn't tap, knock, clack, ting and and - at all... Was actually smooth sounding mechanically but rough idling and sluggish due to ZERO compression and misfire.

So - tell me how much a fool I am, lol...

I intend to begin installing the CHead on Saturday 11/5...

 

The only thing I would use from the old head is the cams. Use the buckets and cam caps that came with the new head. Oil the buckets and cams because they won't have and oil at first start up until it is pumped up from the crankcase. Don't forget to change oil before start up.

And no you are not a fool. You are trying to repair you car with the resources you have. The fools are the ones that don't use this forum.

Best of luck.

 

Hello BobRoy...

This is what I get! Last night after getting home from work I checked clearances with (original cams) old caps and old buckets (loose-est), then with new caps and old buckets (loose-r), then old caps and new buckets (spot on), then with new caps and new buckets (tight). How it turned out was old caps and new buckets measure out spot on.

I am amazed and impressed by the sweetness of engineering and machining in these components! I'm no expert (not even close) but I can feel the care and craftsmanship in these parts.... I'm amazed that something manufactured 14+ years ago can come together like this.

Im using assembly lube, will oil before cranking and will crank initially without fuel pump relays in before starting and YES, I will change oil and filter.

Thanks soooooo much!

 

Hello All...

Quickly...

I do have a question about thread locker? Understanding what I need to do in order to reinstall a cylinder head,,,, what bolts do you all consider a must for thread locker OR for anti-seize - if any???

Are any a no-no?